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Thirty-six years ago this week, production unit No. 5,000 of the incomparable USAF/McDonnell F-4 Phantom II fighter-bomber was delivered in a public ceremony held at Lambert-St. Louis International Airport. This occasion (Wednesday, 24 May 1978) also marked the 20th anniversary of the type’s maiden flight (Saturday, 24 May 1958). Rhino, Lead Sled, Flying Brick, Flying Anvil, Old Smokey, Double Ugly, The Hammer; such are among the many terms of endearment used by pilots, back seaters and crew chiefs to describe the fabled F-4 Phantom II. Perhaps no other military aircraft is as emblematic of the air warfare mission than this classic two-seater, twin-jet airframe. Initially developed for the United States Navy, the Phantom was also employed by the U.S. Marine Corps, United States Air Force, and the air forces of many allied nations. As such, it served in numerous air warfare roles including fighter, bomber, attack, interceptor, defense suppression, and aerial reconnaissance. Indeed, over 50 variants of the F-4 were produced between 1958 and 1981. The aircraft was Mach 2.2-capable with a service ceiling of 60,000 feet. At a GTOW of 41,500 lbs, the Phantom could carry an ordnance load of 18,650 lbs wherein combinations of air-to-air missiles, air-to-ground missiles and a variety of multiple-yield bombs were employed. The Phantom was conceived in a time when reliance on missiles appeared to obviate the need for cannon in air combat engagegments. Subsequent air warfare experience in Viet Nam dictated otherwise and a centerline-mounted M61 Vulcan cannon was installed on the F-4E variant. The Phantom was heavily used by the military services in southeast asia and proved to be extremely effective. So much so, that it gained an additional nickname as the “World’s Leading Distributor of MiG Parts”. In its time, the Phantom also held many speed, altitude, and time-to-climb aircraft performance records. Noteworthy is the fact that the F-4 also holds the distinction of being the only aircraft flown by both the United States Air Force Thunderbirds and United States Navy Blue Angels flight demonstration teams. Today, there are over 600 Phantoms still flying worldwide. In the United States, one is likely to see a Phantom in its natural element only at an air show. Even in an age when the F-15 Eagle, B-1B Lancer and F-22 Raptor grace the sky, it is a choice experience indeed to witness the mighty F-4 come by show center in full afterburner. Rhinos forever!
Forty-nine years ago today, the USAF/Northrop X-21A Laminar Flow Control (LFC) experimental aircraft exhibited a significant reduction in skin friction drag. This achievement marked the first time in aviation history that the LFC principle was successfully demonstrated in flight. Perhaps aviation’s greatest holy grail is the pursuit of technology that allows a laminar boundary layer to be maintianed over the entire surface of an aircraft. Doing so holds the promise of significantly reducing the overall drag and thereby markedly increasing aircraft range and endurance performance. Maintaining a laminar boundary layer is difficult since the boundary layer is naturally turbulent over most of the aircraft at flight Reynolds numbers. The X-21A LFC system was based on the principle of boundary layer removal. This was achieved by drawing surface airflow through a series of fine, porous slots machined into the upper and lower surfaces of the wing. Airflow suction was provided by laminar flow control pumps located in nacelles on the underside of the wing. A pair of existing USAF B-66D Destroyer airframes were converted to the X-21A LFC configuration. Following conversion and checkout, Ship No. 1 (S/N 55-0408) first flew on Thursday, 18 April 1963 with Northrop test pilot Jack Wells doing the honors. On this initial test hop, the X-21A flew from Northrop’s Hawthorne Airport facility to Edwards Air Force Base, California. The first successful flight demonstration of aircraft drag reduction occurred on Tuesday, 14 May 1963. Ultimately, the X-21A demonstrated laminar flow control on about 75% of the type’s wing surface. Aircraft handling was satisfactory even with asymmetric boundary layer state on opposing wings (i.e., one wing with laminar flow and the other with turbulent flow). However, the Achilles Heel of LFC is the natural flight environment itself wherein dust, dirt, particulates and even bugs clog the boundary layer suction slots. LFC system maintenance is a nightmare; laborious, time-consuming and expensive. While clearly successful, the X-21A LFC Program came to an end in 1964. Despite its promise and allure, no operational production aircraft has ever utilized an LFC system.
Fifty-nine years ago this month, the USAF/North American YF-100A Super Sabre air-superiority fighter made its maiden flight with North American test pilot George S. Welch at the controls. During this initial test flight, the Super Sabre exceeded the speed of sound. The North American F-100 Super Sabre was the successor to the fabled F-86 Sabre fighter. The Super Sabre holds the distinction of being the first of the 1950’s era Century Series aircraft. It was also the first USAF production aircraft capable of flying supersonically in level flight. A total of 2,294 copies of the Super Sabre in 18 variants were produced over an operational lifetime that spanned 25 years. The air forces of the United States, France, Denmark, Turkey and the Republic of China (Taiwan) flew the aircraft affectionately known as “The Hun” by its pilots. The YF-100A was the initial version of the F-100. Two copies were produced. Ship No. 1 (S/N 52-5754) first flew on Monday, 25 May 1953 at Edwards Air Force Base, California. The aircraft performed well and hit Mach 1.03 on this first flight. The Super Sabre entered the USAF active inventory in late 1954 and set a number of speed records early in its operational life. The type won the Bendix Trophy for flying 2,020 nm at an average speed of 610.726 mph in September of 1955. The F-100 was also the first USAF combat jet to enter the Vietnam War. The USAF Thunderbirds flew the Super Sabre from 1956 to 1968. In spite of these notable achievements and distinctions, the aircraft was plagued by numerous design deficiencies and shortcomings that had to be corrected before the type reached an acceptable level of maturity. Particularly vexing were roll inertial coupling issues at high speeds and pitch-up tendencies at low speeds. Indeed, the aircraft had a deserved reputation as a widow-maker starting early in its career. History records that 889 F-100 airframes were destroyed in mishaps of one kind or another. That translates to a stunningly-high loss rate of 38.75%. Soberingly, 324 pilots lost their lives flying The Hun. Progress in aviation sometimes comes at a very high price. The F-100 Super Sabre, unique in its day, now a relic of history, is a particularly profound example of this truism.
Forty-years ago this month, the United States successfully conducted the next-to-last Apollo lunar landing mission with the flight of Apollo 16. The lunar landing occurred in the densely-cratered Descartes Highlands region located near the Descartes crater. On Sunday, 16 April 1972, Commander John W. Young, Command Module Pilot Thomas K. Mattingly II, and Lunar Module Pilot Charles M. Duke, Jr. lifted-off from Cape Canaveral’s LC-39A at 17:54:00 UTC. Apollo 16’s goal was to land in the lunar highlands whose surface material was older than that of the previously-visited lunar maria landing sites. Apollo 16 entered lunar orbit in the 75th hour of the outbound flight. Young and Duke undocked their Lunar Module Orion from the Command Module Casper piloted by Mattingly just short of 96.5 hours into the mission. Slightly more than 8 hours later, Orion safely touched-down near Descartes crater at 2:23:35 UTC on Friday, 21 April 1972. During their 71-hour lunar stay, Young and Duke conducted a trio of surface EVA’s to explore the Descartes region. Totaling more than 20 hours, these exploratory jaunts were facilitated by use of the motorized Lunar Rover that allowed the crew to venture as far as 2.7 miles from the Lunar Module. Although too extensive to adequately report here, the astronauts’ exploratory discoveries were truly phenomenal and ultimately changed our understanding of the Moon’s geology. Young and Duke collected roughly 211 lbs of lunar surface samples. At 1:25:47 UTC on Monday, 24 April 1972, Orion and her crew lifted-off from the lunar surface and docked with Casper a little more than 2 hours later. Following transfer of crew and cargo to Casper, Orion was jettisoned, and the 3-man crew remained almost in lunar orbit for almost a full earth day conducting experiments and surface observations before being rocketed out of lunar orbit. The trip home and earth atmospheric entry were uneventful in the main. Command Module splashdown took place at 19:45:05 UTC on Thursday, 27 April 1972 in the South Pacific Ocean. Crew, lunar cargo and spacecraft were safely recovered aboard the USS Ticonderoga some 37 minutes later. Apollo 16 was a grand achievement both scientifically and technologically. Along with the other Apollo lunar landing missions, Apollo 16 reminds us what be accomplished when vision, commitment and hard work are brought to bear. Today, the lone Apollo 16 spacecraft component to return to Earth, the Command Module Casper, is on public display at the U.S. Space and Rocket Center in Huntsville, Alabama.
Forty-five years ago this month, the United States Air Force successfully flew and recovered the third and final Project PRIME Flight Test Vehicle (FTV-3). PRIME stood for Precision Recovery Including Maneuvering Entry. The ability to generate aerodynamic lift allows a reentry vehicle to maneuver along the endoatmospheric portion of its entry flight path. The main goal of Project PRIME was to flight test a hypersonic, maneuvering lifting body vehicle designated as the USAF/Martin SV-5D. Configured with 3-axis aerodynamic and reaction controls, the SV-5D weighed 892 lb and measured 6.7 ft, 4.0 ft and 2.8 ft in length, span and height, respectively. Thermal protection was provided by a then-novel charring ablator material. The SV-5D was an autonomous vehicle and thus had its own guidance, navigation and control system. On Wednesday, 19 April 1967, PRIME FTV-3 was launched by an Atlas booster from Vandenberg Air Force Base, California. The vehicle’s trajectory took it toward Kwajalein Missile Range (KMR) located 4,400 nm to the west in the Marshall Islands. FTV-3 performed a variety of controlled maneuvers during entry in which a maximum crossrange of 710 nm was achieved. The vehicle modulated crossrange by banking as much as 64 degrees while simultaneously pulling angles-of-attack as high as 57 degrees to achieve the required lift vector. Indeed, this very same crossrange maneuvering strategy would be used by the Space Shuttle Orbiter a decade and a half later. FTV-3 deployed a drogue parachute as it passed through Mach 2 at 100,000 feet. Main parachute deployment then occurred in the vicinity of 50,000 feet. As the vehicle-parachute combination neared an altitude of 12,000 feet, the crew of a USAF/Lockheed JC-130B Hercules then executed the only successful aerial recovery of a PRIME flight test vehicle. A planned fourth flight was cancelled due to the great success achieved in the preceding trio of PRIME flight tests. As a final note, FTV-3 was subsequently returned to the contractor for post-flight inspection and testing. Today, the recovered FTV-3 airframe is on public display at the United States Air Force Museum in Dayton, Ohio.
Fifty-years ago this week, future Apollo 11 Astronaut Neil A. Armstrong piloted the fifty-first and longest mission of the X-15 Program. The research flight was highlighted by Armstrong having to make a 180-degree turn over Los Angeles to recover the X-15 back at Edwards Air Force Base following a 45-mile overshoot of the intended landing area. X-15 Ship No. 3 (S/N 56-6672) was configured with the Honeywell MH-96 adaptive flight controller for the purpose of easing the pilot’s workload during atmospheric exit and entry. NASA test pilot Neil Armstrong was assigned responsibility to perform the early flight testing of this unit. On Friday, 20 April 1962, Armstrong made his fourth and last flight in Ship No. 3. Peak altitude and speed achieved during the flight was 207,447 feet and 3,788 mph (Mach 5.31), respectively. As Armstrong approached the Edwards area from the northeast, his trajectory ballooned anomalously. That is, rather that continuing to descend and scrub-off velocity, the X-15 climbed slightly and maintained an above-nominal speed. As he passed by Rogers Dry Lake heading south, Armstrong was still traveling at 100,000 feet and Mach 3. Armstrong banked the aircraft until it was practically inverted and invoked full elevator in an effort to get the X-15 to bite into the atmosphere and turn back towards Edwards AFB. However, it wasn’t until he was over Los Angeles, roughly 45 miles beyond the base, that he got the aircraft turned around. Now, would he have enough energy to glide back and touchdown on Rogers Dry Lake? Somehow, Armstrong managed his energy state properly and made it back to Edwards. But it was a close thing. Rather than making the standard overhead turn and landing on the north side of Rogers Dry Lake, Armstrong executed a straight-in approach and landed on the south side of the desert playa. Chase pilots are recorded to have said that he cleared the Joshua trees at the south end of Rogers Dry Lake by only about 100-150 feet. Nonetheless, pilot and aircraft were unscathed in what turned-out to be the longest flight in the history of the X-15 Program (12 minutes 28.7 seconds). In the post-flight joviality, fellow NASA test pilots reportedly referred to Armstrong’s adventure as “Neil’s cross-country flight”.
Sixty-years ago this week, the USAF/Boeing YB-52 Stratofortress (S/N 49-231) all-jet strategic bomber took to the air on its maiden flight. The crew for this historic event consisted of Boeing’s Alvin M. “Tex” Johnston (command pilot) and USAF Lt Col Guy M. Townsend (co-pilot). The B-52 was designed by the Boeing Company for the United States Air Force in the 1940’s. Its mission was to provide the Strategic Air Command (SAC) with a global nuclear strike capability. As originally designed, the B-52 featured a top speed of 513 mph at 35,000 feet and a range of 6,005 nm for a gross take-off weight of 280,000 lbs. Power was provided by an octet of Pratt and Whitney J-57 turbojets; each of which generated a maximum sea level thrust of about 10,000 lbs. With a fuselage length of 160 feet, the B-52 was configured with a huge wing having a span of 185 feet and a leading edge sweep of 35 degrees. The initial pair of prototype B-52 aircraft (S/N 49-230 and S/N 49-231)received the designation of XB-52. However, the second XB-52 (S/N 49-231) was subsequently designated as the YB-52 and was the first B-52 airframe to fly. It did so on Tuesday, 15 April 1952. This 2.35-hour maiden flight originated from Boeing Field near Seattle, Washington and recovered at Larson AFB, Washington. The big airplane performed well on its initial foray into the wild blue yonder and it was clear from the start that USAF and Boeing had a winner. Indeed, the Stratofortress would go on to a storied career whose length and breadth could not have been foreseen by its creators. The type’s speed, range and gross weight would increase over the years. New and more powerful engines would provide the improved performance. A total of 744 copies of the B-52 were built in eight (8) different production versions (B-52A through B-52H); roughly 90 of which are still flying. Amazingly, three (3) generations of Air Force pilots have flown the aircraft. With a service period that began in the Cold War and extends into the present, the B-52 Stratofortress holds the distinction of being the longest serving bomber aircraft in the history of military aviation.
Forty-seven years ago this week, the first International Telecommunications Satellite (Intelsat I) was launched into a geosynchronous orbit by a Thrust-Augmented Delta (TAD) launch vehicle. Popularly known as Early Bird, the satellite holds the distinction of being history’s first commercial communications orbital platform. It was also the first satellite to provide direct and quasi-instantaneous communication between the North American and European continents including transmission of television, telephone, and telefax signals. Fired into orbit from LC-17A at Cape Canaveral, Florida on Tuesday, 06 April 1965, Early Bird consisted of a 28-inch diameter cylinder measuring 23-inches in height. Spin-stabilized about its longitudinal axis, the satellite weighed just 85 lbs. Power was provided by an array of 6,000 solar cells covering its external surface. Early Bird was capable of handling 240 two-way telephone circuits or a single TV channel via a pair of 6-watt transmitters. Though primitive by today’s standards, Early Bird functioned well its role as a communications satellite. Among its many accomplishments, the satellite helped make possible the first live television broadcast of the splashdown of a manned spacecraft when Gemini 6 returned to earth in December of 1965. Early Bird was deactivated in January of 1969 following a 48-month service period that began on Monday, 28 June 1965. This service duration was well beyond the type’s original design life of 18 months. When the Atlantic Intelsat satellite failed at a most inopportune moment, Early Bird was returned to operational status on Sunday, 29 June 1969 to support the Apollo 11 mission. This reactivation period was brief and ended on Wednesday, 13 August 1969. With the exception of a short period of reactivation in 1990 to honor its 25th launch anniversary, Early Bird has silently orbited the Earth ever since. The Intelsat Program grew remarkably following the fledging flight of Early Bird so long ago. Indeed, more than 120 Intelsat and Intelsat-derivative satellites have been orbited by a variety of American, Russian, French and Chinese launch vehicles since 1965.
Forty-nine years ago this week, the United States successfully conducted the fourth Saturn I test flight designated as Saturn-Apollo No. 4 (SA-4). Launched from LC-34 at Cape Canaveral, Florida on Thursday, 28 March 1963, SA-4 reached an apogee of 70 nm, attained a maximum speed of 3,670 mph and flew 216 nm downrange during the brief 15 minute suborbital mission. The Saturn I measured 180 feet in length, featured a maximum diameter of 21.4 feet and weighed 1,123,600 l bs at lift-off. The first stage propulsion system consisted of an octet of H-1 engines generating a total sea level thrust of 1,600,000 lbs. Nominal burn time was 150 seconds. Part of the early Apollo Program, SA-4 was the last flight to fire just the first stage rocket engines. As with the previous three launches, the primary goal of SA-4 was to validate the structural integrity of the Saturn I vehicle. However, a significant additional objective of SA-4 was to verify the GNC system’s ability to properly handle an engine-out anomaly during first stage operation. As such, one of the H-1 engines was programmed to intentionally shutdown at approximately T+100 seconds. The GNC system did indeed respond properly to this anomaly by rerouting propellants to the remaining seven (7) engines which burned longer to compensate for the loss of thrust. SA-4 also employed a nonfunctional second stage which incorporated the external shape of the ultimate second stage design. This included the presence of vent ducts, fairings, simulated camera pods and various externally-mounted antennae. SA-4 also fired a retrorocket system that would be employed to aid separation of various rocket stages on later flights. Despite dire warnings in some quarters, the shutdown H-1 engine remained intact despite the build-up of heat caused by the lack of cooling propellant flowing around the nozzle. This survivability feature underscored the robustness of the clustered engine concept employed in the Saturn series of space boosters. Interestingly, the engine-out compensation capability demonstrated on SA-4 was in fact successfully employed during a pair of later Apollo missions; Apollo 6 and Apollo 13.
Fifty-years ago this week, a supersonic flight test of the B-58A Hustler’s crew escape system was successfully conducted with a black bear named Yogi as the test subject. Ejection took place with the test aircraft maintaining a speed of 850 mph at 35,000 feet. The USAF/Convair B-58A Hustler was the world’s first operational supersonic strategic bomber. With a GTOW of 176,000 lbs and powered by a quartet of General Electric J79-GE-5A turbojets, the aircraft featured a maximum speed of Mach 2 at 40,000 feet. The Hustler air crew consisted of a pilot, bombardier/navigator and defensive systems officer seated in separate, tandem flight stations. When the Hustler entered the operational inventory in 1960, standard ejection seats were used for air crew emergency egress. However, the chances of surviving a supersonic ejection in the B-58A or any other aircraft were quite low due to severe wind blast and exposure effects. The resolution of this issue came in the form of an encapsulation system that protected the crew member during ejection, deceleration, parachute deployment and landing. Upon activation, clamshell doors would close and seal the crew member in the escape capsule. The entire assembly was then fired out the top of the aircraft and into the air stream. Flight testing of this system was initially performed using bears due to the similarity of their internal organ arrangement with that of a man’s. On Wednesday, 21 March 1962, a 2-year old female black bear named Yogi served as the first live test subject. The tranquilized bear survived the ride upstairs, the ejection event, 7.5 minute parachute descent and landing with no apparent ill effect. Subsequent testing with other bears helped prove the escape system’s airworthiness. Although many sources claim that this was the first supersonic ejection of a live creature, such is not the case. That particular distinction (if it can be called that) goes to North American Aviation pilot George F. Smith who bailed out of his stricken F-100 Super Sabre at 777 mph on Sunday, 26 February 1955. Although battered and terribly injured in the process, Smith survived and lived to fly another day.
Forty-one years ago this month, the first long-tank thrust-augmented Delta rocket with six Castor-2 strap-on boosters was launched from LC-17A at Cape Canaveral, Florida. Known as Delta M-6, the thrust-augmented launch vehicle was capable of placing 1,000 lbs in geosynchronous transfer orbit (GTO) or about 2,850 lbs in low earth orbit (LEO). Three of the solid strap-on boosters were ignited on the pad along with the MB-3-3 first stage liquid rocket motor which generated 195,000 lbs of vacuum thrust. Each solid rocket strap-on produced 58,000 lbs of vacuum thrust and burned for 37 seconds. At T+38 seconds, the remaining three strap-ons were air-ignited just as the ground-ignited motors were burning out. All of the Castor-2 solid rockets separated from the launch vehicle shortly after burnout of the trio of air-ignited motors. The ground-ignited boosters went first, followed 5 seconds later by the air-ignited set. The primary payload for the Delta M-6 mission was the Explorer 43 satellite which was inserted into a highly-elliptical orbit on Saturday, 13 March 1971. Orbital parameters included an apogee of 122,146 statute miles a perigee of 146 statute miles and an orbit inclination of 28.75 degees. Outfitted with a dozen specialized instruments, Explorer 43 obtained detailed scientific measurements of solar ray, cosmic ray, electrical field and energetic particle activity in space. These data allowed scientists to study the cislunar environmnt during a period of decreasing solar flare activity. Explorer 43 performed well right up to the day it reentered the Earth’s atmosphere on Thursday, 02 October 1974.
Forty-three years ago this month, the Apollo Lunar Module (LM) flew in space for the first time during the Apollo 9 earth-orbital mission. This technological achievement was critical to the success of the first lunar landing mission which occurred a little over 4 months later. The Apollo Lunar Module (LM) was the world’s first true spacecraft in that it was designed to operate in vacuum conditions only. It was the third and final element of the Apollo spacecraft; the first two elements being the Command Module (CM) and the Service Module (LM). The LM had its own propulsion, life-support and GNC systems. The vehicle weighed about 32,000 lbs on Earth and was used to transport a pair of astronauts from lunar orbit to the lunar surface and back into lunar orbit. The spacecraft was really a two-stage vehicle; a descent stage and an ascent stage weighing 22,000 lbs and 10,000 lbs on Earth, respectively. The descent stage rocket motor was throttable and produced a maximum thrust of 10,000 lbs while the ascent stage rocket motor was rated at 3,500 lbs of thrust. On Monday, 03 March 1969, Apollo 9 was rocketed into earth-orbit by the mighty Saturn V launch vehicle. The primary purpose of this mission was to put the first LM through its paces preparatory to the first lunar landing attempt. During the 10-day mission, the crew of Commander James A. McDivitt, CM Pilot David R. Scott and LM Pilot Russell L. “Rusty” Schweickart fully verified all moon landing-specific operational aspects (short of an actual landing) of the LM. Key activities included multiple-firings of both rocket motors and several rendezvous and docking exercises in which the LM flew as far as 113 miles from the CM/SM pair. By the time the crew splashed-down in the Atlantic Ocean on Thursday, 13 March 1969, America had a new operational spacecraft and a fighting chance to land men on the moon and safely return them to Earth by the end of the decade.
Fifty-two years ago this week, the Strategic Air Command (SAC) fired its first USAF/North American AGM-28 Hound Dog cruise missile. A USAF/Boeing B-52G Stratofortress from the 4135th Strategic Wing at Eglin AFB, Florida served as the air-launch platform. The AGM-28 Hound Dog was a turbojet-powered cruise missile designed to penetate enemy air space and deliver a 1 megaton-yield thermonuclear warhead. The vehicle measured 42.5 feet in length, 2.33 feet in diameter and had a wing span of 12 feet. Launch weight was 10,140 lbs. The type’s non-afterburning Pratt and Whitney J52-6 turbojet was rated at 7,500 lbs of sea level thrust and could propel it to a maximum speed of about 1,430 mph (Mach 2.1). Interestingly, the AGM-28’s turbojets were run at full power, making the B-52 carrier bomber a 10 engine aircraft. Following take-off, the Hound Dog’s engines were shutdown and its fuel tanks topped-off. The Hound Dog’s flight envelope was such that it could cruise anywhere between tree-top level and 55,000 feet. Two vehicles were externally-carried by the B-52 launch aircraft; one each from the right and left wing pylon stations. Maximum post-launch flyout range was about 617 nm. North American Aviation began development of the missile in 1957 and the first powered flight occurred in April of 1959. A series of flight tests ensued that proved the missile’s various systems including radar, guidance, navigation and control. These developmental activities culminated with the first SAC shot on Monday, 29 February 1960 and establishment of an Initial Operating Capability (IOC) shortly thereafter. A total of 772 Hound Dog airframes were built and served in the SAC inventory through 1976. The Hound Dog served well as a deterent to nuclear confrontation between the United States and the Soviet Union; no Hound Dog was ever fired in anger.
Forty-seven years ago today, NASA’s Ranger 8 spacecraft successfully completed a mission to obtain high-resolution photographs of the lunar surface. The flight was the penultimate mission in the Ranger Program, the goal of which was to help scientists better understand the topography of potential Apollo lunar landing sites. Ranger 8’s mission began with launch from LC-12 at Cape Canaveral, Florida on Wednesday, 17 February 1965. The Atlas-Agena B launch vehicle placed Ranger 8 along a direct hyperbolic trajectory that would allow the spacecraft to intercept the Moon nearly 65 hours later. The mission aim point was situated in the Mare Tranquilitatis region of the lunar surface. All of the action would take place in the final 23 minutes of flight as a complement of six (6) vidicon cameras snapped photos all the way to impact. A pair of the cameras featured a full scan capability; one wide-angle, one narrow-angle. The remaining four (4) cameras were partial scan systems; two wide-angle, two narrow-angle. Ranger 8 arrived at the Moon on Saturday, 20 February 1965. The first of 7,137 high-resolution photos was taken at an altitude of 1,388 nm above the lunar surface. The last photo, featuring a resolution of about 5 feet, was imaged when the Ranger 8 spacecraft was only 525 feet above the surface; a mere 0.09 seconds before a 6,000-mph impact with the Moon. Impact occurred only 10 nm from the mission aim point. This was exceptional accuracy considering the trip from Earth was over 205,000 nm. While Ranger 8’s mission was brief and its end violent, the photographic bounty transmitted back to Earth helped make possible America’s first manned lunar landing on Sunday, 20 July 1969. The landing site? None other than Mare Tranquilitatis.
Fifty-three years ago this week, the U.S. Navy’s first production Martin P6M-2 SeaMaster flyingboat took-off from Chesapeake Bay on its maiden flight. Martin chief test pilot George A. Rodney was at the controls of the 4-man, swept-wing naval bomber as it took to the skies on Tuesday, 17 February 1959. Featuring a fuselage length of 134 feet, wingspan of 102 feet, and a wing leading edge sweep of 40 degrees, the P6M-2 had a GTOW of about 175,000 lbs. Armament included an ordnance load of 30,000 lbs and twin 20 mm, tail-mounted cannon. Power was provided by a quartet of Pratt and Whitney J75-P-2 turbojets; each delivering a maximum sea level thrust of 17,500 lbs. The SeaMaster’s demonstrated top speed at sea level was in excess of Mach 0.90. This on-the-deck performance is comparable to that of the USAF/Rockwell B-1B Lancer and USAF/Northrup B-2 Spirit and exceeds that of the USAF/Boeing B-52 Stratofortress. P6M pilots reported that the aircraft handled well below 5,000 feet when flying at Mach numbers between 0.95 and 0.99. While designed for low altitude bombing and mine-laying, the aircraft was flown as high as 52,000 feet. As a result, the Navy even considered the SeaMaster as a nuclear weapons platform. Despite the type’s impressive performance and capabilities, the SeaMaster Program was cancelled in August of 1959. Budgetary issues and the emerging Fleet Ballistic Missile System (Polaris-Poseidon-Trident) led to this decision. Loss of the P6M SeaMaster Program was devastating to the Glenn L. Martin Company and resulted in this notable aerospace business never again producing another aircraft.
Fifty-years ago this week, the NASA TIROS IV meteorological satellite was successfully orbited by a United States Air Force Thor-Delta launch vehicle. Launch took place from LC-17A at Cape Canaveral, FL on Thursday, 08 February 1962. The TIROS (Television Infra Red Observation Satellite) Program marked the first use of satellite technology to provide near-continuous photographic coverage of global cloud formations from space. Historically, TIROS photos were instrumental in helping mature the science/art of global weather forecasting. The TIROS IV mission was designed to maintain an operational TIROS in orbit for an extended period and to obtain improved photographic data to be used in weather forecasting during the northern hemisphere hurricane season. The cylindrical spacecraft measured 42 inches in diameter and 19 inches in height. Constructed of aluminum and stainless steel, TIROS IV weighed 285 lbs. A bank of 63 onboard batteries was charged via an array of 9,260 solar cells that covered the vehicle’s external surface. The satellite carried an upgraded lens system to improve the clarity of photos taken by its twin cameras. As a result, TIROS IV photos were the best to date in the TIROS Program. An international facsimile transmission network was also instituted that allowed the US Weather Service to share photos with weather services worldwide. From its nearly circular orbit of 420 nm above the surface of the Earth, TIROS IV snapped over 32,000 photos over the course of its 161-day mission.
Forty-eight years ago this month, USAF Major Robert A. Rushworth flew the 100th flight test of the X-15 Program. Piloting his 18th mission in the manned hypersonic aircraft, Rushworth achieved a maximum speed of 3,618 mph (Mach 5.34 ) in X-15 Ship No. 1 (S/N 56-6670). The date was Tuesday, 28 January 1964. Peak altitude attained during the 8 minute and 17 second flight was 107,402 feet. Using a trio of aircraft, the X-15 Program would go on to register 199 official research missions between June of 1959 and October of 1968. Bob Rushworth flew 34 of those missions; more than any of the twelve men who piloted the famed black rocket-plane. Bob Rushworth had many notable experiences while at the controls of the X-15 including one episode where the nose gear deployed above Mach 4.2 and another where a main landing skid deployed above Mach 4.4! Each time he was able to get the airplane back on the ground in one piece. On a more positive note, Bob Rushworth flew the X-15 as fast as 4,018 mph (Mach 6.06) and as high as 285,000 feet. For this latter achievement, Rushworth was awarded Astronaut Wings by the United States Air Force.
Forty-five years ago this week (Friday, 27 January 1967), the Apollo 1 prime crew perished as fire swept through their Apollo Block I Command Module (CM) during a ground test at Cape Canaveral, Florida. The crew of Command Pilot Vigil I. “Gus” Grissom, Senior Pilot Edward H. White II and Pilot Roger B. Chaffee had been scheduled to make the first manned flight of the Apollo Program some three weeks hence. Shortly after the fire started at 23:31:04 UTC (6:31:04 pm EST), “We’ve got a fire in the cockpit” was reported across the communication network by Astronaut Chaffee. Believed to have started just below Grissom’s seat, the fire quickly erupted into an inferno that claimed the men’s lives within 30 seconds. While each received extensive 3rd degree burns, death was attributed to toxic smoke inhalation. The post-mishap investigation uncovered numerous defects in CM design, manufacturing and workmanship. The use of a (1) pure oxygen atmosphere pressurized to 16.7 psia and (2) complex 3-component hatch design (that took a minimum of 90 seconds to open) sealed the astronauts’ fate. A haunting irony of the tragedy is that America lost her first astronaut crew, not in the sideral heavens, but in a spacecraft that was firmly rooted to the ground.
Twenty-one years ago this week (Thursday, 17 January 1991), USAF/Lockheed F-117A Nighthawk aircraft were employed against more than 31 percent of Iraqi targets during the initial 24 hours of Operation Desert Storm. This high utilization rate came despite the fact that the Nighthawk comprised a mere 2.5 percent of all Coalition aircraft used in the Persian Gulf War air campaign. The Black Jet’s unique stealth characteristics allowed it to attack high-value military targets with impunity in the Baghdad area despite the city’s heavy SAM and AAA defenses. Moreover, the use of precision-guided weapons provided for target elimination while minimizing collateral damage and civilian casualties. By the end of hostilities, F-117A forces had flown 1,300 missions and dropped in excess of 2,000 tons of ordnance. Roughly 1,600 targets were struck at a success rate of 80 percent. No Nighthawk aircraft or pilot was lost in the conflict. The F-117A’s phenomenal success during Operation Desert Storm led her air and ground crews to coin this bold motto; “We own the night.”
Forty-one years ago this week (Tuesday, 12 January 1971), the USAF/Boeing Short Range Attack Missile (SRAM) was ordered into production. Known as the AGM-69, the nuclear-armed weapon was designed for both internal and external carriage by the USAF/Boeing B-52 Stratofortress. SRAM would eventually see service with the F-111A Aardvark and the B-1B Lancer as well. Featuring a maximum range of 110 nm, the Mach 3-capable missile was able to deliver its W69 variable-yield nuclear warhead with a CEP of 1,400 feet. The SRAM external airframe was completely covered with 3/4-inch of rubberized material to reduce its radar cross-section (RCS). Additional RCS reduction was achieved through the use of phenolic tail control surfaces. Approximately 1,500 SRAM’s were manufactured before the missile’s production cycle was halted in August of 1975.
Forty-seven years ago this week, the USAF/General Dynamics F-111A Aardvark tactical strike aircraft successfully swept its variable-geometry wings for the first time in flight. Company test pilots Dick Johnson and Val Prahl flew this test on what was the second flight of Ship No 1. (S/N 63-9766). Flying out of Carswell Air Force Base in Fort Worth, Texas, the aircraft’s wings were swept through the full range of wing sweep (16 to 72.5-deg) without incident. This important milestone in the development of the all-weather, supersonic-capable, low-level penetration F-111A took place on Wednesday, 06 January 1965.
Twenty-five years ago this month, the storied Rutan Model 76 Voyager aircraft successfully completed history’s first non-stop, non-refueled flight around the world. The crew of Dick Rutan and Jeana Yeager departed Edwards Air Force on Sunday, 14 December 1986 and returned 216 hours, 3 minutes and 44 seconds later on Tuesday, 23 December 1986. The FAI-official distance covered during the flight was 21,707.6 nm. For their efforts, the flight crew, Burt Rutan (designer), and Bruce Evans (builder and crew chief) received the 1986 Collier Trophy.
Fifty-seven years ago today, the No. 1 USAF/Convair YF-102A (S/N 53-1787) aircraft flew for the first time on a flight that originated from Lindbergh Field near San Diego, California. A redesigned variant of the USAF/Convair YF-102, the delta wing aircraft incorporated a new drag-reducing design feature known as Whitecomb’s Area Rule. Applied for the first time on the YF-102A airframe, this innovative design technique proved to be entirely successful. Whereas the YF-102 could not go supersonic in level flight, the YF-102A was able easily exceed Mach 1 in a climb and cruise at Mach 1.2.
Fifty-three years ago this month, the USAF/RCA Project SCORE spacecraft became the world’s first communications satellite. Within 24 hours of being orbited by an Atlas B intercontinental ballistic missile (ICBM), the SCORE (Signal Communications Orbit Relay Equipment) payload broadcast a Christmas message to the world recorded by U. S. President Dwight D. Eisenhower. The president’s message was the first time a human voice was heard from space.
Sixty-four years ago this month, the USAF/Boeing XB-47 Stratojet took to the air for the first time. The legendary Stratojet would go on to become the first all-turbojet strategic bomber to enter operational service with the United States Air Force.
Fifty-seven years ago this month, the USAF/Boeing B-29 Superfortress strategic bomber was officially retired from the active inventory of the United States Air Force. The famed World War II-era aircraft had a service life of less than a dozen years.
Fifty-six years ago this month, the USAF/Bell X-2 Starbuster experimental flight research aircraft made its initial powered flight from Edwards Air Force Base, California. Legendary test pilot USAF Lt. Col. Frank K. “Pete” Everest was at the controls of the rocket-powered, swept-wing X-aircraft.
Fifty-four years ago this month, the first ablative nose cone to survive entry into the Earth’s atmosphere was formally presented to the American public. President Dwight D. Eisenhower displayed the recovered nose cone during a national television broadcast from the Oval Office.
An object making a hypersonic entry into the the Earth’s atmosphere from space possesses a great deal of kinetic energy. This energy of motion is transformed to thermal energy as aerodynamic drag slows the vehicle during atmospheric flight. A portion of the entry thermal energy is absorbed by the vehicle structure in a process referred to as aerodynamic heating. This heat transfer process causes the temperature of the external surface of the vehicle to significantly increase.
From a vehicle survivability standpoint, three parameters are key; (1) maximum heat transfer rate, (2) maximum surface temperature and (3) total thermal energy absorbed by the vehicle during entry. The concern is that there is enough kinetic energy in the entry flight domain to vaporize any known material if that energy is completely absorbed by the vehicle.
One has only to look into the heavens at night to become convinced of the ferocity of the entry environment. The streaks of white, yellow, green, blue, or red light that dramatically flash into and out of existence are associated with the vaporization of meteors transiting the atmosphere. Few meteors have enough original mass to allow a minor portion thereof to reach the ground. Those that do are referred to as meteorites.
The problem of surviving atmospheric entry was a major research topic in the 1950’s. Attention focused on protecting the nuclear warhead carried by the reentry vehicle of an Intercontinental Ballistic Missile (ICBM). A pair of research scientists at the NACA Ames Research Center in California, H. Julian Allen and Alfred J. Eggers, are credited with solving the problem. The key was to hemispherically-blunt or round the nose of a reentry vehicle.
A blunted forebody disposes a detached, hyperbolic-shaped shock wave which slows the post-shock flow to subsonic speeds in the stagnation region. A byproduct of this flow deceleration is a significant increase in post-shock static pressure and temperature. While this dramatically increases vehicle wave drag, most of the high temperature air passes around the vehicle and thus never physically comes in contact with it. The result is that only a small fraction of the overall thermal energy of the freestream flow is convected to the vehicle surface.
In contrast to the above, a sharp-nosed vehicle nose disposes an attached, highly-swept shock wave. This flow topology results in a large fraction of the overall thermal energy being convected to the vehicle surface. The is because the degree of post-shock flow slowing in such a situation is small. Indeed, the post-shock flow has a high supersonic Mach number. Now, due to the “no-slip” condition caused by fluid viscosity, the flow velocity at the vehicle surface is zero. Thus, the bulk of the flow deceleration has to occur within the boundary layer. The huge shearing stresses and temperature gradients that result generate extreme heat flux rates at the vehicle surface.
On Thursday, 08 August 1957, a Jupiter-C launch vehicle carrying a one-third scale version of a Jupiter IRBM nose was launched from LC-6 at Cape Canaveral, Florida. The nose cone traveled 1,168 nautical miles, reaching nearly 9,000 mph and an altitude of 260 nautical miles in the process. During reentry an ablative heat shield was used to protect the nose cone from the aerodynamic heating environment. The vehicle parachuted into the Atlantic Ocean and was recovered by Navy swimmers within three hours of launch.
On Thursday, 07 November 1957, President Dwight D. Eisenhower displayed the recovered Jupiter IRBM scaled nose cone in a nationally televised broadcast from the Oval Office. The excellent condition of the recovered vehicle was a stark testament to the effectiveness of a blunted, ablative nose cone to weather the rigors of reentry heating. This historic breakthrough would forever change the science of atmospheric entry. Indeed, it would ultimately make possible successful entry of Apollo astronauts returning from the Moon at 25,000 mph.
Today, one can view the recovered Jupiter IRBM subscale nose cone at the Smithsonian’s National Air and Space Museum in Washington, DC. Specifically, it is on public display in the Space Race Exhibition at the National Mall Building.
Forty-four years ago this month, the No. 3 USAF/North American X-15 research aircraft broke-up during a steep dive from an apogee of 266,000 feet. The pilot, USAF Major Michael J. Adams, died when his aircraft was torn apart by aerodynamic forces as it passed through 65,000 feet at more than 2,500 mph.
The hypersonic X-15 was arguably the most productive X-Plane of all time. Between 1959 and 1968, a trio of X-15 aircraft were flown by a dozen pilots for a total of 199 official flight research missions. Along the way, the fabled X-15 established manned aircraft records for speed (4,534 mph; Mach 6.72) and altitude (354,200 feet).
The X-15 was a rocket, aircraft and spacecraft all rolled into one. Burning anhydrous ammonia and liquid oxygen, its XLR-99 rocket engine generated 57,000 lbs of sea level thrust. Reaction controls were required for flight in vacuum. Each flight also required careful management of aircraft energy state to ensure a successful, one attempt only, unpowered landing.
On Wednesday, 15 November 1967, the No. 3 X-15 (S/N 56-6672) made the 191st flight of the X-15 Program. In the cockpit was USAF Major Michael J. Adams making his 7th flight in the X-15. He had been flying the aircraft since October of 1966. Like all X-15 pilots, he was a skilled, accomplished test pilot used to dealing with the demands and high risk of flight research work.
X-15 Ship No. 3 was launched from its B-52B (S/N 52-0008) mothership over Nevada’s Delamar Dry Lake at 18:30 UTC. As the X-15 fell away from the launch aircraft at Mach 0.82 and 45,000 feet, Adams fired the XLR-99 and started uphill along a trajectory that was supposed to top-out around 250,000 feet. If all went well, Adams would land on Rogers Dry Lake at Edwards Air Force Base in California roughly 10 minutes later.
Around 85,000 on the way upstairs, Adams became distracted when an electrical disturbance from an onboard flight experiment adversely affected the X-15’s flight control system, flight computer and inertial reference system. As a result, data on several key cockpit displays became corrupted. Though with some difficulty, Adams pressed-on with the flight which peaked-out around 266,000 feet approximately three (3) minutes from launch.
As a result of degraded flight systems and perhaps disoriented by vertigo, Mike Adams soon discovered that his aircraft was veering from the intended heading. He indicated to the control room at Edwards that his steed was not controlling correctly. Passing through 230,000 feet, Adams cryptically radioed that he was in a Mach 5 spin. Mission control was stunned. There was nothing in the X-15 flight manual that even addressed such a possibility.
Incredibly, Mike Adams somehow managed to recover from his hypersonic spin as the X-15 passed through 118,000 feet. However, the aircraft was inverted and in a 45-degree dive at Mach 4.7. Still, Adams may very well have recovered from this precarious flight state but for the appearance of another flight system problem just as he recovered the X-15 from its horrific spin.
X-15 Ship No. 3 was configured with a Minneapolis-Honeywell adaptive flight control system (AFCS). Known as the MH-96, the AFCS was supposed to help the pilot control the X-15 during high performance flight. Unfortunately, the unit entered a limit-cycle oscillation just after spin recovery and failed to change gains as the dynamic pressure rapidly increased during Ship No. 3’s final descent. This anomaly saturated the X-15 flight control system and effectively overrode manual inputs from the pilot.
The limit-cycle oscillation drove the X-15’s pitch rate to intolerably-high values in the face of rapidly increasing dynamic pressure. Passing through 65,000 feet at better than 2,500 mph (Mach 3.9), Ship No. 3 came apart northeast of Johannesburg, California. The main wreckage impacted just northwest of Cuddeback Dry Lake. Mike Adams had made his final flight.
For his flight to 266,000 feet, USAF Major Michael J. Adams was posthumously awarded Astronaut Wings by the United States Air Force. His name was included on the roll of the Astronaut Memorial at Kennedy Space Center (KSC) in 1991. Finally, on Saturday, 08 May 2004, a small memorial was erected to the memory of Major Adams near his X-15 crash site situated roughly 39 miles northeast of Edwards Air Force Base.
Fifty-four years ago today, the USAF/Northrop SNARK intercontinental cruise missile successfully flew its maximum range mission of 5,000 statute miles for the first time. SNARK would go on to become the only strategic cruise missile ever operationally deployed by the United States.
The SM-62A SNARK was designed to deliver nuclear ordnance at strategic ranges. The vehicle was conceived as an autonomous, winged, turbojet-powered aircraft with a high subsonic cruise capability. Ground launch was provided by a pair of disposable, high-thrust rocket boosters. The SNARK’s origins date back to the middle 1940’s.
The missile’s name, SNARK, is not an acronym. Rather, SNARK has reference to the mythical creature highlighted in Lewis Carroll’s poem, “The Hunting of the Snark”. Jack Northrop, president of Northrop Aircraft Company, developer of the SNARK, is credited with selection of the missile’s name.
SNARK engineering development and flight testing took place between 1946 and 1960. This protracted gestation period was partially due to mission requirements drift on the part of the Air Force. However, challenging technical problems, a flat funding profile and mission relevancy issues also served to draw-out the development effort.
The original SNARK prototype was designated as the N-25 by Northrop. The missile was designed to fly 1,550 statute miles and cruise at Mach 0.85. N-25 flight testing occurred between December of 1950 and March of 1952. While the results were not particularly encouraging, USAF still wanted a strategic cruise missile. This led to the development of a larger, more capable airframe designated as the N-69.
The N-69 SNARK configuration measured 67.2 feet in length and featured a wing span of 42.25 feet. Launch weight was roughly 49,000 lbs. Power was provided by a single Pratt and Whitney J-57 turbojet that generated a sea level thrust of 10,500 lbs. The missile carried a single W39 nuclear warhead with a yield of 3.8 megatons. The SNARK was ground-launched using a pair of Aerojet General solid propellant rocket boosters that produced a combined thrust of 260,000 lbs. The complete launch stack weighed 60,000 lbs.
The design operational range for the N-69 airframe was 5,500 nm. The type had a top cruise speed and ceiling of 650 mph and 50,000 feet, respectively. Maximum mission time was on the order of 11 hours. Northrop was constrained to use a celestial navigation system to get the SNARK to its distant target. The company optimistically advertised a CEP of 8,000 feet.
On Thursday, 31 October 1957, a SNARK N-69E airframe (S/N N-3324) successfully flew a strategic range flight for the first time. Launch occurred from either LC-1 or LC-2 (the historical record is unclear here) at Cape Canaveral, Florida. The missile flew 5,000 statute miles to its target near Ascension Island in the South Atlantic Ocean.
While the range achieved on the SNARK’s Halloween 1957 flight test was impressive, guidance system accuracy was quite poor. Indeed, guidance system performance deficiencies plagued the SNARK Program throughout its life. Witness the fact that through May of 1959, the best the SNARK guidance system could do on long range flights was impact within 4.3 nm of the target. Moreover, the first guidance flight to be successfully completed did not occur until February of 1960.
The latter 1950’s saw rapid development of successful Intercontinetal Ballistic Missile (ICBM) systems within the United States and the Soviet Union. These suborbital warhead delivery systems outperformed the SNARK by every measure. In spite of its obvious obsolescence, low reliability and marginal accuracy, USAF opted to field the weapon anyway.
The first and only SNARK missile wing, consisting of 30 airframes, was operationally-deployed at Presque Isle AFB, Maine in February of 1961. However, the type’s deployment period would be brief. Newly-inaugurated President John F. Kennedy cancelled the SNARK Missile Program soon after taking office. As a result, the SNARK missile wing at Presque Isle AFB was deactivated in June of 1961.
America’s aerospace history is filled with unique aerospace systems that saw limited or no operational service. Notable examples include the Navaho, B-70, F-107, X-20 and the X-33. While these vehicles never filled the measure of their creation, the technology and capability accrued during their development greatly benefitted succeeding generations of aerospace craft. Such is the case for SNARK. Indeed, historically importnant operational missile systems such as Jupiter, Atlas, Minuteman and Titan were direct heirs of technology, capability and technical lessons-learned derived from the SNARK experience.
Fifty-nine years ago this month, the USN/Douglas XA3D-1 Skywarrior prototype strategic bomber made its initial test flight at Edwards Air Force Base, California. Legendary Douglas test pilot George R. Jansen was at the controls of the swept-wing, turbojet-powered, carrier-based aircraft.
The USN/Douglas A3D Skywarrior was the product of late 1940’s Navy studies calling for a carrier-based, long range bomber capable of delivering a 10,000 lb bomb load. Douglas Aircraft Company was awarded a contract to manufacture and test a pair of XA3D-1 airframes (BuAer No. 125412 and No. 125413) in 1949. Westinghouse was selected as the powerplant provider.
The XA3D-1 had a design weight of roughly 68,000 lbs, which would allow the aircraft to operate from existing Navy aircraft carriers. Power was provided by a pair of Westinghouse J40 turbojets. Each of these powerplants generated 7,500 lbs of military thrust and 10,500 lbs of afterburner at sea level. Unfortunately, the XA3D-1 was underpowered with these powerplants. In any event, the J40 engine experienced significant development problems and never did see production.
The No. 1 XA-3D-1 (BuAer 125412) made its maiden flight on Tuesday, 28 October 1952 with Douglas test pilot George R. Jansen doing the piloting honors. Although a Navy program, the flight was conducted at Edwards Air Force Base in California. The safety provided by the presence of the world’s longest (11.5 miles) natural runway, Rogers Dry Lake, was one reason for doing so. The XA3D-1 initial test hop was unremarkable.
The results of early Skywarrior testing significantly aided the evolutionary development and improvement of the aircraft. The A3D-1 was the first Skywarrior variant to see limited production. This was ultimately followed by the A3D-2; considered by many to be the definitive Skywarrior. Large for a carried-based aircraft, the Skywarrior was nick-named “The Whale”.
The A3D-2 measured 76.3 feet in length and had a wing span of 72.5 feet. Wing leading edge sweep and planform were 36-deg and 812 square feet, respectively. The aircraft had a GTOW of 82,000 lbs versus a empty weight of 39,400 lbs. Power was provided by twin Pratt and Whitney J57-P-10 turbojets. Each powerplant generated 10,500 lbs of military thrust at sea level. Each engine could produce an additional 2,400 lbs of thrust using water injection.
The A3D-2 could carry a maximum conventional or nuclear bomb load of 12,800 lbs. Maximum unrefueled range was 1,826 nm. With a service ceiling of 41,000 feet, the aircraft typically cruised at 452 knots. Maximum airspeed was 530 knots. The A3D-2 flight crew consisted of a pilot, navigator and bombardier. Interestingly, the crew was not provided with ejection seats as a cost-saving measure. This led Skywarrior crews to asert that “A3D” was actually an acronym that meant “All 3 Dead”.
While the Skywarrior was designed as a strategic bomber, the aircraft was used in other roles over the course of its long operational life. Indeed, the Skywarrior was modified to serve in the electronic warfare role, as a photo-recon platform and as an aerial tanker. Historical records indicate that 282 Skywarriors were produced between 1956 and 1961.
The Skywarrior and its crews served faithfully throughout the Cold War period including Vietnam. Significantly, the Skywarrior holds the distinction of being the largest and heaviest aircraft ever to see operational service aboard an aircraft carrier. The last operational Skywarriors were taken out of the active inventory in September of 1991.
As a further tribute to the Skywarrior, the Air Force liked the aircraft so much that it contracted with the Douglas Aircraft Company to design, test and produce a very similar aircraft; the B-66 Destroyer. First flight occurred in June of 1954. Operationally, the B-66 was used primarily in the electronic warfare and recon roles. A total of 294 airframes were ultimately produced for the junior service. Happily, ejection seats were standard equipment.
Thirty-seven years ago this month, the first USAF/Rockwell B-1A multi-role strategic bomber was rolled-out at the contractor’s USAF Plant 42 facility in Palmdale, California. The swing-wing, supersonic aircraft was intended to replace the venerable USAF/Boeing B-52 Stratofortress.
The USAF/Rockwell B-1A Lancer was the product of 1960’s-era Air Force studies calling for a supersonic-capable, low-level penetration bomber. North American Rockwell was awarded a contract to manufacture and test four (4) prototype airframes (S/N’s 74-0158, 74-0159, 74-0160 and 76-0174) in 1970. General Electric was selected as the powerplant provider.
The B-1A was designed for both Mach 2.3 flight at 50,000 feet and Mach 0.85 flight at sea level. The aircraft was able to satisfy these requirements by virtue of several design features. Formost among these was the aircraft’s ability to adjust its wing sweep in flight. Coupled with its sleek, aerodynamically-efficient fuselage, this gave the aircraft very low wave drag. Another key element were the type’s quartet of General Electric F-101 turbofan engines which generated a total of 120,000 lbs of afterburner thrust at sea level. Thrust performance was optimized through the use of variable-geometry air intakes.
The B-1A measured 150.2 feet in length and featured a wing span that could be varied in flight from 136.7 feet (15-deg sweep) to 78.2 feet (67.5-deg sweep). Gross take-off and empty weights were 395,000 lbs and 115,000 lbs, respectively. Unrefueld range was 5,300 nm. The aircraft was designed to carry 75,000 lbs of nuclear and/or conventional ordnance internally and up to 40,000 lbs externally. Operationally, the B-1A’s four-man crew would consist of aircraft commander, pilot, offensive systems officer and defensive systems officer.
The No. 1 B-1A (S/N 74-0158) was rolled out for the public on Saturday, 26 October 1974. About 10,000 people attended this event which took place at Rockwell’s facility on USAF Plant 42 property in Palmdale, California. The big, white, sleek aircraft was visually stunning and bore a majestic presence. The media covered the event in some detail.
The No. 1 B-1A took-off for the first time from USAF Plant 42 on Monday, 23 December 1974. The flight test aircrew included Charles Bock, Jr. (aircraft commander), Col. Emil (Ted) Sturmthal (pilot) and Richard Abrams (flight test engineer). The aircraft’s landing gear was not retracted and wing sweep was not varied during this initial flight test. These systems were operated on the type’s second flight test which occurred on Thursday, 23 January 1975.
Each of the B-1A prototypes served a distinct role in the aircraft’s flight test program. The No. 1 aircraft (74-0158) was the flying qualities evaluation testbed. It flew 79 times (405.3 hours) and was the first B-1A to hit Mach 1.5 (Oct 1975) as well as Mach 2 (Apr 1976). Aircraft No. 2 (S/N 74-0159) evaluated structural loading parameters, flew 60 times (282.5 hours), and achieved the highest Mach number of any B-1A aircraft (Mach 2.22 on Oct 1978). Aircraft No. 3 (S/N 74-0160) amassed 138 flights (829.4 hours) as an offensive and defensive systems testbed. Aircraft No. 4 (76-0174) had a similar role in that it tested essentially operational versions of the offensive and defensive systems. It flew 70 times (378 hours).
The B-1A program was cancelled by the Carter Administration in June of 1977. While it never attained operational status, the aircraft broke new ground in mutiple areas including aircraft design, aerodynamics, flight performance, and electronic warfare. Indeed, the multiple technological capabilities that it pioneered were ultimately exploited in the type’s direct heir; today’s USAF B-1B Lancer.
Fifty-six years ago this month, the USAF/Republic YF-105A Thunderchief took to the air for the first time from Edwards Air Force Base. With Republic test pilot Russell M. Roth at the controls, the fabled Thud exceeded the speed of sound during its maiden flight.
The USAF/Republic F-105 Thunderchief was a member of the fabled Century Series of jet-powered production aircraft. It was designed specifically as a fighter-bomber capable of delivering nuclear ordnance. Famed Republic aircraft designer Alexander Kartveli is credited with creation of the F-105 airframe.
The Thunderchief was a big airplane. The original version (YF-105A) measured 61.5 feet in length and featured a wing span of 35 feet. Gross take-off and empty weights were 40,561 lbs and 28,966 lbs, respectively. Power was provided by a single Pratt and Whitney J57-P-25 turbojet which produced 15,000 lbs in afterburner thrust at sea level.
The YF-105A was designed to have a maximum speed of 778 mph at sea level and a maximum speed at 36,000 feet of 857 mph. The aircraft had a combat ceiling of 49,950 feet and could carry an ordnance load of about 8,000 lbs. With an internal fuel load of 850 gallons, the aircraft could fly 878 nm. Range was increased to 2,364 nm with the addition of 1,870 gallons carried externally.
The first YF-105A Thunderchief (S/N 54-0098) made its maiden flight on Saturday, 22 October 1955. This initial test hop was conducted at Edwards Air Force Base, California, with Republic test pilot Russel M. Roth doing the piloting honors. Despite a high level of transonic drag resulting from the lack of fuselage area-ruling, the aircraft hit Mach 1.2 on its first time in the air.
The Thunderchief entered the USAF inventory in May of 1958 as the F-105B. A number of variants followed in the years that followed. The F-105D was the definitive single-seater version. The F-105F served as a combat-capable trainer. The F-105G was also a two-seater and flew the Wild Weasel mission.
Performance of the later versions of the Thunderchief significantly exceeded that of the YF-105A. For example, the F-105D Thunderchief was powered by a Pratt and Whitney J75-P-19W turbojet that produced 24,500 lbs of thrust in afterburner. The engine was fed by side-mounted, variable-geometry, forward-swept air intakes that were more efficient than the original design. Further, the fuselage employed area-ruling to reduce transonic wave drag. Taken together, these changes gave the Thunderchief a Mach 2+ capability.
The F-105D had a gross take-off weight of 52,546 lbs carrying a 14,000 lb conventional ordnance load-out. Empty weight was 27,500 lbs. The aircraft’s small wing area (385 square feet) resulted in a very high wing loading. While this permitted very stable flight during the high-speed, low-altitude run-in to the target, the Thunderchief was no match for the agile MIG-17 flown by the North Viet Nam Air Force. Notwithstanding, the Thunderchief had 27.5 air victories against the North Vietnamese compared to 17 losses to the enemy.
Republic Aircraft manufactured a total of 833 copies of the Thunderchief by the time production ended in 1964. Viet Nam was the Thunderchief’s war. Over 20,000 sorties were flown by Thunderchief aircrews. Many of these missions were flown into the Pack VI region of the air war over North Viet Nam. A total of 382 Thunderchief aircraft were lost during the air war. This inordinately-high loss rate was largely due to the shackling and politically-motivated rules of engagement enforced by the Johnson Administration.
The F-105 no longer graces the skies. However, one can see the aircraft on display at a number of air museums throughout the country. The National Museum of the United States Air Force at Wright-Patterson Air Force Base in Dayton, OH is one such example.
In its time, the Thunderchief was a mighty performer and particularly loved by its pilots. Many books have been written by those who flew “The Thud” into hostile skies. These personal accounts are quite inspiring and often poignant. To get a sense of what it was like to fly and fight in the Thunderchief, Jack Broughton’s “Thud Ridge” is an unforgettable read.
Fifty-two years ago this month, the USAF Bold Orion air-launched ballistic missile performed a successful intercept of the Explorer VI satellite. This event marked the first time in history that a endoatmospherically-launched missile intercepted a target vehicle in space.
Bold Orion was a 1950’s-era air-launched ballistic missile (ALBM) prototype developed by Martin Aircraft for the United States Air Force (USAF). It was part of USAF’s Weapons System 199 (WS-199) research and development program. The goal of WS-199 was to develop technology to be used in emerging strategic weapons systems by the Strategic Air Command (SAC).
The Bold Orion was developed using components obtained from existing missile systems as a cost savings measure. The missile was initially configured as a single stage vehicle. Power was provided by a Thiokol TX-20 Sergeant solid rocket motor. However, preliminary flight tests showed that the vehicle lacked sufficient kinematic performance. The addition of an ABL X-248 Altair solid rocket motor made Bold Orion a two-stage vehicle.
The two-stage Bold Orion configuration was 37 feet in length and had a maximum diameter of 31 inches. The vehicle was air-launched from a USAF/Boeing B-47 Stratojet aircraft. Missile launch occurred while the carrier aircraft executed a zoom climb maneuver. The option was available to fly either a maximum range endoatmospheric mission (about 1,000 nm) or achieve exoatmospheric altitudes as high as 150 nm.
The Bold Orion flight test program consisted of a dozen missions. The first six of these were single-stage vehicles which were flown between May and November of 1958. The remaining rounds were two-stage configurations which were tested between December of 1958 and October of 1959. All missions were air-launched off the coast of Florida and flown down the Eastern Test Range.
Bold Orion’s grandest moment came on the occasion of its final flight. The goal was to test the vehicle’s ability to perform in the anti-satellite (ASAT)role. The Explorer VI satellite served as the mission target. A direct hit was not required since an actual interceptor would be configured with a nuclear warhead. In that scenario, detonation of the warhead within several miles of the target would be sufficient to destroy it.
Bold Orion’s ASAT mission occurred on Tuesday, 13 October 1959. Launch took place within the Atlantic Missile Range Drop Zone (AMR DZ). The altitude, latitude and longitude of the drop point were 35,000 feet, 29 deg North and 79 deg West, respectively. Bold Orion successfully intercepted the Explorer 6 satellite, passing its target at a range of less than 3.5 nm and an altitude of 136 nm.
The Bold Orion ASAT test marked the first interception of a satellite in space and verified the feasibility of an ASAT system. However, negative political ramifications came along with technical success. Specifically, the Eisenhower Administration intended to keep space neutral. Bold Orion’s overtones of hostile intent did not play well with that mandate. As a result, ASAT development within the United States was halted not long after Bold Orion’s final mission.
Bold Orion’s success gave USAF the flight experience and technology to develop the Skybolt ALBM. Known as GAM-87, this two-stage missile sported a W59 thermonuclear warhead with a yield of 1.2 megatons. A quartet of pylon-mounted Skybolt missiles would be carried by and air-launched from a USAF/Boeing B-52H Stratofortress. While Skybolt’s kinematic performance was impressive, test problems and the development of the Submarine-Launched Ballistic Missile (SLBM) ultimately led to its cancellation.
Fifty-five years ago this month, the first Jupiter-C launch vehicle flew a suborbital mission in which it attained a maximum velocity of 16,000 mph. The successful flight test was a significant step in the development of what would ultimately result in the United States’ first satellite launcher.
The Jupiter-C was a derivative of the Army’s Redstone Short Range Ballistic Missile (SRBM). It was designed to test sub-scale models of the warhead reentry vehicle used by the Jupiter Intermediate Range Ballistic Missile (IRBM). The “C” in Jupiter-C stood for Composite Reentry Test Vehicle.
The Jupiter-C launch vehicle was composed of three (3) separate stages. The vehicle measured 68.5 feet in length and had a maximum diameter of 70 inches. Lift-off weight was 62,700 lbs. All Jupiter-C launches took place from LC-5 and LC-6 at Cape Canaveral, Florida.
The Jupiter-C first stage was a Redstone missile stretched by 8 feet to allow for increased propellant load capability. Power was provided by a single Rocketdyne A-7 liquid rocket engine that burned alcohol and liquid oxygen as propellants. The A-7 produced 78,000 lbs of thrust for about 150 seconds.
The Jupiter-C second and third stages consisted of clusters of Baby Sergeant solid rocket motors. Specifically, the second stage clustered eleven (11) of these motors that generated a total thrust of 16,500 lbs for 6 seconds. The third stage utilized a cluster of three (3) Baby Sergeants that produced a total thrust of 4,500 lbs for 6 seconds. Propellants for the solids included polysulfide-aluminum and ammonium perchlorate.
The second and third stage solid rocket motors were housed in a large cylinder that sat atop the first stage. This cylinder (referred to as the “tub”) was spun at a rotational velocity that varied from 450 to 750 RPM in flight. The purpose in doing so was to mitigate the effects of thrust misalignments and provide gyroscopic stability during the firing periods of the second and third stage solid rocket motor clusters.
The kinematic performance capability of the Jupiter-C was such that it could readily put a payload in orbit given a fourth stage. However, the State Department strictly forbade any attempt to orbit a satellite with the Jupiter-C. Even if that were to happen “accidentally”. The philosophy at the time was that America’s first satellite would be orbited using a non-military booster.
The first Jupiter-C was launched from LC-5 at Cape Caneveral, Florida on Wednesday, 19 September 1956. Launch time was 05:47 UTC. (For the record, we note here that some historical sources quote the launch date as being Thursday, 20 September 1956.) The vehicle did not carry a scaled Jupiter nose cone test article, but a dummy fourth stange and about 20 lbs of instruments in its stead.
The kinematic performance of the first Jupiter-C was impressive. The vehicle reached a speed of 16,000 mph (1,500 mph less than orbital requirement) at third stage burnout. Impact occurred in the Atlantic Ocean roughly 2,861 nm downrange of the launch site. Apogee for the suborbital flight was 593 nm.
There were only two more Jupiter-C test flights after the inaugural mission. These occurred on Wednesday, 15 May 1957 and Thursday, 08 August 1957, respectively. Each vehicle carried a scaled Jupiter nose cone test article. Surface temperatures exceeded 2,000 F and the ablative thermal protection system worked remarkably well. So much was learned from these missions that further Jupiter-C flights were deemed unnecessary.
The addition of a live fourth stage rocket motor to the Jupiter-C was known as Juno I. Indeed, using a single Baby Sergeant solid rocket motor and a small scientific payload constituted the Explorer I satellite. History records that Explorer I was orbited by a Juno I launch vehicle on Friday, 31 January 1958. Significantly, it was the first satellite to be orbited by the United States.
Sixty-three years ago this week, the USAF/Convair XF-92A Dart made its first official flight from Muroc Army Airfield in California. Convair test pilot Ellis D. “Sam” Shannon was at the controls of the experimental delta-winged aircraft.
The XF-92A Dart holds the distinction of being the first delta-winged, turbojet-powered aircraft in the United States. It was designed and produced by the Consolidated Vultee Aircraft (Convair) Company for the United States Army Air Force. Only one copy of the type (S/N 46-682) was ever built and tested.
At the time, the delta wing planform was something of a novelty. Convair designers chose this shape principally due to its aerodynamics benefits. For example, transonic wave drag is significantly lower than that of a swept wing of equal area. The delta wing also exhibits favorable lift-curve slope, center-of-pressure travel and ground effect characteristics.
The large chord of a delta-winged aircraft allows for static pitch stability to be realized without the use of a classic horizontal tail. Pitch control is obtained via wing trailing edge-mounted elevons; surfaces which combine the functions of an elevator and the ailerons. When differentially-deflected, elevons provide roll control.
The XF-92A measured 42.5 feet in length and had a wing span of 31.33 feet. Empty and gross weight were 9,978 lbs and 14,608 lbs, respectively. Early in its development, the XF-92A was powered by an Allison J33-A-21 turbojet which generated a maximum thrust of only 4,250 lbs. The final version of the aircraft was configured with an Allison J33-A-16 turbojet which produced a maximum sea level thrust of 8,400 lbs.
The XF-92A made its maiden flight on Saturday, 18 September 1948 from Muroc Army Airfield, California. Convair test pilot Ellis D. “Sam” Shannon did the piloting honors. Although the aircraft handled well, it was a bit over-responsive to control inputs. In addition, the XF-92A was underpowered.
Convair completed the last of 47 Phase I test flights on Friday, 26 August 1949. The Air Force conducted the first Phase II flight test on Thursday, 13 October 1949 with none other than Major Charles E. “Chuck” Yeager at the controls. Phase II testing was completed on Wednesday, 28 December 1949 by USAF Major Frank K. “Pete” Everest.
Following Phase II testing, the aircraft was re-engined with an Allison J33-A-29 turbojet capable of generating 7,500 lbs of sea level thrust. The Air Force continued to fly the XF-92A on various and infrequent test missions into February of 1953. Pilots of historical note who flew the aircraft include Al Boyd, Kit Murray, Jack Ridley, Joe Wolfe and Fred Ascani. It appears that the Air Force flew a total of 47 flight tests using the XF-92A.
The lone XF-92A was turned over to the National Advisory Committe For Aeronautics (NACA) once the Air Force was done testing it. The aircraft was promptly configured with an Allison J33-A-16 turbojet that generated 8,400 lbs of sea level thrust. NACA test pilot A. Scott Crossfield flew the XF-92A a total of 25 times. The type’s last flight occurred on Wednesday, 14 October 1953.
The XF-92A was not all that great from a piloting standpoint. Among other things, the aircraft had a severe pitch-up problem which produced normal accelerations between 6 and 8 g’s. The XF-92A was also plagued with landing gear failure problems. As noted previously, the aircraft was underpowered; a situation that was not uncommon for jet-powered aircraft of the era.
Inspite of its flaws, the design and flight experience gained from the XF-92A’s development led to an extensive series of delta-winged highly-successful aircraft produced by Convair in the 1950’s. These historically-significant aircraft include the F-102 Delta Dagger, F-106 Delta Dart, B-58 Hustler, XF2Y Sea Dart and XFY Pogo.
Sixty-years ago this month, a live biological payload consisting of a primate and a colony of mice was lofted to an altitude of 236,000 feet by a two-stage Aerobee X-8 sounding rocket. The mission marked the first recorded instance where a mamallian payload survived the rigors of high altitude rocket flight.
The post-World War II period saw a rapid expansion in America’s efforts to explore space. Emphasis was placed on flying faster and higher. Rocket power led the way. First, into the upper atmosphere, and ultimately into the lower reaches of space.
Early post-war flight research capitalized on using V-2 rockets captured from the defeated Third Reich. These vehicles were brought to America and adapted to boost instruments to high altitude. While servicable in this new role, the V-2 was less than ideal from the standpoints of launch, performance and payload recovery.
In light of the above, a variety of purpose-built rocket systems rapidly came into being during the post-war years. Prominent among these was the Aerobee high altitude sounding rocket. Aerojet General initiated development of the system in 1946. The first Aerobee test vehicle was flown in November of 1947 at White Sands proving Grounds (WSPG).
The first Aerobee configuration was about known as the X-8. It consisted of a solid propellant booster and a liquid sustainer. The booster generated 18,000 lbs of thrust for 2.5 seconds. Sustainer propellants included aniline and furfuryl-alcohol (fuel) and red fuming nitric acid (oxidizer). The sustainer rocket engine produced 2,600 lbs of thrust for 40 seconds.
The X-8 launch vehicle measured 26.4-feet in the length with a launch weight of about 1,100 lbs (including 150-lb payload). The sustainer stage was a little more than 20-feet in length and 15-inches in diameter. The launch weight of the booster was roughly 50 lbs more than that of the sustainer.
The X-8 was launched from a 143-foot tower which was typically canted 3-degrees off of the vertical. Booster burnout occurred at 950 ft/sec and 1,000 feet above the ground. Sustainer burnout took place at 4,420 ft/sec and an altitude of 17-nm. Apogee was on the order of 66-nm.
The Aerobee carried a variety of scientific instruments to probe the atmospheric and space environments. Measurements were made of high altitude thermodynamic properties, winds, radiation and magnetic fields. The Aerobee Program also provided a wealth of information regarding vehicle aerodynamics, flight dynamics and dispersion.
The Aerobee was also used to loft live biological payloads into near space. At the time this flight research began in the late 1940’s/early 1950’s, very little was known about the effects of high altitude rocket flight on living organisms. A variety of small animals were used as test subjects including primates, mice, and insects. The data obtained from these animal flights were ultimately used to safely launch men into space.
History records that it was not all that easy to rocket animals into space and have them survive the experience. Animals died either due to the rigors of rocket flight, launch vehicle failure or recovery system malfunction. Sometimes everything worked, but an animal died due to heat exhaustion when recovery crews could not extract it from the downed payload section soon enough. It would take over 3-years of flight experience before success was achieved.
The great day came on Thursday, 20 September 1951. An Aerobee X-8 RTV-A1 served as the launch platform. The live biological payload consisted of a monkey named Yorick and a colony of eleven (11) mice. The launch took place at 15:31 UTC from Holloman Air Force Base, New Mexico. The X-8 carried the monkey and mice payload to an apogee of 236,000 feet. The parachute recovery system finally worked. Recovery was also successful.
Many more successful Aerobee animal flights took place in the ensuing years. Even as Aerobee rocket performance increased significantly as numerous variants of the X-8 were developed over the life of the program. Indeed, almost 1,100 payloads were lofted into the realms above by the time the Aerobee was taken out of active service in 1985.
Fifty-two years ago this week, the United States Air Force successfully conducted an Initial Operational Capability Demonstration (IOC DEMO) of the Atlas D Intercontinental Ballistic Missile (ICBM). The Atlas Missile System was pronounced operational following the successful launch from Vandenberg Air Force Base, California.
Named for the superhuman strongman of Greek mythology, Atlas was the United States’ first operationally deployed intercontinental ballistic missile (ICBM). Program roots go back to 1946 when Consolidated Vultee Aircraft (Convair) was awarded a study contract by the United States Army Air Forces for a 1,500 to 5,000 mile range missile that could carry a nuclear warhead.
At the time Convair began its study, no missile within conception could carry even the smallest nuclear warhead available at the time. However, a confluence of technological developments in the early 1950’s led to Atlas becoming a high priority development within the United States defense community. First, the thermonuclear weapon was successfully demonstrated. Second, a design breakthrough occurred wherein nuclear warhead mass was sharply reduced. Finally, CIA activities revealed that the Soviet Union was making significant progress with their own ICBM program.
Atlas A, B and C were the initial test and development variants of America’s first ICBM. Atlas D was the first operational version. Configured with a Mark 2 reentry vehicle, it measured 75 feet in length and 10 feet in diameter. Atlas D weighed 255,000 lbs at launch and had a range of 10,360 miles.
The Atlas propulsion system consisted of a single Rocketdyne LR105 sustainer (57,000 lbs thrust) and a pair of Rocketdyne LR89 boosters (150,000 lbs thrust each). Roll control and fine velocity control was provided by a pair of Rocketdyne LR101 vernier rocket engines (1,000 lbs thrust each).
The Atlas sustainer rocket engine was mounted between the outboard booster rocket engines. This trio of rocket engines was ignited at launch. While the boosters were jettisoned around 130 seconds into flight, the sustainer core continued to fire until propellant exhaustion. This unique arrangement made Atlas a stage-and-a-half launch vehicle.
In striving for the minimum weight solution, the Atlas airframe included propellant tankage constructed of very thin stainless steel. This so-called “balloon tank” design required internal pressurization with nitrogen gas at about 5 psig to provide structural rigidity. An Atlas launch vehicle would simply collapse under its own weight if not so pressurized.
Atlas A, B, C and D variants employed radio guidance. That is, the missile sent position information from its guidance system to the ground via radio. In turn, the ground sent course correction information back to the missile. Starting with the Atlas E, the guidance system was entirely autonomous.
On Wednesday, 09 September 1959, the Strategic Air Command (SAC) conducted an Initial Operational Capability Demonstration (IOC DEMO) launch at Vandenberg Air Force Base, California. The Atlas D 12D launch vehicle lifted-off from Launch Complex 576-A2 at 17:50 UTC. Its Mark II reentry vehicle flew 4,480 nautical miles downrange and landed less than 1 nautical mile from its target near Wake Island. Apogee and maximum speed were 972 nautical miles and 16,000 mph, respectively.
The Atlas IOC DEMO mission was entirely successful. General Thomas D. Power, SAC Commander-in-Chief, was so impressed with the results of the flight that he immediately declared the Atlas System to be operational.
The Atlas missile ultimately stood sentinel at 11 separate launch sites located throughout the United States. Roughly 350 Atlas missiles were manufactured during the program’s lifetime, with a maximum of 129 missiles being deployed at any one time being 129. However, the introduction of the famous Minuteman missile in 1963 sounded the death knell for Atlas. Indeed, there were no more operational Atlas missiles after April of 1965.
Although its operational service life was somewhat brief, Atlas provided a proving ground for a multiplicity of emerging missile technologies. Further, Atlas development served as the organizational and procedural template for all future ICBM programs.
Following retirement from active ICBM service, depostured Atlas ICBM’s were converted to the space launch role. It was employed for nearly a quarter of a century in such capacity. Indeed, all Mercury Earth-orbital missions were launched using man-rated Atlas launch vehicles.
The Atlas is still active in the US launch vehicle inventory. Although now manufactured by Lockeed-Martin and having a configuration quite distinct from that of its ICBM forbears, the latest version of the venerable vehicle is the Atlas V. This modern Atlas variant can send nearly 65,000 lbs of payload into LEO and 29,000 lbs into GTO.
Fifty-five years ago this week, the USAF/Boeing KC-135A Stratotanker took to the skies for the first time. The jet-powered aircraft would go on to become the most famous military tanker in the history of aviation.
The KC-135A Stratotanker was a derivative of the famous Boeing Model 367-80. The type was the only jet-powered aircraft designed specifically for the aerial refueling mission. As such, it replaced the older and slower propeller-driven KC-97 Stratotanker. For the first 15 years of its operational life, the KC-135 was the only tanker flown by the Strategic Air Comman (SAC).
The KC-135A measured 136.25 feet in length and had a wingspan of 130.8 feet. Gross take-off weight and empty weight were 297,000 lbs and 109,000 lbs, respectively. Four (4) wing pylon-mounted Pratt and Whitney J57-P-59W turbojets provided a sea level thrust of 58,000 lbs in afterburner. The aircraft was designed to have an unrefueled range of 4,000 miles, a cruise speed of 552 mph and an operational ceiling of 40,000 feet.
Jet fuel was carried internally within six (6) wing tanks and four (4) fuselage tanks. All but 1,000 gallons of this fuel could be pumped to the receiver aircraft via an extendable boom located at the rear of the tanker. The KC-135 boom operator would lie in a prone position and actually flew the boom into the receiving aircraft’s fuel receptacle.
On Friday, 31 August 1956, the first KC-135A Stratotanker production aircraft made its maiden flight from the Boeing airfield at Renton, Washington. Known as the “The City of Renton”, this aircraft was the first of 820 KC-135 aircraft that Boeing would ultimately produce. Roughly 90 percent of these production aircraft were true tankers while the remainder were employed as cargo transports and flying command posts.
The service that the KC-135 has provided to our nation’s aerial warfighters has truly been astounding. For example, during nine years of the Vietnam conflict, KC-135s made 813,000 aerial refuelings of combat aircraft. In support of the Persian Gulf conflict, KC-135 tankers made 18,700 hookups and transferred 278,000,000 lbs of fuel.
The KC-135 has evolved into numerous variants over the course of its long operational life. A variety of modifications have extended the service life of the KC-135 into its sixth decade. Key upgrades include reskinning the wings with an improved aluminum alloy and more powerful and fuel-efficient CFM-56 turbofans. Total sea level thrust is more than 90,000 lbs in afterburner.
As a tribute to this venerable aircraft, her designers and her flight crews, we note here that the KC-135 Stratotanker remains the primary USAF aerial refueling aircraft to this very day.
Fifty-seven years ago this month, USAF Major Arthur W. “Kit” Murray set a new world altitude record of 90,440 feet in the rocket-powered Bell X-1A. In doing so, Murray reported that he could detect the curvature of the Earth from the apex of his trajectory.
The USAF/Bell X-1A was designed to explore flight beyond Mach 2. The craft measured 35.5 feet in length and had a wing span of 28 feet. Gross take-off weight was 16,500 pounds. Power was provided by an XLR-11 rocket motor which produced a maximum sea level thrust of 6,000 lbs. This powerplant burned 9,200 pounds of propellants (alcohol and liquid oxygen) in about 270 seconds of operation.
Similar to other early rocket-powered X-aircraft such as the Bell XS-1, Douglas D-558-II, Bell X-2 and North American X-15, the X-1A flew two basic types of high performance missions. That is, the bulk of the vehicle’s propulsive energy was directed either in the horizontal or in the vertical. The former was known as the speed mission while the latter was called the altitude mission.
On Saturday, 12 December 1953, USAF Major Charles E. “Chuck” Yeager flew the X-1A (S/N 48-1384) to an unofficial speed record of 1,650 mph (Mach 2.44). Moments after doing so, the X-1A went divergent in all three axes. The aircraft tumbled and gyrated through the sky. Control inputs had no effect. Yeager was in serious trouble. He could not control his aircraft and punching-out was not an option. The X-1A had no ejection seat.
Chuck Yeager took a tremendous physical and emotional beating for more than 70 seconds as the X-1A wildly tumbled. His helmet hit the canopy and cracked it. He struck the control column so hard that it was physically bent. His frantic air-to-ground communications were distinctly those of a man who was convinced that he was about to die.
As the X-1A tumbled, it decelerated and lost altitude. At 33,000 feet, a battered and groggy Yeager found himself in an inverted spin. The aircraft suddenly fell into a normal spin from which Yeager recovered at 25,000 feet over the Tehachapi Mountains situated northwest of Edwards. Somehow, Yeager managed to get himself and the X-1A back home intact.
The culprit in Yeager’s wide ride was the then little-known phenomenon identified as roll inertial coupling. That is, inertial moments produced by gyroscopic and centripetal accelerations overwhelmed aerodynamic control moments and thus caused the aircraft to depart controlled flight. Roll rate was the critical mechanism since it coupled pitch and yaw motion.
In the aftermath of Yeager’s near-death experience in the X-1A, the Air Force ceased flying speed missions with the aircraft. Instead, a series of flights followed in which the goal was to extract maximum altitude performance from the aircraft. USAF Major Arthur W. “Kit” Murray was assigned as the Project Pilot for these missions.
On Thursday, 26 August 1954, Kit Murray took the X-1A (S/N 48-1384) to a maximum altitude of 90,440 feet. This was new FAI record. Murray also ran into the same roll inertial coupling phenomena as Yeager. However, his experience was less tramatic than was Yeager’s. This was partly due to the fact that Murray had the benefit of learning from Yeager’s flight. This allowed him to both anticipate and know how to correct for this flight disturbance.
Murray’s achievement in the X-1A meant that the X-1A held the records for both maximum speed and altitude for manned aircraft. It did so until both records were eclipsed by the Bell X-2 in September of 1956.
Kit Murray was a highly accomplished test pilot who never received the public adulation and notoreity that Chuck Yeager did. He retired from the Air Force in 1960 after serving for 20 years in the military. Murray went on to a very successful career in engineering following his military service. Kit Murray lived to the age of 92 and passed from this earthly scene on Monday, 25 July 2011.
Fifty-four years ago this week, USAF Major David G. Simons, MD successfully completed the Manhigh II high-altitude balloon mission. Simons’ epic flight lasted 32 hours and established an altitude record of 101,516 feet.
Project Manhigh was a United States Air Force biomedical research program that investigated the human factors of spaceflight by taking men into a near-space environment. Preparations for the trio of Manhigh flights began in 1955. The experience and data gleaned from Manhigh were instrumental to the success of the nation’s early manned spaceflight effort.
The Manhigh target altitude was approximately 100,000 feet above sea level. A helium-filled polyethylene balloon, just 0.0015-inches thick and inflatable to a maximum volume of over 3-million cubic feet, carried the Manhigh gondola into the stratosphere. At float altitude, this balloon expanded to a diameter of about 200 feet.
The Manhigh gondola was a hemispherically-capped cylinder that measured 3-feet in diameter and 8-feet in length. It was attached to the transporting balloon via a 40-foot diameter recovery parachute. Although compact, the gondola was amply provisioned with the necessities of flight including life support, power and communication systems. It also included expendable ballast for use in controlling the altitude of the Manhigh balloon.
The Manhigh test pilot wore a T-1 partial pressure suit during the Manhigh mission. This would protect him in the event that the gondola cabin lost pressure at extreme altitude. The pilot was hooked-up to a variety of sensors which transmitted his biomedical information to the ground throughout the flight. This allowed medicos on the ground to keep a constant tab on the pilot’s physical status.
The flight of Manhigh I took place on Sunday, 02 June 1957 with USAF Captain Joseph W. Kittinger as pilot. Kittinger reached an altitude of 95,200 feet. Though successful in the main, the mission was cut short due to rapid depletion of the oxygen supply. This was caused by accidental crossing of the oxygen supply and vent lines prior to flight. Total mission time was 6 hours and 32 minutes.
Manhigh II was launched at 1422 UTC from Portmouth Mine in Crosby, Minnesota on Sunday, 18 August 1957. USAF Major David G. Simons, a medical doctor, flew this nominally 24-hour mission. Simons uneventful ascent to Flight Level 1,000 took 2 hours and 18 minutes. A maximum altitude of 101,516 feet was ultimately recorded during Manhigh II.
Simons’ flight was taxing both physically and mentally. Cabin environmental management issues and the frequent need to monitor and control atitude so as to remain sufficiently above thunderstorm activity were the primary stressors. However, the pilot dutifully went about conducting a variety of more than 25 different scientific experiments. Simon’s flight came to a successful conclusion when his gondola landed in an alfalfa field near Frederick, South Dakota at 22:32 UTC on Monday, 19 August 1957.
By way of postscript, Manhigh III was successfully conducted on Wednesday, 08 October 1958. Launch occurred at Holloman AFB, New Mexico with USAF Lt Clifton M. McClure as pilot. The mission’s success was largely due to McClure’s super-human efforts in overcoming a variety of life-threatening problems. However, that story will be reserved for another day.
The contributions made to aero medical science by the Manhigh Program were significant. Indeed, information gleaned from this flight research effort tangibly influenced future manned flight including the X-15 Program, Project Excelsior and Project Mercury. To get a fuller appreciation for Manhigh’s significance in aerospace history, the interested reader is invited to read Simons 1962 book aptly entitled “Manhigh”.
David Simons continued to serve his country as an officer in the United States Air Force for another 8 years following his Manhigh II flight. He retired from the junior service in 1965 as a Lieutenant Colonel. In civilian life, he went on to become an internationally-recognized expert in the treatment of chronic pain. In April of 2010, Simons left this frail existence while in his 88th year.
Fifty-one years ago this month, an United States Air Force C-119 Flying Boxcar aircraft successfully performed the first mid-air retrieval of a reentry body as it was returning from space. The recovered vehicle was named Discoverer XIV.
Corona was a covert reconnaissance program operated by the United States government from June of 1959 to May of 1972. The national security mission was to photographically surveil denied territory from orbit. The exposed film was then returned to Earth via a reentry capsule and recovered for subsequent development and photogrammetric analysis.
An evolutionary series of satellites, code named Key Hole (KH), were flown during the Corona Program. A total of 144 satellites were flown over the course of the surveillance effort; 71% of which provided useful results. Although not addressed here, the history of the development of the Key Hole camera system is a fascinating story in its own right.
A Corona satellite orbited the Earth at altitudes between 89 and 250 nautical miles. From its perch high in the heavens, the orbiting eye-in-the-sky exposed almost 6 statute miles of film during a typical mission. The camera systems used early in the Corona Program provided a target resolution of 25 feet. Later systems delivered a resolution of 6 feet.
The Discoverer Program served as a public front for Corona. Labled as a space technology development program, Discoverer was in fact used to fly the early Key Hole camera systems. The satellite also served as the means to develop and refine mid-air retrieval techniques for recovery of the Corona film canister. The last Discoverer mission (Discoverer XXXIX) was flown in April of 1962.
Successful recovery of the Corona film canister from orbit required precise targeting of the reentry vehicle. This would put the recovery aircraft in a position to make a mid-air retrieval. A special line suspension system deployed under the aircraft was used to snag the reentry vehicle as it slowly decended on its parachute. Once retrieved in this manner, the entire assemblage was reeled into the back of the recovery aircraft.
Success did not come easy for the Discoverer Program. The first dozen missions were failures for one reason or another. Either the satellite failed to achieve orbit or the recovery operation was unsuccessful. However, the importance of the mission was such that development flights continued.
Successful recovery of a Discoverer reentry capsule finally came on Thursday, 11 August 1960. Discoverer XIII had been boosted into a polar orbit by a Thor-Agena launch vehicle the previous day and had orbited the Earth 17 times before its return from space. Despite excellent placement into the target area, successful mid-air retrieval of the reentry vehicle did not occur. Navy frogmen had to fish Discoverer XIII out of the water.
Discoverer XIV was launched into space by a Thor-Agena launch vehicle on Thursday, 18 August 1960. After 17 polar orbits, the reentry vehicle returned to Earth on Friday, 19 August 1960. The mission was very successful including the mid-air retrieval operation. Interestingly, it wasn’t until the 3rd pass that the C-119 Flying Box Car from the 6593rd Test Squadron at Hickam AFB, Hawaii successfully made the grab. Nevertheless, Discoverer XIV became the first reentry vehicle in history to be recovered via mid-air retrieval.
The Corona Program went on to a highly successful operational life. The information gathered therein provided a tangible check on communist military activity and measurably improved the security of not only the United States, but that of the entire free world. Indeed, Corona was a key part of the national security apparatus at a time when the nuclear damocles hung in a particularly menacing manner over the heads of all those who hallow freedom.
Fifty-seven years ago this week, the USN/Convair YF2Y-1 Sea Dart became the first and only seaplane ever to exceed the speed of sound. Convair test pilot Charles E. Richbourg was at the controls of the experimental sea-based fighter.
In 1948, the United States was looking to develop a sea-based supersonic fighter as a means projecting naval airpower. However, few in the Navy at that time believed that such as aircraft could be operated successfully from an aircraft carrier. Thus, the new aircraft would need to be a seaplane That is, it would take-off and land in the ocean.
Consolidated Vultee Aircraft (Convair) won a competition for a Navy contract to build and flight test a pair of supersonic seaplane prototypes. Convair’s winning airframe featured a delta wing, a large triangular vertical tail, twin afterburning turbojets and dual retractable hydro-skis. Known as the XFY2-1 Sea Dart, the two protoype aircraft were assigned BuAer tail numbers 137634 and 137635, respectively.
The Sea Dart’s nominal specifications included a length of 52.5 ft, a wingspan of 33.7 ft and an empty weight of 12,625 lbs. The single-place aircraft was initially powered by twin Westinghouse J46-WE-2 turbojets. Each of these non-afterburning powerplants produced a meager 3,400 lbs of sea level thrust. This led to the aircraft being significantly underpowered.
The XF2Y-1 design maximum speed was 825 mph, a rate of climb of 17,000 ft/min and a service ceiling of nearly 55,000 ft. The type’s take-off speed from the water was approximately 145 mph. Although the prototypes were never outfitted with armament, an operational Sea Dart reportdely would have had a mix of 4 x 20mm cannon, a bevy of 2.75-inch unguided rockets and a pair of air-to-air missiles.
Convair test pilot Ellis D. Shannon made the official first flight of XF2Y-1 Ship No. 1 (BuAer 137634) on Thursday, 09 April 1953. San Diego Bay served as the take-off and landing site. Shannon quickly determined that the XF2Y-1 was indeed underpowered. The aircraft’s hydro-skis also vibrated badly during ocean take-off and landing. The result was that the XF2Y-1 was quite challenging to control during high-speed ocean surface operations.
The second Sea Dart to fly was the first YF2Y-1 (BuAer 135762)aircraft. The main difference between the YF2Y-1 and XF2Y-1 was the propulsion system. Specifically, the YF2Y-1 was powered by afterburning J46 turbojets and its air induction and exhaust systems were configured differently. With the introduction of the YF2Y-1, the XF2Y-1 was cancelled by the Navy.
Flight testing of the YF2Y-1 Sea Dart began in early 1954. Convair test pilot Charles E. Richbourg was assigned to make the initial flights in Ship No. 1. The zenith of the YF2Y-1’s flight test program occurred on Tuesday, 03 August 1954 when Richbourg flew the seaplane faster than the speed of sound while passing through 34,000 feet in a shallow dive. This event marked the first and only time in aviation history that a seaplane exceeded Mach 1.
The Sea Dart’s bright moment of achievement was followed several months later by the program’s darkest day. On Thursday, 04 November 1954, Richbourg was performing a XF2Y-1 flight demonstration for Navy leadership and members of the press over San Diego Bay when structural failure of the aircraft’s left wing caused it to distintegrate in flight. Rescue forces quickly found Richbourg and pulled him out of the water. However, the 31 year-old pilot did not survive.
The loss of the first YF2Y-1 came at a time when the Navy was already losing interest in the Sea Dart Program. The service had rethought the notion of operating a high-performance aircraft from its carrier force and now reckoned that such operations were indeed possible. These realities, coupled with the Sea Dart’s seemingly unsolvable hydro-ski vibration problems, effectively sounded the death knell of Convair’s supersonic seaplane concept.
Notwithstanding the above, it would not be until the fall of 1957 that the Sea Dart Program would officially come to an end. Actually, three (3) more YF2Y-1 airframes were manufactured. Sea Dart Ship No. 3 (BuAer 13563) flew for the first time on Friday, 04 March 1955. This aircraft was used mainly for flight testing various hydro-ski arrangements. Sea Dart Ship No. 4 (BuAer 135764) and Ship No. 5 (BuAer 135765) never flew.
Sixty-one years ago this month, the United States Army’s Bumper-WAC No. 7 two-stage rocket reached a maximum speed of 8,213 ft/sec (Mach 9). This concluding flight of the Bumper Program was flown from the Long-Range Proving Ground (LRPG) in Florida.
The Bumper Program was a United States Army effort to reach flight altitudes and velocities never before achieved by a rocket vehicle. The name “Bumper” was derived from the fact that the lower stage would act to “bump” the upper stage to higher altitude and velocity than it (i.e., the upper stage) was able to achieve on its own.
The Bumper Program, which was actually part of the Army’s Project Hermes, officially began on Friday, 20 June 1947. The project team consisted of the General Electric Company, Douglas Aircraft Company and Cal Tech’s Jet Propulsion Laboratory. A total of eight (8) test flights took place between May 1948 and July 1950.
The Bumper two-stage configuration consisted of a V-2 booster and a WAC Corporal upper stage. The V-2′s had been captured from Germany following World War II while the WAC Corporal was a single stage American sounding rocket. The launch stack measured 62 feet in length and weighed around 28,000 pounds.
Propulsion-wise, the V-2 booster generated 60,000 pounds of thrust with a burn time of 70 seconds. The WAC Corporal rocket motor produced 1,500 pounds of thrust and had a burn time of 47 seconds.
The flight of Bumper-WAC No. 1 occurred on Thursday, 13 May 1948. This was an engineering test flight in which the WAC Corporal achieved a peak altitude of 79 miles. Unfortunately, the next three (3) flights were plagued by development problems of one kind or another and failed to achieve an altitude of even 10 miles.
Bumper-WAC No. 5 was fired from WSPG on Thursday, 24 February 1949. The V-2 burned-out at an altitude of 63 miles and a velocity of 3,850 feet per second. The WAC Corporal accelerated to a maximum velocity of 7,550 feet per second and then coasted to an apogee of 250 miles. With generation of a very thin bow shock layer and high aerodynamic surface heating levels, this flight can be considered as the first time a man-made flight vehicle entered the realm of hypersonic flight.
Three (3) more Bumper-WAC missions would follow Bumper-WAC No.5. While Bumper-WAC No. 6 would fly from WSPG, the final two (2) missions were conducted from an isolated Florida launch site in July of 1950. The hot, bug-infested Floridian launch location, springing-up amongst sand dunes and scrub palmetto, would one day become the seat of American spaceflight. It was known then as the Long-Range Proving Ground (LRPG). Today, we know it as Cape Canaveral.
Bumper-WAC No. 7 was supposed to be the first rocket fired from the LRPG. However, Bumper-WAC No. 8 got that honor when No. 7 experienced a glitch on the pad. No. 8 was fired at 13:29 UTC on Monday, 24 July 1950. The mission failed when the rocket motor of the WAC upper stage did not ignite.
On Saturday, 29 July 1950, Bumper-WAC No. 7 was launched from the LRPG. The resulting flight achieved the highest kinematic performance of the Bumper Program. The WAC upper stage burned-out at 8,213 ft/sec (Mach 9) and flew 150 miles downrange. The maximum velocity within the atmosphere was more than 3,200 mph – a record for the time.
The Bumper Program successfully demonstrated the efficacy of the multi-staging concept. Bumper also provided valuable flight experience in stage separation and high altitude rocket motor ignition systems. In short, Bumper played a vital role in helping America successfully develop its ICBM, satellite and manned spaceflight capabilities.
While its historical significance, and even its existence, has been lost to many here in the 21st Century, the Bumper Program played a major role in our quest for the Moon. As such, it will forever hold a hollowed place in the annals of United States aerospace history.
Fifty-years ago this week, Mercury Seven Astronaut Vigil I. “Gus” Grissom, Jr. became the second American to go into space. Grissom’s suborbital mission was flown aboard a Mercury space capsule that he named Liberty Bell 7.
The United States first manned space mission was flown on Friday, 05 May 1961. On that day, NASA Astronaut Alan B. Shepard, Jr. flew a 15-minute suborbital mission down the Eastern Test Range in his Freedom 7 Mercury spacecraft. Known as Mercury-Redstone 3, Shepard’s mission was entirely successful and served to ignite the American public’s interest in manned spaceflight.
Shepard was boosted into space via a single stage Redstone rocket. This vehicle was originally designed as an Intermediate-Range ballistic Missile (IRBM) by the United States Army. It was man-rated (that is, made safer and more reliable) by NASA for the Mercury suborbital mission. A descendant of the German V-2 missile, the Redstone produced 78,000 lbs of sea level thrust.
Shepard’s suborbital trajectory resulted in an apogee of 101 nautical miles (nm). With a burnout velocity of 7,541 ft/sec, Freedom 7 splashed-down in the Atlantic Ocean 263 nm downrange of its LC-5 launch site at Cape Canaveral, Florida. Shepard endured a maximum deceleration of 11 g’s during the reentry phase of the flight.
Mercury-Redstone 4 was intended as a second and confirming test of the Mercury spacecraft’s space-worthiness. If successful, this mission would clear the way for pursuit and achievement of the Mercury Program’s true goal which was Earth-orbital flight. All of this rested on the shoulders of Gus Grissom as he prepared to be blasted into space.
Grissom’s Liberty Bell 7 spacecraft was a better ship than Shepard’s steed from several standpoints. Liberty Bell 7 was configured with a large centerline window rather than the two small viewing ports featured on Freedom 7. The vehicle’s manual flight controls included a new rate stabilization system. Grissom’s spacecraft also incorporated a new explosive hatch that made for easier release of this key piece of hardware.
Mercury-Redstone 4 (MR-4) was launched from LC-5 at Cape Canaveral on Friday, 21 July 1961. Lift-off time was 12:20:36 UTC. From a trajectory standpoint, Grissom’s flight was virtually the same as Shepard’s. He found the manual 3-axis flight controls to be rather sluggish. Spacecraft control was much improved when the new rate stabilization system was switched-on. The time for retro-fire came quickly. Grissom invoked the retro-fire sequence and Liberty Bell 7 headed back to Earth.
Liberty Bell 7’s reentry into the Earth’s atmosphere was conducted in a successful manner. The drogue came out at 21,000 feet to stabilize the spacecraft. Main parachute deployed occurred at 12,300 feet. With a touchdown velocity of 28 ft/sec, Grissom’s spacecraft splashed-down in the Atlantic Ocean 15 minutes and 32 seconds after lift-off. America now had both a second spaceman and a second successful space mission under its belt.
Following splashdown, Grissom logged final switch settings in the spacecraft, stowed equipment and prepared for recovery as several Marine helicopters hovered nearby. As he did so, the craft’s new explosive hatch suddenly blew for no apparent reason. Water started to fill the cockpit and the surprised astronaut exited the spacecraft as quickly as possible.
Grissom found himself outside his psacecraft and in the water. He was horrfied to see that Liberty Bell 7 was in imminent peril of sinking. The primary helicopter made a valiant effort to hoist the spacecraft out of the water, but the load was too much for it. Faced with losing his vehicle and crew, the pilot elected to release Liberty Bell 7 and abandon it to a watery grave.
Meanwhile, Grissom struggled just to stay afloat in the churning ocean. The prop blast from the recovery helicopters made the going even tougher. Finally, Grissom was able to retrieve and get himself into a recovery sling provided by one of the helicopters. He was hoisted aboard and subsequently delivered safely to the USS Randolph.
In the aftermath of Mercury-Redstone 4, accusations swirled around Grissom that he had either intentionally or accidently hit the detonation plunger that activated the explosive hatch. Always the experts on everything, especially those things they have little comprehension of, the denizens of the press insinuated that Grissom must have panicked. Grissom steadfastly asserted to the day that he passed from this earthly scene that he did no such thing.
Liberty Bell 7 rested at a depth of 15,000 feet below the surface of the Atlantic Ocean until it was recovered by a private enterprise on Tuesday, 20 July 1999; a day short of the 38th anniversary of Gus Grissom’s MR-4 flight. The beneficiary of a major restoration effort, Liberty Bell 7 is now on display at the Kansas Cosmosphere and Space Center. The spacecraft’s explosive hatch was never found.
As for Gus Grissom, ultimate vindication of his character and competence came in the form of his being named by NASA as Commander for the first flights of Gemini and Apollo. Indeed, Grissom and rookie astronaut John W. Young successfully made the first manned Gemini flight in March of 1965 during Gemini-Titan 3. Later, Grissom, Edward H. White II and Roger B. Chaffee trained as the crew of Apollo 1 which was slated to fly in early 1967. History records that their lives were cut short in the tragic and infamous Apollo 1 Spacecraft Fire of Friday, 27 January 1967.
Fifty-six years ago this month, the USAF/Republic XF-84H experimental turboprop fighter took to the air for the first time. The test hop originated from and recovered at Edwards Air Force Base, California.
The turbojet-powered XF-84H was a variant of Republic Aviation’s F-84 Thunderstreak. An Allison XT40-A-1 turboprop engine, rated at 5,850 hp, served as the power source for this novel aircraft. The XT40 drove a variable-pitch, 3-blade, 12-foot diameter propeller at 3,000 rpm. Thrust level was changed by varying blade pitch.
Owing to its high rotational speed and large diameter, the outer 2 feet of the XF-84H propeller saw supersonic velocities. The shock waves that emanated from the prop produced a deafening wall of sound. The extreme sound level produced intense nausea and raging headaches in ground crewmen. As a result, the XF-84H was dubbed the “Thunderscreech”.
The prop wash from the aircraft’s powerful turboprop necessitated the use of a T-tail to keep the horizontal tail and elevator in clean air flow. The engine’s extreme torque was partially countered by differential deflection on the left and right wing flaps and by placement of the left wing root air intake a foot ahead of the right intake.
A pair of XF-84H prototype aircraft (S/N 51-17059 and S/N 51-17060) was built by Republic Aviation. The first flight of an XF-84H took place on Friday, 22 July 1955 at Edwards Air Force. The flight was made by Republic test pilot Henry G. “Hank” Beaird, Jr. in Ship No. 1 (S/N 51-17059). The flight was cut short by a forced landing.
A total of twelve (12) test flights were made in the two Thunderscreech prototypes; eleven (11) in Ship No. 1 and one (1) in Ship No. 2. Total flight time accumulated by these experimental airframes was 6 hours and 40 minutes. The majority of flights experienced forced landings for one reason or another.
The XF-84H suffered from reduced longitudinal stability and poor handling qualities. The aircraft was also plagued by frequent engine, hydraulic system, nose gear and vibration problems. Faced with the type’s obvious non-viability, USAF opted to cancel the XF-84H Program in September of 1956.
Historical records indicate that the XF-84H reached a top speed of 520 mph during its brief flight test life. This figure was a full 120 mph short of the aircraft’s design speed. Nonetheless, the XF-84H held the speed record for single-engine prop-driven aircraft until Monday, 21 August 1989. On that date, a specially modified Grumman F8F Bearcat established the existing record of 528.33 mph.
Twenty-nine years ago today, the Space Shuttle Columbia landed at Edwards Air Force Base to successfully conclude the fourth orbital mission of the Space Transportation System. Columbia’s return to earth added a special touch to the celebration of America’s 207th birthday.
STS-4 was NASA’s fourth Space Shuttle mission in the first fourteen months of Shuttle orbital flight operations. The two-man crew consisted of Commander Thomas K. Mattingly, Jr. and Pilot Henry W. Hartsfield who were both making their first Shuttle orbital mission. STS-4 marked the last time that a Shuttle would fly with a crew of just two.
STS-4 was launched from Cape Canaveral’s LC-39A on Sunday, 27 June 1982. Lift-off was exactly on-time at 15:00:00 UTC. Interestingly, this would be the only occasion in which a Space Shuttle would launch precisely on-time. The Columbia weighed a hefty 241,664 lbs at launch.
Mattingly and Hartsfield spent a little over seven (7) days orbiting the Earth in Columbia. The orbiter’s cargo consisted of the first Getaway Special payloads and a classified US Air Force payload of two missile launch-detection systems. In addition, a Continuous Flow Electrophoresis System (CFES) and the Mono-Disperse Latex Reactor (MLR) were flown for a second time.
The Columbia crew conducted a lightning survey using manual cameras and several medical experiments. Mattingly and Hartsfield also maneuvered the Induced Environment Contamination Monitor (IECM) using the Orbiter’s Remote Manipulator System (RMS). The IECM was used to obtain information on gases and particles released by Columbia in flight.
On Sunday, 04 July 1982, retro-fire started Columbia on its way back to Earth. Touchdown occurred on Edwards Runway 22 at 16:09:31 UTC. This landing marked the first time that an Orbiter landed on a concrete runway. (All three previous missions had landed on Rogers Dry Lake at Edwards.) Columbia made 112 complete orbits and traveled 2,537,196 nautical miles during STS-4.
The Space Shuttle was declared “operational” with the successful conduct of the first four (4) shuttle missions. President Ronald Reagan and First Lady Nancy Reagan even greeted the returning STS-4 flight crew on the tarmac. However, as history has since taught us, manned spaceflight still comes with a level of risk and danger that exceeds that of military and commercial aircraft operations. It will be some time before a manned space vehicle is declared operational in the desired sense.
Fifty-three years ago this week, the United States Army Nike Hercules air defense missile system was first deployed in the continental United States. The second-generation surface-to-air missile was designed to intercept and destroy hostile ballistic missiles.
The Nike Program was a United States Army project to develop a missile capable of defending high priority military assets and population centers from attack by Soviet strategic bombers. Named for the Greek goddess of victory, the Nike Program began in 1945. The industrial consortium of Bell Laboratories, Western Electric, Hercules and Douglas Aircraft developed, tested and fielded Nike for the Army.
Nike Ajax (MIM-3) was the first defensive missile system to attain operational status under the Nike Program. The two-stage, surface-launched interceptor initially entered service at Fort Meade, Maryland in December of 1953. A total of 240 Nike Ajax launch sites were eventually established throughout CONUS. The primary assets protected were metropolitan areas, long-range bomber bases, nuclear plants and ICBM sites.
Nike Ajax consisted of a solid-fueled first stage (59,000 lbs thrust) and a liquid-fueled second stage (2,600 lbs thrust). The launch vehicle measured nearly 34 feet in length and had a ignition weight of 2,460 lbs. The second stage was 21 feet long, had a maximum diameter of 12 inches and weighed 1,150 lbs fully loaded. The type’s maximum speed, altitude and range were 1,679 mph, 70,000 feet and 21.6 nautical miles, respectively.
The Nike Hercules (MIM-14) was the successor to the Nike Ajax. It featured all-solid propulsion and much higher thrust levels. The first stage was rated at 220,000 lbs of thrust while that of the second stage was 10,000 lbs. The Nike Hercules airframe was significantly larger than its predecessor. The launch vehicle measured 41 feet in length and weighed 10,700 lbs at ignition. Second stage length and ignition weight were 26.8 feet and 5,520 lbs, respectively.
Nike Hercules kinematic performance was quite impressive. The respective top speed, altitude and range were 3,000 mph, 150,000 feet and 76 nautical miles. This level of performance allowed the vehicle to be used for the ballistic missile intercept mission. Most Nike Hercules missiles carried a nuclear warhead with a yield of 20 kilotons.
The first operational Nike Hercules systems were deployed to the Chicago, Philadelphia and New York localities on Monday, 30 June 1958. By 1963, fully 134 Nike Hercules batteries were deployed throughout CONUS. These systems remained in the United States missile arsenal until 1974. The exceptions were batteries located in Alaska and Florida which remained in active service until the 1978-79 time period.
Like Nike Ajax before it, Nike Hercules had a successor. It was originally known as Nike Zeus and then Nike-X. This Nike variant was designed for intercepting enemy ICBM’s that were targeted for American soil. The vehicle went through a number of iterations before a final solution was achieved. Known as Spartan, this missile was what we would refer to today as a mid-course interceptor.
In companionship with a SPRINT terminal phase interceptor, Spartan formed the Safeguard Anti-Ballistic Missile System. The American missile defense system was impressive enough to the Soviet Union that the communist country signed the Anti-Ballistic Missile (ABM) Treaty 3 years before Safeguard’s deployment. Though operational for a mere 3 months, Safeguard was depostured in 1975. This action brought to a close a 30-year period in which the Nike Program was a major player in American missile defense.
Ten years ago this month, the first NASA X-43A airframe-integrated scramjet flight research vehicle was launched from a B-52 carrier aircraft high over the Pacific Ocean. The inaugural mission of the HYPER-X Flight Project came to an abrupt end when the launch vehicle departed controlled flight while passing through Mach 1.
In 1996, NASA initiated a technology demonstration program known as HYPER-X (HX). The central goal of the HYPER-X Program was to successfully demonstrate sustained supersonic combustion and thrust production of a flight-scale scramjet propulsion system at speeds up to Mach 10.
Also known as the HYPER-X Research Vehicle (HXRV), the X-43A aircraft was a scramjet test bed. The aircraft measured 12 feet in length, 5 feet in width, and weighed close to 3,000 pounds. The X-43A was boosted to scramjet take-over speeds with a modified Orbital Sciences Pegasus rocket booster.
The combined HXRV-Pegasus stack was referred to as the HYPER-X Launch Vehicle (HXLV). Measuring approximately 50 feet in length, the HXLV weighed slightly more than 41,000 pounds. The HXLV was air-launched from a B-52 mothership. Together, the entire assemblage constituted a 3-stage vehicle.
The first flight of the HYPER-X program took place on Saturday, 02 June 2001. The flight originated from Edwards Air Force Base, California. Using Runway 04, NASA’s venerable B-52B (S/N 52-0008) started its take-off roll at approximately 19:28 UTC. The aircraft then headed for the Pacific Ocean launch point located just west of San Nicholas Island.
At 20:43 UTC, the HXLV fell away from the B-52B mothership at 24,000 feet. Following a 5.2 second free fall, the rocket motor lit and the HXLV started to head upstairs. Disaster struck just as the vehicle accelerated through Mach 1. That’s when the rudder locked-up. The launch vehicle then pitched, yawed and rolled wildly as it departed controlled flight. Control surfaces were shed and the wing was ripped away. The HXRV was torn from the booster and tumbled away in a lifeless state. All airframe debris fell into the cold Pacific Ocean far below.
The mishap investigation board concluded that no single factor caused the loss of HX Flight No. 1. Failure occurred because the vehicle’s flight control system design was deficient in a number of simulation modeling areas. The result was that system operating margins were overestimated. Modeling inaccuracies were identified primarily in the areas of fin system actuation, vehicle aerodynamics, mass properties and parameter uncertainties. The flight mishap could only be reproduced when all of the modeling inaccuracies with uncertainty variations were incorporated in the analysis.
The X-43A Return-to-Flight effort took almost 3 years. Happily, the HYPER-X Program hit paydirt twice in 2004. On Saturday, 27 March 2004, HX Flight No. 2 achieved scramjet operation at Mach 6.83 (almost 5,000 mph). This historic accomplishment was eclipsed by even greater success on Tuesday, 16 November 2004. Indeed, HX Flight No. 3 achieved sustained scramjet operation at Mach 9.68 (nearly 7,000 mph).
The historic achievements of the HYPER-X Program went largely unnoticed by the aerospace industry and the general public. For its part, NASA did not do a very good job of helping people understand the immensity of what was accomplished. Even the NASA Administrator appeared different to the scramjet program. While he attended an X-Prize flight by Scaled-Composites’ SpaceShipOne right up the street at the Mojave Spaceport, he did not see fit to attend either of that year’s historic scramjet flights that originated right down the street at Edwards Air Force base.
However, it was the loss of the Space Shuttle Columbia on STS-107 in February of 2003 that doomed HX even before the program’s first successful flight. Everything changed for NASA when Columbia and its crew was lost. The agency’s overriding focus and meager financial resources went into the Shuttle Return-to-Flight effort. NASA’s aeronautical and access-to-space arms were especially hard hit.
If timing is everything as some insist, then the HYPER-X Program was really the victim of bad timing. It is both intriguing and distressing to ponder what would have been the case if HX Flight No. 1 had been successful. The likely answer is that at least one of the anticipated follow-on scramjet flight research programs (i.e., X-43B, X-43C, and X-43D) would have been developed and flown. Thanks to Murphy’s ubiquitous influence, we’ll never know.
Sixty-three years ago this month, the USAF/Northrop YB-49 Flying Wing came apart during a test flight that originated at Muroc Air Force Base. Among the five crew members who perished in the aviation mishap was famed test pilot USAF Captain Glen W. Edwards.
The USAF/Northrop YB-49 heavy bomber prototype first flew in October of 1947. The aircraft was a jet-powered derivative of the propeller-driven XB-35. Both of these legendary aircraft were flying wing designs pioneered by visionary aircraft designer Jack Northrop.
Traditionally, interest in a flying wing aircraft stems from its inherently-high lift, low drag and hence high lift-to-drag ratio characteristics. These attributes make a flying wing ideal for the strategic bombing mission where large payloads must be carried long distances to the target. In addition, the type’s low profile and swept wings contributed to its low radar cross-section.
The same configurational features that give flying wing aircraft favorable performance also present stability and control issues and adverse handling qualities. The lack of a traditional empenage requires that all flight controls be placed on the wing itself. This leads to significant aerodynamic coupling that affects aircraft pitch, yaw and roll motion.
The YB-49 had a wing span of 172 feet, a length of 53 feet and a height of 15 feet. Gross take-off weight was approximately 194,000 lbs. Fuel accounted for roughly 106,000 lbs of that total. Power was supplied by eight (8) Allison/General Electric J35-A-5 turbojets. Each of these early-generation powerplants was rated at a mere 4,000 lbs of sea level thrust.
The YB-49 design performance included a maximum speed of 495 mph, a service ceiling of 45,700 feet and a maximum range of 8,668 nautical miles. The aircraft was designed to carry a maximum bomb load of 32,000 lbs. The strategic bombing mission would be flown by a crew of seven (7) including pilot, co-pilot, navigator, bombardier and gunners.
A pair of XB-35 airframes were modified to the YB-49 configuration. Ship No. 1 (S/N 42-102367) first took to the air on Tuesday, 21 October 1947. The maiden flight of Ship No. 2 (S/N 42-102368) occurred on Tuesday, 13 January 1948. Both flights originated from Hawthorne Airport and recovered at Muroc Air Force Base.
Flight testing of the YB-49 quickly confirmed the type’s performance promise. Demonstrated performance included a top speed of 520 mph and a maximum altitude of 42,000 feet. On Monday, April 26, 1948. On that date, the aircraft remained aloft for 9.5 hours, of which 6.5 hours were flown at an altitude of 40,000 feet.
The low point in YB-49 flight testing came on Saturday, 05 June 1948. On that fateful day, YB-49 Ship No. 2 crashed to destruction in the Mojave Desert northwest of Muroc Air Force Base. The entire crew of five (5) perished in the mishap. These crew members included Major Daniel N. Forbes (pilot), Captain Glen W. Edwards (co-pilot), Lt. Edward L. Swindell (flight engineer), Clare E. Lesser (observer) and Charles H. LaFountain (observer).
The cause of the YB-49 mishap was never fully determined. In descending from 40,000 feet following a test mission, the aircraft somehow exceeded its structural limit. The outer wing panels failed and the rest of the aircraft tumbled out of control, struck the ground inverted and immediately fireballed. Whether the incident was related to wing stall, spin or some such other flight control issue will never be definitively known.
YB-49 Ship No. 1 continued to fly after the loss of its stable mate. However, it too met an unkind fate. On Wednesday, 15 March 1950, the aircraft was declared a total loss following a non-fatal high-speed taxiing mishap. Several months later, all of Northrop’s flying wing contracts with the government were unexpectedly cancelled. Incredibly, the Wizards of the Beltway ultimately ordered that all Northrop-produced flying wing variants be cut-up for scrap.
Despite its performance, the YB-49 was too far ahead of its time. The aircraft did not exhibit good handling qualities and thus was not a good bombing platform. It needed the type of computer-based, multiply-redundant autopilot that is standard equipment on today’s aircraft.
Happily, the performance merits of the flying wing concept would be fully exploited with the introduction of the USAF/Northrop B-2 Advanced Technology Bomber (ATB). This aircraft first flew on Monday, 17 July 1989. Its subsequent success is now history. A host of new technologies converged to finally made the flying wing concept viable. Not the least of which is the aircraft’s multiply-redundant flight control system.
Finally, we note that 30-year old Captain Glen W. Edwards was a rising star in military flight test circles at the time of his death. In tribute to his aviation skills and in memory of a life cut short, Muroc Air Force Base was officially renamed on Tuesday, 05 December 1950. Since that day, it has been known as Edwards Air Force Base.
Sixty-two years this week, the No. 2 USAF/Northrop X-4 experimental flight research aircraft took to the air for the first time. The flight of the second X-4 prototype originated from and recovered at Muroc Air Force Base, California.
The USAF/Northrop X-4 was an early X-plane designed to explore the flight characteristics of a swept-wing, tailless aircraft in transonic flight. It came into being as a result of recent Air Force studies which indicated that a tailless configuration might alleviate or eliminate instability issues associated with supersonic flight. The X-4’s external configuration was similar to that of the German Me163 Komet and the British De Havilland DH.108 Swallow.
The USAF contracted with the Northrop Aircraft Company in June of 1946 to construct and perform initial flight testing of two (2) X-4 aircraft. Northrop received the sole-source contract principally because of the company’s vast experience with flying-wing aircraft. Notable examples include the N-1M, XP-79B, XP-56 and the fabled B-35 heavy bomber.
The X-4 was a physically small airplane. As such, it received the nickname Bantam. It measured 23.25-feet in length and had a wing span of 26.75-feet. The wing leading edge sweep angle was 40.5-degrees. Gross take-off weight was 7,820 lbs. Power was provided by a pair of Westinghouse J30-WE-9 non-afterburning turbojets. Each powerplant had a sea level thrust rating of a paltry 1,600-lbs.
Due to the absence of a horizontal tail and an associated elevator, the X-4 was configured with wing-mounted elevons (combined elevator and aileron). These surfaces provided both pitch and roll control. The type’s split trailing edge flaps were used for low-speed lift enhancement as well as speed brake control. Aircraft directional control was provided via a standard vertical tail-mounted rudder.
The No. 1 X-4 aircraft (S/N 46-676) first flew on Wednesday, 15 December 1948 at Muroc Air Force Base, California. Northrop test pilot Charles Tucker was at the controls. The X-4’s first mission revealed that the aircraft was slightly unstable in pitch. Moving the center-of-gravity forward by 3-inches corrected this problem on subsequent X-4 flights.
The No. 2 X-4 aircraft (S/N 46-677) took to the skies over Muroc Air Force Base for the first time on Tuesday, 07 June 1949 with Northrop’s Charles Tucker once again doing the honors. The second X-4 prototype’s air worthiness characteristics and handling qualities were found to be entirely satisfactory.
This vehicle was in fact superior to the No. 1 aircraft in several respects. Not the least of which was a better flight instrumentation suite.
A total of 17 pilots flew the X-4. Northrop’s Charles Tucker piloted all 30 of the contractor flights including 10 in the No. 1 ship and 20 in the No. 2 X-4. The remaining 82 flights were all flown in the No. 2 ship by USAF and NACA pilots including such luminaries as Stanley Butchart (NACA), Scott Crossfield (NACA), Pete Everest (USAF), Jack McKay (NACA), Joe Walker (NACA) and Chuck Yeager (USAF).
The X-4 achieved a maximum altitude of 42,300 on Tuesday, 29 May 1951 and a maximum speed of Mach 0.94 on Monday, 22 September 1952. NACA pilot Scott Crossfield, who piloted the most X-4 flights (31), was at the controls in both instances.
The X-4 handled well below Mach 0.87. However, the aircraft exhibited an annoying porpoising in pitch at higher transonic speeds. Nose-down pitch changes also produced a Mach-tuck effect that worsened with increasing Mach number. The X-4 also had a nasty tendency to pitch-up as it approached sonic speed. These issues were all related in one way or another to the type’s unique tailless, swept wing configuration.
The X-4 flight test program officially ended in September of 1953. Of the 112 total flight tests conducted over the program’s 58-month duration, 102 were flown by the No. 2 ship. While the X-4 never flew supersonically, the type’s transonic flight research program revealed that the hoped-for advantages of a tailless aircraft in supersonic flight were specious.
Happily, both X-4 aircraft survived the flight test program intact. X-4 No. 1 (S/N 46-676) is currently on display at the United States Air Force Academy in Colorado Springs, CO. The No. 2 ship can be seen at the National Museum of the United States Air Force located at Wright-Patterson Air Force Base in Dayton, OH.
Forty years ago today, the United States launched the Mariner 9 spacecraft on a mission to Mars. Among other achievements, Mariner 9 would become the first terrestrial spacecraft to orbit another planet other than Earth.
The Mariner Program was a NASA project whose goal was to investigate the planets Mars, Venus and Mercury from space. A total of ten (10) Mariner spacecraft were launched between 1962 and 1973. Seven (7) of these pioneering missions were considered successful. The first interplanetary flyby, the first orbiting of another planet and the first gravity assist maneuver were all accomplished by Mariner spacecraft.
Each Mariner was built around a central bus or housing that was either hexagonal or octagonal in shape. All spacecraft guidance, navigation, propulsion, communication, power and instrumentation systems were contained within or attached to this central bus. Mariner spacecraft were typically configured with a set of four (4) solar panels for power. However, Mariner’s 1, 2 and 10 used just two (2). Cameras were carried by all Mariner space probes with the exception of Mission’s 1, 2 and 5.
Mariner 9 carried a scientific instrumentation package that consisted principally of an imaging system, ultraviolet spectrometer, infrared spectrometer and infrared radiometer. Fully deployed, each pair of solar panels measured 22.6-feet across. These panels provided 800 watts of power at Earth and 500 watts at Mars. Power was stored in a 20-amp-hour nickel-cadmium battery.
Mariner 9 lift-off mass was 2,196 lbs. Propellant useage during the flyout to Mars resulted in a spacecraft mass of 1,232 lbs in Martian orbit. Scientific instrumentation accounted for 139-lbs of the on-rbit mass. Spacecraft propulsion for mid-course corrections and orbital insertion was provided by a 300-lb thrust liquid rocket motor burning monomethyl hydrazine and nitrogen tetroxide. Mariner 9’s 3.28-foot diameter antenna telemetered data back to Earth at rates of 1, 2, 4, 8 or 16 kilobits/second using dual S-band 10 watt and 20 watt transmitters.
Mariner 9 was launched from Cape Canaveral’s LC-36B at 22:23:00 UTC on Sunday, 30 May 1971. An Atlas-Centaur SLV-3C launch vehicle provided the propulsive energy required to climb out of the Earth’s gravity well and send the probe on its way to Mars. It would take Mariner 9 roughly 167 Earth days to travel a distance of 214.85 million nautical miles to the Red Planet.
Mariner 9 entered Mars orbit at 00:18:00 UTC on Sunday, 14 November 1971. This marked the first time that a terrestrial spacecraft had achieved orbit about another planet in our Solar System other than Earth. Initial orbital parameters included an apoapsis of 9,672-nm and a periapsis of 755-nm at an inclination of 64.3 degrees. Interestingly, Mariner 9 arrived ahead of the Soviet Mars 2 space probe despite the latter’s eleven (11) day head start.
A planet-wide dust storm greeted Mariner 9 upon its arrival in Mars orbit. Hence, imaging of the planetary surface did not begin in earnest until late November. However, it was not until mid-January 1972 that the storm had subsided to the point that high quality images could be obtained from orbit.
Mariner 9 ultimately took 7,329 images which covered 100% of the Martian surface. The photos revealed a fascinating planetary topology that featured river beds, craters, extinct volcanoes, mountains and canyons. Mariner 9 discovered Olympus Mons, the largest known extinct volcano in the Solar System. Valles Marineris, a system of Martian canyons measuring 2,170-nm in length, was named after Mariner 9 in tribute to the probe’s significant space exploration accomplishments. Photographed as well were the diminutive Martian moons of Phobos and Deimos.
Upon depletion of its attitude control system propellant supply, Mariner 9’s mission was officially terminated when the spacecraft’s systems were turned-off on Friday, 27 October 1972. Total time spent investigating the Martian environment from orbit was 349-days. Though long silent, the craft remains in orbit around the Red Planet. It is expected to continue to do so through approximately the year 2022.
Forty-seven years ago this month, the No. 1 USAF/North American XB-70A Valkyrie aircraft was officially unveiled to the aviation public in a rollout ceremony conducted at USAF Plant 42 in Palmdale, California. The Great White Bird’s public debut occurred on Thursday, 11 May 1964.
The XB-70A Valkyrie was designed as an intercontinental bomber. Its original mission was to penetrate Soviet airspace and drop nuclear ordinance at Mach 3 and 70,000 feet. However, that mission was cancelled before the type ever flew. It was ultimately relegated to the status of an experimental flight research vehicle.
The XB-70A graced the skies of America between September 1964 and February 1969. It is to this day the largest triple-sonic aircraft ever flown. The aircraft measured 189 feet in length and had wing span of 105 feet. Gross weight topped out at around 540,000 lbs. Over half of that weight (290,000 lbs) was JP-6 jet fuel.
The Valkyrie was powered by six (6) General Electric YJ93 all-afterburning turbojets. These engines were designed to operate in continuous afterburner at Mach 3.2 and 95,000 feet. Total sea level thrust of the “6-Pack” was in excess of 185,000 lbs. The YJ93 was a contemporary of the Pratt and Whitney J58 turboramjet which powered the fabled USAF/Lockheed SR-71 Blackbird.
Only a pair of XB-70A airframes were built and flown; Air Vehicle No. 1 (S/N 62-0001) and Air Vehicle No. 2 (S/N 62-207). Together, these aircraft flew 129 flight tests totaling 252.6 flight hours. Ship No. 1 flew two-thirds of the XB-70A flight tests. The highest Mach number achieved during the XB-70A flight test program was Mach 3.08. This feat was accomplished by Ship No. 2 on Tuesday, 12 April 1966.
XB-70A Ship No. 2 also achieved the highest altitude of the XB-70A Program. Specifically, this aircraft attained a cruise altitude of 74,000 feet on Saturday, 19 March 1966. This mission included 32 minutes of continuous Mach 3 flight.
Eight (8) men flew the XB-70A. This line-up included Alvin S. White and Van H. Shepard of North American, Col Joseph E. Cotton, Lt Col Fitzhugh L. Fulton, Lt Col Emil (Ted) Sturnthal and Maj Carl S. Cross of the United States Air Force, and Joseph A. Walker and Donald L. Mallick of NASA.
The Valkyrie pioneered the use of numerous technologies including exploitation of the NACA Compression Lift Principle, development of honeycomb sandwich structural materials, and use of its fuel as a heat sink. The XB-70A was also used as a testbed for sonic boom research and a myriad of other aerodynamic and aerothermodynamic experiments. The Valkyrie also provided significant support to the ill-fated American Supersonic Transport (SST) effort.
XB-70A Ship No. 2 was lost in a collision with a NASA F-104N Starfighter near Edwards Air Force Base on Wedneday, 08 June 1966. This mishap took the lives of Maj Carl S. Cross and Joseph A. Walker on what is still referred to as the “Blackest Day at Edwards”. Ship No. 1 survived the XB-70 flight test program and is displayed today at the National Museum of the United States Air Force in Dayton, Ohio.
Forty-nine years ago this month, Mercury Astronaut M. Scott Carpenter orbited the Earth three times aboard his Aurora 7 Mercury spacecraft. In doing so, Carpenter became the second American to reach Earth orbit.
Project Mercury was America’s first manned spaceflight program. A total of six (6) flights took place between May of 1961 and May of 1963. The first two (2) flights were suborbital missions while the remainder achieved low Earth orbits. In February of 1962, John H. Glenn, Jr. became the first American to orbit the Earth during the Mercury-Atlas 6 (MA-6) mission.
Deke Slayton was to fly the Mercury-Atlas 7 (MA-7) mission. However, before that happened, the dreaded flight surgeon cabal grounded Slayton for what they claimed was a heart murmur. Despite Slayton’s utter incredulity and vehement protests, the decision held. Project Mercury officials maintained that the space program could ill afford the negative political fallout occasioned by the death of an astronaut on-orbit.
With Slayton grounded indefinitely, NASA selected Malcom Scott Carpenter to pilot the Mercury-Atlas 7 mission. Carpenter was member of the Original Seven selected by NASA for the Mercury Program in 1959. He was well prepared for the flight since he had just trained as Glenn’s MA-6 backup. As was the practice at that time, Carpenter named his Mercury spacecraft. The appellation he gave his celestial chariot was Aurora 7.
The launch of MA-7 took place on Thursday, 24 May 1962 from LC-14 at Cape Canaveral, Florida. Lift-off time was 12:45:16 UTC. Ascent performance of the stage-and-a-half Atlas D booster was nearly flawless as it inserted Aurora 7 into a 140-nm x 83-nm elliptical orbit. Having been cleared for at least 3 orbits, Carpenter quickly got down to the business of spaceflight.
Much of the activity on the first and second orbits involved Carpenter maneuvering his spacecraft, conducting scientific experiments and observing the Earth from space. Among other discoveries, he discerned that John Glenn’s mysterious “fireflies” were simply particles of ice and frost that had accumulated on the shadow side of the spacecraft. When the spacecraft structure was bumped or vibrated, these particles would disperse from the external surface of the spacecraft and float into space. Once in the strong sunlight, the particles seemed to glow or be luminescent.
A combination of the astronaut’s spacecraft maneuvering and an intermittently malfunctioning pitch horizon scanner left Carpenter with less than half of his maneuvering fuel left at the start of the third and final orbit. Carpenter compensated admirably by barely using his thrusters during Orbit 3. Indeed, nearing the time of retro-fire, Aurora 7 still had 40 percent of his fuel remaining in both the manual and automatic flight control systems.
As retro-fire approached, the intermittent pitch horizon scanner malfunction reappeared at a most inopportune moment. The automatic stabilization and control system suddenly would not hold Aurora 7 in the proper attitude for retro-fire; heatshield 34 degrees above the horizon at zero yaw angle. Carpenter switched to manual mode in an attempt to align the spacecraft properly for retro-fire.
When nominal time for retro-fire came, the retro-rockets did not automatically ignite. Carpenter had to do that manually. But he was 3 seconds late. Worst, Aurora 7 was still yawed 25 degree to the right. And to top it off, retro-thrust was 3 percent low. All of this meant that Aurora 7 would overshoot the nominal landing point by 215 nautical miles.
The trip down through the atmosphere was sporty in that Carpenter ran out of attitude control system fuel early during the descent. This meant that there was no means to propulsively damp the side-to-side oscillations that the Mercury spacecraft normally exhibited during reentry. These oscillations became dangerous when they exceeded about 10 degrees. That is, the spacecraft could tumble end-over-end if left unchecked.
Carpenter simultaneously eyed the altimeter and spacecraft angle-of-attack. As the latter built-up dangerously, his only recourse was to manually fire the drogue earlier than planned in attempt to arrest Aurora 7’s oscillatory motion. He did so at 25,000 feet. The spacecraft’s side-to-side oscillations were stopped. Carpenter then deployed his main parachute at 9,500 feet. Splashdown occurred at 17:41:21 UTC at a point 108 nautical miles northeast of Puerto Rico.
Since Aurora 7 was listing badly and help was about an hour away, Carpenter extricated himself from the spacecraft and deployed his life raft. While a radio beacon helped recovery forces locate him, there was no voice communication between the astronaut and his rescuers. Carpenter was on the water nearly 3 hours before being picked-up by rescue helicopters and delivered to the carrier USS Intrepid. Some six (6) hours later, Aurora 7 was brought onboard the USS John R. Pierce.
Mercury-Atlas 7 was Scott Carpenter’s only space mission. A combination of factors, including less than amicable relations with Mercury Mission Control management, led to this being the case. During the intervening years, many stories alluding to pilot error or inattention as the cause of Aurora 7’s landing overshoot have been circulated. Indeed, much like Gus Grissom’s experience with the loss of his Liberty Bell spacecraft, these stories and explanations have been around long enough that they are now accepted as the “truth”.
Criticism of another’s performance comes easily in this world. However, as Theodore Roosevelt pointed out, it really is “The Man in the Arena” that counts most. In Scott Carpenter’s case, we simply turn the reader’s attention to NASA’s own post-flight report entitled “The Results of the United States Second Manned Orbital Mission”. Among other things, the subject report concluded that the Aurora 7 pilot overcame a “mission critical malfunction” of the pitch horizon scanner and “achieved all mission objectives”. And may we say that in so doing, Scott Carpenter’s MA-7 experience provides yet another validation of the man-in-the-loop concept so critical to the success of manned space operations.
Sixty-one years ago this month, Viking No. 4 soared to a record altitude of 91.2 nautical miles following launch from the USS Norton Sound. Known as Project Reach, the flight was conducted by the United States Navy to demonstrate the feasibility of using ship-launched rockets to carry scientific payloads into space.
The Viking rocket was the first large-scale, liquid-fueled launch vehicle to be developed by the United States. It’s primary mission was to carry scientific instrumentation and research payloads to altitudes as high as 140-nm. As such, the Viking was the domestic follow-on to the V2’s captured from Germany and flown on scientific missions from White Sands Proving Ground (WSPG) in New Mexico.
The Glenn L. Martin developed and built the Viking rocket for the United States Navy. The contract for doing so was let in August of 1946. A total of 12 airframes were built for the Viking Program. The Naval Research Laboratory (NRL) flew 11 of these vehicles between May of 1949 and February of 1955.
There were actually two Viking airframe configurations. The first 7 vehicles measured 47.5 feet in length and had a diameter of 32 inches. Depending on payload and propellant load, gross weight varied between 9,650 and 11,440 lbs. Viking’s 8-12 measured 41.4 feet in length and had a diameter of 45 inches. The average gross weight was 14,796 lbs.
The Viking rocket motor was a product of Reaction Motors Incorporated. It had a sea level thrust rating of 20,000 lbs. As was the case for the V2 rocket powerplant, the Viking’s propellants included alcohol (fuel) and liquid oxygen (oxidizer). Maximum demonstrated rocket motor burn time was 79 seconds for the Viking 1-7 series and 103 seconds for Vikings 8-12. The latter was longer due to the type’s larger propellant capacity.
The Viking’s nominal launch site was White Sands Proving Ground (WSPG) in New Mexico. However, early in the program, the Navy showed great interest in launching the vehicle from a ship at sea. The Navy’s biggest selling point for a shipboard launch was that researchers could choose their launch site. While the service had launched a V-2 from the deck of the USS Midway in 1947, the vehicle went into the drink shortly after lift-off when its control system failed. They hoped to do much better with the Viking.
Project Reach was the official name given to the Navy’s effort to conduct a shipboard launch of a Viking rocket. The USS Norton Sound, a ship that would figure prominently in the history of missile and space testing, was selected as the launch platform. The launch point chosen was the intersection of the Earth’s geographic and geomagnetic equators located near Christmas Island in the Pacific Ocean. The primary payload was a cosmic ray experiment weighing 394 lbs.
Viking No. 4 lifted-off from the deck of the USS Norton Sound at 1608 hours local time on Thursday, 11 May 1950. The vehicle rose straight and true into the partly cloudy tropical sky. Following a 74-second burn and a 168-second coast, the vehicle achieved an apogee of 91.2 nautical miles; the highest a Viking rocket had flown up to that time. Viking No. 4 impacted the ocean within sight of the launch ship about 435 seconds (7.25 minutes) after lift-off. Impact was supersonic.
Viking No. 4 gave the cosmic ray experimenta package a good ride and the data harvest was plentiful. Shipboard launch operations were uneventful in the main and entirely successful. Indeed, the experimentalists, the NRL launch operations team, the USS Norton Sound crew and the United States Navy were pleased with the results of the flight of Viking No. 4. Project Reach was a resounding success.
The Viking Program resumed launches back at WSPG in November of 1950. On Monday, 24 May 1954, Viking 11 reached an altitude of 137 nautical miles. It would be the all-time highest Viking flight.
The rapid pace of space technology during the second half of the 20th century soon caused Viking to fade into history. However, multi-disciplined technology developed during the Viking Program would influence the design and function of numerous subsequent launch vehicles. Perhaps the most direct example being the Navy’s 3-stage Vanguard satellite launch vehicle.
Sixty-four years ago this month, a missile launched on a flight test out of White Sands Proving Ground strayed from the test range and impacted near Ciudad Juarez, Mexico. The non-fatal mishap was attributed to a breakdown in range safety protocol.
The V2 missile (Vengeance Weapon No. 2) was developed by Nazi Germany during World War II for the purpose of attacking Allied population centers. As such, it was the world’s first ballistic missile. History records that more than 3,100 V2’s were fired in anger, with London, England and Antwerp, Belgium being the prime targets. Approximately 7,200 people lost their lives in V2 attacks between September 1944 and March 1945.
The V2 as flown by the Third Reich measured 46 feet in length and had a maximum diameter of 5.4 feet. Launch weight was 28,000 lbs. The V2’s rocket motor produced a maximum thrust of about 60,000 lbs at sea level. Ethyl alcohol and liquid oxygen served as fuel and oxidizer, respectively. Approximately 19,000 pounds of propellants were consumed in 65 seconds of boost flight.
The V2’s payload was an explosive warhead weighing about 1,600 lbs. The fearsome missile’s kinematic performance was impressive for its time. Maximum velocity was around 5,200 ft/sec. After burnout, the rocket followed a ballistic flight path all the way to the target. Maximum altitude and range for wartime missions was on the order of 50 nm and 175 nm, respectively.
With the defeat of Nazi Germany, both the United States and the Soviet Union gained access to a large number of V2 missiles and many of the German rocket scientists who developed the weapon. The United States shipped 300 rail freight cars full of V2 missile components back home. Under Operation Paperclip, some 126 German engineering and scientific personnel were expatriated to the United States. Initially operating out of Fort Bliss, Texas and White Sands Proving Ground (WSPG), New Mexico, these men were destined to make major contributions to the American space program. Among their number was one Werhner von Braun.
Sixty-seven V2 missiles were launched from White Sands Proving Ground (WSPG) between 1946 and 1952. These flights gave the United States invaluable experience in all aspects of rocket assembly, handling, fueling, launching and tracking. Indeed, V2 rocket technology and lessons-learned were applied in the development of all subsequent American launch vehicles ranging from the Redstone to the Saturn V. WSPG V2’s were also used to conduct numerous high altitude and space research experiments. Many aerospace “firsts” were achieved along the way. The first biological space payloads, first photographs of earth from space and the first large two-stage rocket flights involved the former vengeance weapon.
Rocket system reliability was not particularly good in the 1940’s and 1950’s. For instance, only 68% of the WSPG V2 flights were considered successful. Range safety was in its infancy too. In particular, the comprehensive range safety protocol that governs flight operations at today’s test ranges did not yet exist. This state of affairs was largely due to the fact that much of the systems knowledge and operations lessons-learned required to establish such a protocol had yet to be acquired. An incident that occurred in May of 1947 serves to underscore the reliability and safety issues just noted.
The Hermes II missile (RTV-G-3/RV-A-3) was a derivative of the basic V2 vehicle. The payload was a forward-mounted, winged, ramjet engine testbed. The V2’s tail surfaces were enlarged to counter the destabilizing influence of the payload’s wing group. The idea was to get the payload up to a Mach number beyond 3 and separate it from the V2 booster. Following separation, the ramjet pack would be ignited and thrust established. The payload would then fly a programmed altitude-Mach number flight profile. While ambitious on several levels, the project was certainly emblematic of this era of aerospace history wherein all manner of ideas took to the skies.
On Thursday, 29 May 1947, Hermes II was fired from Launch Complex 33 at White Sands Proving Ground. It was approximately 1930 hours local time. It is noted that the ramjet pack was not active for this first flight. The Hermes test vehicle was supposed to pitch to the north and fly uprange. Instead, it pitched to the south and backrange toward El Paso, Texas. Post-flight analysis revealed that the new inertial guidance system employed by the Hermes missile had been wired backwards! This human error directly and adversely affected rocket system reliability.
The WSPG Range Safety Officer(RSO) had both the authority and responsibility to hit the destruct button once it was obvious that the Hermes II was errant. However, a project scientist physically restrained the RSO from doing so! Apparently, the scientist was of the (evidently strong) opinion that the test vehicle’s propellant load should not be wasted on such trivial grounds as the safety of the El Paso populace. Unimpeded now, the errant rocket continued its flight. Range safety protocol would have to be improved and understood by all participants prior to the next flight!
The Hermes II reached a maximum altitude of 35 nm on its unplanned trip to the south. During its 5 -minute flight, the vehicle overflew the city of El Paso and impacted near the Tepeyac Cemetary located 3.5 miles south of Ciudad Juarez, Mexico. The quasi-Mach 1 impact formed a crater that measured 50 feet in width and 24 feet in depth. Enterprising local residents gathered what little airframe wreckage that survived impact and sold it to souvenir seekers!
United States Army authorities quickly arrived on scene to ascertain the extent of the damage caused by the errant missile’s unannounced and unwelcome arrival. Happily, no lives were lost. Profuse apologies were delivered to and graciously accepted by Mexican government officials. The United States paid for all damages and effected a complete clean-up and remediation of the impact site.
A member of the team of expatriated German scientists who conducted the Hermes II flight test later was quoted as saying: “We were the first German unit to not only infiltrate the United States, but to attack Mexico from US soil!” Not nearly so amused, the Army tightened-up range safety protocol at WSPG in the aftermath of the international incident. Interestingly, historical evidence points to the likelihood that the Hermes II vehicle never did carry an active ramjet payload on test flights out of WSPG.
Forty-nine years ago this week, the highly-classified CIA/Lockheed A-12, with Lockheed Test Pilot Lou Schalk at the controls, took to the air for the first time. The historic flight originated from the U.S. government’s top secret flight test facility at Groom Lake, Nevada.
The high stakes of the Cold War compelled the United States to develop the capability to perform covert surveillance missions via overflight of the Soviet Union. The Central Intelligence Agency (CIA) was tasked by the Eisenhower Administration for the job. The CIA partnered with the Lockheed Company to develop a high-flying reconnaissance aircraft known as the U-2.
Outfitted with a suite of high tech cameras and sensors, the U-2 was flown by CIA pilots from 1956 through 1960 to gather vital intelligence data regarding Soviet military capabilities. The aircraft penetrated Soviet territory at altitudes in excess of 70,000 feet and a top speed of about 500 mph. The type’s unrefueled range was more than 5,500 nautical miles. Maximum endurance was 12 hours.
Soon after the U-2 began flying operational missions over the Soviet Union, the U-2 was detected on Soviet radar. Fortunately, Soviet ground-launched missiles were unable to reach the high-flying surveillance aircraft. But the writing was on the wall. It would be only a matter of time before the Soviets improved their defenses to the point that the U-2 would be intercepted. That day occurred on Sunday, 01 May 1960 when a U-2 flown by the CIA’s Francis Gary Powers was brought down over Russia by a Soviet SA-2 missile.
Three years prior to the U-2 incident, the CIA-Lockheed team had begun classified development of the next generation surveillance aircraft. The new aircraft was designed to enter denied airspace at altitudes beyond 85,000 feet and speeds in excess of 2,000 mph (Mach 3+). The camera and sensor systems payload would be a vastly improved over that of the U-2 as well. The idea was to fly when and where required as national security needs dictated.
The CIA’s new supersonic surveillance aircraft was known simply as the A-12. The “A” designation was shorthand for the name Archangel within the Lockheed Advanced Development Projects (The Skunk Works) organization in Burbank, California. The “12” represented the 12th and final iteration of the Archangel airframe design series. In January of 1960, the CIA contracted with Lockheed to produce a dozen A-12’s at the latter’s Burbank facility under the code-name of Project OXCART.
Groom Lake airfield, situated on the USAF’s Area 51 military installation in southern Nevada, was selected as the location for A-12 flight test. The remote and then-publicly-unknown test site was chosen to provide maximum protection from prying eyes and thus help maintain the covert nature of the A-12’s development.
The No. 1 A-12 (S/N 60-6924) was scheduled for what was to be a high-speed taxi test on Saturday, 26 April 1962. The official test plan called for Lockheed Chief Test Pilot Louis W. “Lou” Schalk to get the aircraft up to something just below the minimum rotation velocity of the airplane. However, the A-12’s chief architect, the inimitable Kelly Johnson, privately instructed Schalk to fly the aircraft off the runway and then quickly set it back down. Johnson wanted Schalk to experience how the aircraft felt during take-off in preparation for the upcoming official first flight.
Schalk did as he was instructed. However, as the aircraft took to the air, the pilot found it to be unstable in all three axes. After a pulse-elevating struggle with his shaky stead, Schalk managed to get the A-12 back on the ground in one piece. However, his wild nap-of-the-earth flight profile had consumed 8,000 feet of concrete runway and an additional mile or more of dry lakebed. All that on-lookers could see was a big dust cloud!
Fearing the worst, Groom tower attempted to contact Schalk to ascertain his immediate status. Shalk replied that he and his ship were OK, but the tower never heard his response. The pilot was finally able to turn the A-12 around and taxi back to the hangar area. The Lockheed test team knew that there was plenty to understand and do before the aircraft would be permitted to make its first flight!
Analysis showed that the aircraft (1) did not have its aerodynamic dampers switched to the ON position and (2) center-of-gravity (CG) was located significantly behind the aft CG limit. The former because most pilots would not engage dampers during the early stages of flight test of a new airplane. The latter because the fueling crew, expecting only a runway-hugging high-speed taxi test, had conveniently put most of the gas in the back of the airplane.
The No. 1 A-12 officially made its first flight on Wednesday, 30 April 1962. Take-off and recovery occurred at Groom Lake. The A-12 first achieved supersonic flight the next month. Following a brief, but intense, flight test program, the type entered the USAF operational inventory in 1963. The A-12 retired from active service in June of 1968. By that time, another triple-sonic aircraft had sprung from its loins. That aircraft was none other than the legendary SR-71 Blackbird.
Thirteen A-12 aircraft would ultimately be manufactured by Lockheed. Five of these aircraft were lost over the course of the type’s flying career. Remarkably, A-12 No.1 (S/N 60-6924) survived. In tribute, Lou Schalk’s A-12 first flight beauty is prominently displayed at Blackbird Airpark in Palmdale, California.
Fifty-four years ago this month, the USAF/Ryan X-13 Vertijet completed history’s first vertical-to horizontal-back to vertical flight of a jet-powered Vertical Take-Off and Landing (VTOL) aircraft. This event took place at Edwards Air Force Base, California with Ryan Chief Test Pilot Peter F. Girard at the controls.
The X-13 Vertijet was an experimental flight vehicle designed to determine the feasibility of a jet-powered Vertical Take-Off and Landing (VTOL) aircraft. The initial idea for the type dates back to 1947 when the United States Navy (USN) put Ryan under contract to explore the viability of a jet-powered VTOL aircraft. At the time, the Navy was quite interested in exploiting the VTOL concept for tactical advantage. The service envisioned basing VTOL aircraft on submarines and small surface ships.
The USN-Ryan team worked the X-13 VTOL concept for over six (6) years to good effect. While no flight vehicle took to the skies during that time, a great deal of progress was made in the realm of hovering flight using ground-based vertical test rigs. Particular effort was focused on VTOL low-speed flight controls. However, Navy research and development funding was slashed in the aftermath of the Korean War and the X-13 project ran out of money in the summer of 1953.
Fortunately, the United States Air Force (USAF) had become interested in the X-13 and the possibilities of VTOL flight prior to the Navy running out of money. The junior service assumed ownership of the X-13 effort after securing the funding required to continue the program. A pair of X-13 prototypes were subseqently built and flown by Ryan Aeronautical. These aircraft were assigned USAF serial numbers 54-1619 and 54-1620, respectively.
The X-13 measured 23.5 feet in length and had a wing span of 21 feet. The single-place aircraft featured a maximum take-off weight of approximately 7,300 pounds. Hovering flight control was provided via wing tip-mounted yaw and roll nozzles. The heart of the VTOL aircraft was its reliable Rolls-Royce Avon turbojet. The non-afterburning powerplant used standard JP-4 fuel and produced a maximum thrust of 10,000 pounds.
The X-13 was transported, launched and retrieved using a special flatbed trailer. Hinged at one end, the trailer was raised and lowered through the instrumentality of a pair of hydraulic rams. Once raised to a vertical position, the X-13 hung on its nose hook from a steel suspension cable stretched between two mechanical arms. Rather than landing gear, the aircraft sat on two non-retractable tubular bumpers positioned on the lower fuselage.
Flight testing of the No. 1 X-13 (S/N 54-1619) began on Saturday, 10 December 1955 at Edwards Air Force Base, California. The purpose of this initial flight was to test the X-13’s conventional flight characteristics. The aircraft was configured with tricycle landing to permit a runway take-off. Ryan Chief Test Pilot Peter F. “Pete” Girard flew a brief seven minute test hop in which he determined that the X-13 had serious control issues in all 3-axes. The subsequent installation of yaw and roll dampers fixed the problem.
The next phase of flight testing involved vertical hovering flight wherein aircraft handling and control characteristics were explored. For doing so, the X-13 was outfitted with a vertical landing gear system composed of a tubular support structure and a quartet of small caster-type wheels. Thus configured, the X-13 could take-off, hover and land in the vertical. As vertical flight testing progresed, important refinements were made to the aircraft’s turbojet throttling and reaction control systems.
The first vertical flight test was made on Monday, 28 May 1956 with the No. 1 aircraft. Pete Girard was again in the cockpit. Restricting maximum altitude to about 50 feet above ground level, Girard found the aircraft relatively easy to fly and land. Succeeding flight tests would ultimately include practice hook landings wherein a 1-inch thick manila rope suspended between a pair of 50-foot towers was engaged. A great deal of experience with and confidence in the X-13 system was accrued during these tests.
Prior to flying the X-13 all-up mission, an additional phase of flight testing was required which would culminate with the events of Monday, 28 November 1956. With the conventional landing gear installed on the No. 1 aircraft, Girard took-off from Edwards and climbed to 6,000 feet. He then slowly pitched the aircraft into the vertical and hovered for an extended period. Girard then executed a transition back to horizontal flight and landed. The first-ever horizontal-to vertical-back to horizontal flight transition was entirely successful.
The big day came on Thursday, 11 April 1957. Edwards Air Force Base again served as the test site. This time using the No. 2 X-13 (S/N 54-1620), Pete Girard took-off vertically, ascended in hovering flight and transitioned to conventional flight. Following a series of standard flight maneuevers, Girard transitioned the aircraft back into a vertical hover, descended and engaged the suspension cable on the support trailer with the aircraft’s nose hook. The first-ever vertical-to horizontal-back to vertical flight of a jet-propelled VTOL aircraft was history.
Both X-13 aircraft would go on to successfully conduct additional flight testing and stage numerous flight demonstrations during the remainder of 1957. However, innovative and impressive as it was, the X-13 did not garner the advocacy and backing required to proceed to production. A combination of bad timing, a risk averse military and combat performance limitations resulted in the aircraft and its technology quickly fading from the aviation scene.
Remarkably, both X-13 aircraft survived the type’s flight test program. The No. 1 aircraft (S/N 54-1619) is displayed at the San Diego Aerospace Museum in San Diego, California. The No. 2 X-13 aircraft (S/N 54-1620) is on display in the Annex section of the United States Air Force Museum at Wright-Patterson Air Force Base in Dayton, Ohio.
Forty-one years ago today, the crew of Apollo 13 left Earth headed for the Fra Mauro highlands of the Moon. Less than six days later, they would be back on Earth following an epic life and death struggle to survive the effects of an explosion that rocked their spacecraft 200,000 miles from home.
Apollo 13 was slated as the 3rd lunar landing mission of the Apollo Program. The intended landing site was the mountainous Fra Mauro region near the lunar equator. The Apollo 13 crew consisted of Commander James A. Lovell, Jr., Lunar Module Pilot Fred W. Haise, Jr. and Command Module Pilot John L. (Jack) Swigert, Jr. Lovell was making his fourth spaceflight (second to the Moon) while Haise and Swigert were space rookies.
Apollo 13 lifted-off from LC-39A at Cape Canaveral, Florida on Saturday, 11 April 1970. The official launch time was 19:13:00 UTC (13:13 CST). During second stage burn, the center engine shutdown two minutes early as a result of excessive longitudinal structural vibrations. The outer four J-2 engines burned 34 seconds longer to compensate. Arriving safely in low Earth orbit, Lovell observed that every mission seemed to have at least one major glitch. Clearly, Apollo 13’s was now out of the way!
The Apollo 13 payload stack consisted of a Command Module (CM), Service Module (SM) and Lunar Module (LM). The entire ensemble had a lift-off mass of nearly 49 tons. In keeping with tradition, the Apollo 13 crew gave call signs to their Command Module and Lunar Modules. This helped flight controllers distinguish one vehicle from the other over the communications net during mission operations. The CM was named Odyssey and the LM was given the name of Aquarius.
The first two days of the outward journey to the Moon were uneventful. In fact, some at Mission Control in Houston, Texas seemed somewhat bored. The same could be said for the ever-astute press corps who predictably reported that Americans were now responding to the lunar landing missions with a collective yawn. The journalistic sages averred that the space program needed some pepping-up. Going to the Moon might have been impossible yesterday, but today its just run-of-the-mill stuff. Actually, it was all kind of easy. So wrote they of the fickle Fourth Estate.
It all started with a bang at 03:07:53 UTC on Tuesday, 14 April 1970 (21:07:53 CST, 13 April 1970) with Apollo 13 distanced 200,000 miles from Earth. “Houston, we’ve had a problem here.” This terse statement from Jack Swigert informed Mission Control that something ominous had just occurred onboard Apollo 13. Jim Lovell reported that the problem was a “Main B Bus undervolt”. A potentially serious electrical system problem.
But what was the exact nature of the of problem and why did it occur? Nary a soul in the spacecraft nor in Mission Control could provide the answers. All anyone really knew at the moment was that two of three fuel cells formerly supplying electricity to the Command Module were now dead. Arguably more alarming, Oxygen Tank No. 2 was empty with Tank No. 1 losing oxygen at a high rate.
There was something else. The Apollo 13 reaction control system was firing in apparent response to some perturbing influence. But what was it? The answer came with all the subtleness of a sledge hammer blow. Jim Lovell reported that some kind of gas was venting from the spacecraft into space. That chilling observation suddenly explained why the No. 1 oxygen tank was losing pressure so rapidly.
Once Mission Control and the Apollo 13 astronauts fully comprehended the gravity of the situation, the entire team went to work to bring the spacecraft home. Odyssey was powered-down to conserve its battery power for reentry while Aquarius was powered-up and became a makeshift lifeboat. A major problem was that Aquarius had battery power and water sufficient for only 40 hours of flight. The trip home would take 90 hours.
Amazingly, engineering teams at Mission Control conceived and tested means to minimize electrical useage on Aquarius. However, the Apollo 13 crew would have to endure privation and hardships to survive. The cabin temperature in Aquarius got down to 38F and each man was permitted only six ounces of water per day. The walls of the spacecraft were covered with condensation. Sleep was almost impossible and fatigue became another lingering enemy to survival.
And then there was the build-up of carbon dioxide. The LM environmental system (EV) was designed to support two men. Now there were three. Between the CM and LM, there was an ample supply of lithium hydroxide canisters to scrub the gas from the cabin atmosphere for the trip home. However, the square CM canisters were incompatible with the circular openings on LM EV. The engineers on the ground invented a device to eliminate this compatibility using materials found onboard the spacecraft.
The Apollo 13 crew had to fire the LM descent motor several times in order to adjust their return trajectory. Use of the SM propulsion system to effect these firings was denied the crew due to concerns that the explosion could have damaged it. These rocket motor firings required precise inertial navigation. The star sightings required for celestial navigation were impossible to make owing to the hugh cloud of debris surrounding the spacecraft. Means were devised to use the Sun as the primary navigational source.
As the nation and indeed the world looked on, the miracle of Apollo 13 slowly unfolded. Many a humble heart uttered a prayer for and in behalf of the trio of astronauts. Millions throughout the world followed the men’s journey home via newspaper, radio, televison and other media.
As Apollo 13 approached the Earth, the overriding issue was whether the systems onboard Odyssey could be successfully brought back on line. The walls and instrument panels of the craft were drenched with condensation. Unquestionably, the electronics and wiring bundles behind those instrument panels were also soaking wet. Would they short-out once electrical energy flowed through them again? Would there be enough battery power for reentry?
Happily, the CM power-up sequence was successfully accomplished. Once again the resourceful engineers at Mission Control produced under extreme duress. They devised an intricate and never-attempted-in-flight power-up sequence for the CM. Too, the extra insulation added to the CM’s electrical system in the aftermath of the Apollo 1 fire provided protection from condensation-induced electrical arcing.
Approximately four hours prior to reentry, the Apollo 13 crew jettisoned the SM. What they saw was shocking. The module was missing a complete external panel and most of the equipment inside was gone or significantly damaged. One hour prior to entry, Aquarius, their trusty space lifeboat, was also jettsioned. The only concern now was whether the CM base heatshield had survived the explosion intact.
On Friday, 17 April 1970, Odyssey hit entry interface (400,000 feet) at 36,000 feet per second. Other than a worrisome additional 33 seconds of plasma-induced communications blackout (4 minutes, 33 seconds total), the reentry was entirely nominal. Splashdown occurred at 18:07:41 UTC near American Samoa in the Pacific Ocean. The USS Iwo Jima quickly recovered spacecraft and crew.
The post-flight mishap investigation revealed that Oxygen Tank No. 2 exploded when the crew conducted a cryo-stir of its multi-phase contents. Unkown to all was the fact that a mismatch between the tank heater and thermostat had resulted in the Teflon insulation of the internal wiring being severely damaged during previous ground operations. This meant that the tank was now a bomb and would detonate its contents when used the next time. In this case, the next time was in flight. The warning signs were there, but went unheeded.
Apollo 13 never landed at Fra Mauro. And none of its crew would ever again fly in space. But in many ways, Apollo 13 was NASA’s finest hour. Overcoming myriad seemingly intractable obstacles in the aftermath of a completely unanticipated catastrophe, deep in translunar space, will forever rank high among the legendary accomplishments of flight. With essentially no margin for error and in the harsh glare of public scrutiny, NASA wrested victory from the tenacles of almost certain failure and brought three weary men safely back to their home planet.
Twenty-seven years ago this week, the Solar Max satellite was retrieved from, repaired in and redeployed to orbit by the crew of STS 41-C. The historic event marked the first time in the annals of spaceflight that a satellite was repaired on-orbit.
Space Transportation System (STS) 41-C was one of the most eventful and historic missions of the Space Shuttle Program. The first Shuttle direct ascent was flown, a crippled satellite was repaired in orbit for the first time, a major space research facility was deployed and the famed IMAX camera was first used in space.
STS 41-C was the 11th Space Shuttle mission and the 5th flown by the Challenger orbiter. Mission Commander for STS 41-C was Robert L. Crippen, who was making his 3rd Shuttle flight. The other crew members were space rookies. They included Francis R. “Dick” Scobee, Pilot and Mission Specialists George D. “Pinkie” Nelson, James D. A. “Ox” van Hoften and Terry J. Hart.
STS 41-C was launched from LC-39A at Cape Canaveral, Florida on Friday, 06 April 1984. Lift-off time was 13:58 UTC. The direct ascent profile initially placed the Challenger in a 288-nm circular orbit. The Orbiter’s lift-off mass of 254,254 lbs included 57,279 lbs of payload.
After raising Challenger’s orbit to 313-nm, the STS 41-C crew performed a rendezvous with the malfunctioning Solar Maximum satellite on the third day of the mission. Using the newly-developed Manned Maneuvering Unit (MMU), Mission Specialist Nelson flew out to meet Solar Max which was stationed about 200 feet from the Orbiter. His intent was to grapple it and bring it back into the Challenger payload bay for repairs.
Nelson was equipped with a tool called the Trunnion Pin Acquisition Device (TPAD) for grappling the satellite. Three attempts using the TPAD failed. Apparently, ground-based drawings of the Solar Max grappling pin did not show a grommet that was installed on the actual flight hardware. This prevented the TPAD from working correctly.
When it became evdient that the TPAD would not work, Nelson attempted to grab Solar Max by hand. Unfortunately, this made matters worse as the satellite began tumbling about all three (3) axes. Nelson retired to the Orbiter and Shuttle Mission Control in Houston, Texas went to work on assessing the crew’s next move.
Overnight, Solar Max controllers at Goddard Space Flight Center in Greenbelt, Maryland managed to regain control of the tumbling satellite. In concert with this effort, Shuttle Mission Control in Houston came up with a revised plan to capture Solar Max and dock it in Challenger’s payload bay. The idea now was to grapple the satellite using the Orbiter’s Remote Manipulator System (RMS).
On the fourth day of flight, Mission Specialist Hart successfully grappled Solar Max with the RMS and berthed it in the aft part of the Orbiter’s payload bay. Nelson and van Hoften then went to work. In a space walk lasting almost seven (7) hours, the astronauts skillfully changed-out a faulty attitude control system and the electronics box on the satellite’s coronograph.
Solar Max was redeployed to orbit on Day 5 of STS 41-C. Following a 30-day checkout by Goddard flight controllers, the satellite resumed full operation. While certainly more difficult than expected, the Solar Max repair effort was an unqualified success. Following a mission of 6 days, 23 hours, 40 minutes and 7 seconds, Challenger safely landed at Edwards Air Force Base, California on Friday, 13 April 1984.
The Solar Max repair mission of April 1984 set the stage for more challenging and extensive future work in space. Indeed, three (3) successful Hubble Telescope repair and refurbishment missions as well as construction of the International Space Station (ISS) share an important experiential linkage with the pioneering STS 41-C effort.
Seven years ago this week, the NASA X-43A scramjet-powered flight research vehicle reached a record speed of over 4,600 mph (Mach 6.83). The test marked the first time in the annals of aviation that a flight-scale scramjet accelerated an aircraft in the hypersonic Mach number regime.
NASA initiated a technology demonstration program known as HYPER-X in 1996. The fundamental goal of the HYPER-X Program was to successfully demonstrate sustained supersonic combustion and thrust production of a flight-scale scramjet propulsion system at speeds up to Mach 10.
Also known as the HYPER-X Research Vehicle (HXRV), the X-43A aircraft was a scramjet test bed. The aircraft measured 12 feet in length, 5 feet in width, and weighed nearly 3,000 pounds. The X-43A was boosted to scramjet take-over speeds with a modified Orbital Sciences Pegasus rocket booster.
The combined HXRV-Pegasus stack was referred to as the HYPER-X Launch Vehicle (HXLV). Measuring approximately 50 feet in length, the HXLV weighed slightly more than 41,000 pounds. The HXLV was air-launched from a B-52 mothership. Together, the entire assemblage constituted a 3-stage vehicle.
The second flight of the HYPER-X program took place on Saturday, 27 March 2004. The flight originated from Edwards Air Force Base, California. Using Runway 04, NASA’s venerable B-52B (S/N 52-0008) started its take-off roll at approximately 20:40 UTC. The aircraft then headed for the Pacific Ocean launch point located just west of San Nicholas Island.
At 21:59:58 UTC, the HXLV fell away from the B-52B mothership. Following a 5 second free fall, rocket motor ignition occurred and the HXLV initiated a pull-up to start its climb and acceleration to the test window. It took the HXLV about 90 seconds to reach a speed of slightly over Mach 7.
Following rocket motor burnout and a brief coast period, the HXRV (X-43A) successfully separated from the Pegasus booster at 94,069feet and Mach 6.95. The HXRV scramjet was operative by Mach 6.83. Supersonic combustion and thrust production were successfully achieved. Total engine-on duration was approximately 11 seconds.
As the X-43A decelerated along its post-burn descent flight path, the aircraft performed a series of data gathering flight maneuvers. A vast quantity of high-quality aerodynamic and flight control system data were acquired for Mach numbers ranging from hypersonic to transonic. Finally, the X-43A impacted the Pacific Ocean at a point about 450 nautical miles due west of its launch location. Total flight time was approximately 15 minutes.
The HYPER-X Program made history that day in late March 2004. Supersonic combustion and thrust production of an airframe-integrated scramjet were achieved for the first time in flight; a goal that dated back to before the X-15 Program. Along the way, the X-43A established a speed record for airbreathing aircraft and earned a Guinness World Record for its efforts.
Fifty-three years ago this week, Explorer III became the third artificial satellite to be successfully orbited by the United States. Interestingly, this early trio of successful orbital missions had been achieved in a period of less than 60 days.
The early Explorer satellites (Explorer I, II and III) were designated as Explorer A spacecraft. Their primary mission was to study the Earth’s Magnetosphere. Each satellite measured about 81-inches in length and had a maximum diameter of 6.5-inches. On-orbit weight was close to 31 pounds.
Explorer satellite instrumentation was modest. The primary instruments carried included a cosmic ray detector and micrometeorite erosion gauges. Data were transmitted to Earth using a 60 milliwatt dipole antenna transmitter and a 10 milliwatt turnstile transmitter. Electrical power was provided by mercury chemical batteries that accounted for roughly 40 percent of the payload weight.
Explorer I was the first artificial satellite to achieve Earth orbit. The satellite was launched atop a Jupiter-C launch vehicle on Friday, 31 January 1958 from LC-26A at Cape Canaveral, Florida. The country’s first satellite quickly went to work and discovered what we know today as the Van Allen Radiation Belts.
Explorer II was to verify and expand upon the findings of Explorer I. However, the craft never achieved orbit after it was launched on Wednesday, 05 March 1958. The cause was attributed to a failure in the 4th stage of its Jupiter-C launch vehicle. While the outcome was disappointing, the Explorer Program quickly readied another Explorer satellite for flight.
Explorer III was launched from Cape Canaveral’s LC-5 on Wednesday, 26 March 1958 at 17:31 UTC. The Jupiter-C launch vehicle performed admirably and delivered Explorer III into a highly elliptical 1,511-nm x 100-nm orbit. However, all was not well in orbit. Telemetry data indicated that the pencil-like satellite was tumbling at a rate of about 1 cycle every 7 seconds.
Explorer III performed its intended mission in spite of the anomalous tumbling motion. Indeed, the craft corroborated the findings of Explorer I and helped verify the existence of the Van Allen Radiation belts. However, the unwanted tumbling increased Explorer III’s aerodynamic drag and significantly shortened its mission lifetime.
Explorer III’s orbit decayed to the point that it reentered the Earth’s atmosphere on Tuesday, 27 June 1958. During its 93 days in space, the spacecraft made approximately 1,160 trips around the Earth.
Forty-five years ago this week, the crew of Gemini VIII successfully regained control of their tumbling spacecraft following failure of an attitude control thruster. The incident marked the first life-threatening on-orbit emergency and resulting mission abort in the history of Amercian manned spaceflight.
Gemini VIII was the sixth manned mission of the Gemini Program. The primary mission objective was to rendezvous and dock with an orbiting Agena Target Vehicle (ATV). Successful accomplishment of this objective was seen as a vital step in the Nation’s quest for landing men on the Moon.
The Gemini VIII crew consisted of Command Pilot Neil A. Armstrong and Pilot USAF Major David R. Scott. Both were space rookies. To them would go both the honor of achieving the first successful docking in orbit as well as the challenge of dealing with the first life and death space emergency involving an American spacecraft.
Gemini VIII lifted-off from Cape Canaveral’s LC-19 at 16:41:02 UTC on Wednesday, 16 March 1966. The crew’s job was to chase, rendezvous and then physically dock with an Agena that had been launched 101 minutes earlier. The Agena successfully achieved orbit and waited for Gemini VIII in a 161-nm circular Earth orbit.
It took just under six (6) hours for Armstrong and Scott to catch-up and rendezvous with the Agena. The crew then kept station with the target vehicle for a period of about 36 minutes. Having assured themselves that all was well with the Agena, the world’s first successful docking was achieved at a Gemini mission elasped time of 6 hours and 33 minutes.
Once the reality of the historic docking sank in, a delayed cheer erupted from the NASA and contractor team at Mission Control in Houston, Texas. Despite the complex orbital mechanics and delicate timing involved, Armstrong and Scott had made it look easy. Unfortunately, things were about to change with chilling suddeness.
As the Gemini crew maneuvered the Gemini-Agena stack, their instruments indicated that they were in an uncommanded 30-degree roll. Using the Gemini’s Orbital Attiude and Maneuvering System (OAMS), Armstrong was able to arrest the rolling motion. However, once he let off the restoring thruster action, the combined vehicle began rolling again.
The crew’s next action was to turn off the Agena’s systems. The errant motion subsided. Several minutes elapsed with the control problem seemingly solved. Suddenly, the uncommanded motion of the still-docked pair started again. The crew noticed that the Gemini’s OAMS was down to 30% fuel. Could the problem be with the Gemini spacecraft and not the Agena?
The crew jettisoned the Agena. That didn’t help matters. The Gemini was now tumbling end over end at almost one revolution per second. The violent motion made it difficult for the astronauts to focus on the instrument panel. Worse yet, they were in danger of losing consciousness.
Left with no other alternative, Armstrong shut down his OAMS and activated the Reentry Control System reaction control system (RCS) in a desperate attempt to stop the dizzying tumble. The motion began to subside. Finally, Armstrong was able to bring the spacecraft under control.
That was the good news. The bad news for the crew of Gemini VIII was that the rest of the mission would now have to be aborted. Mission rules dictated that such would be the case if the RCS was activated on-orbit. There had to be enough fuel left for reentry and Gemini VIII had just enough to get back home safely.
Gemini VIII splashed-down in the Pacific Ocean 4,320 nm east of Okinawa. Mission elapsed time was 10 hours, 41 minutes and 26 seconds. Spacecraft and crew were safely recovered by the USS Leonard F. Mason.
In the aftermath of Gemini VIII, it was discovered that OAMS Thruster No. 8 had failed in the ON position. The probable cause was an electrical short. In addition, the design of the OAMS was such that even when a thruster was switched off, power could still flow to it. That design oversight was fixed so that subsequent Gemini missions would not be threatened by a reoccurence of the Gemini VIII anomaly.
Neil Armstrong and David Scott met their goliath in orbit and defeated the beast. Armstrong received a quality increase for his efforts on Gemini VIII while Scott was promoted to Lieutenant Colonel. Both men were awared the NASA Exceptional Service Medal.
More significantly, their deft handling of the Gemini VIII emergency elevated both Armstrong and Scott within the ranks of the astronaut corps. Indeed, each man would ultimately land on the Moon and serve as mission commander in doing so; Neil Armstrong on Apollo 11 and David Scott on Apollo 15.
Forty-nine years ago today, the United States successfully launched Orbiting Solar Observatory No. 1 (OSO-1) into Earth orbit. This robotic spacecraft provided the first detailed scientific examination of the Sun from space.
The 1960’s was a time of both rapid growth and spectacular achievements in space exploration. Indeed, weather satellites, communications satellites and surveillance satellites were new inventions. Robotic space probes were sent to orbit and land on the Moon. Other autonomous spacecraft visited the inner planets of the Solar System. Men orbited the Earth. Still others landed on and returned from the Moon.
Space probes were also employed to good effect in an effort to learn more about our Sun. NASA’s Orbiting Solar Observatory (OSO) Program was America’s first attempt to acquire detailed solar physics data using orbital spacecraft. A total of eight (8) OSO space probes were launched into Earth orbit between 1962 and 1975.
The fundamental objective of the OSO Program was to monitor and measure solar electromagnetic radiation levels over an 11-year sun spot cycle. The idea was to map the direction and intensity of Ultraviolet, X-Ray and Gamma radiation throughout the celestial sphere over the long solar cycle. Onboard scientific instrumentation included a solar spectrometer, scintillation detector, proton electron analyzer and various flux monitors
OSO satellites were relatively large and complex for their time. Spacecraft attitude had to be tightly controlled since onboard instrument systems needed to be continuously trained on the solar disk. The probe’s solar physics data could be transmitted to ground receiving stations in real-time or recorded on tape for later transmittal.
OSO-1 was the first solar observatory orbited by the United States. Launch from Cape Canaveral’s LC-17A took place on Wednesday, 07 March 1962 at 16:04:00 UTC. A Thor-Delta 301/D8 launch vehicle placed the 458-lb OSO-1 satellite into a near circular Earth orbit (291-nm x 275-nm). The orbital period of 94.7 minutes meant that OSO-1 orbited the Earth 15.2 times each day.
OSO-1 performed well until its second onboard tape recorder gave up the ghost. This anomaly occurred on Tuesday, 15 May 1962. The loss of its last functional data recorder meant that all subsequent measurements had to be transmitted in real-time.
OSO-1 would continue making and transmitting solar physics measurements until May of 1964. At that time, the spacecraft power supply died when its solar cells failed. Although dormant, OSO-1 would continue to orbit the Earth for another seventeen (17) years. The spacecraft reentered the Earth’s atmosphere on Thursday, 08 October 1981.
OSO-1 and all succeeding OSO satellites contributed significantly to progress in the realm of solar physics. The OSO Program laid the foundation for more sophisticated and detailed study of our Sun through the auspices of such solar probes as SOHO, Ulysses and Skylab. Indeed, NASA’s Solar Probe Plus probe, currently scheduled to fly within the Sun’s coronal region sometime in the 2015/2016 period, will continue the legacy begun long ago by OSO-1.
Fifty-five years ago this month, the USAF/North American X-10 experimental research vehicle hit a maximum speed of Mach 2.05 during its 19th test flight. The mark established a new speed record for turbojet-powered aircraft.
The precedent set by the Nazi V-1 and V-2 Vergeltungswaffen (Vengeance Weapons) in World War II motivated the United States to launch a post-war effort to develop a strategic range-capable missile capability. The earliest example in this regard was the USAF/North American Navaho (SM-64).
Known as Project MX-770, the Navaho was developmental effort to deliver a nuclear warhead at a range of 5,500 nm. The Navaho configuration consisted of a rocket-powered first stage and a winged second stage utilizing ramjet propulsion. The second stage was designed to cruise at Mach 2.75.
The X-10 was a testbed version of the Navaho second stage. The X-10 measured 66 feet in length, sported a wingspan of 28 feet and had a GTOW of 42,000 lbs. The sleek aircraft was powered by twin Westinghouse J40-WE-1 turbojets. These powerplants burned JP-4 and were each rated at 10,900 lbs of sea level thrust in full afterburner.
The X-10 was a double sonic-capable aircraft. It had an unrefueled range of 850 miles and a maximum altitude capability of 44,800 feet.
The X-10 vehicle flight surfaces included elevons for pitch and roll control and twin rudders for yaw control. Canard surfaces were employed for pitch trim. The aircraft was designed to take-off, maneuver and land under external control provided by either airborne or ground-based assets.
A total of thirteen (13) X-10 airframes were constructed by North American. Flight testing originated at the Air Force Flight Test Center (AFFTC), Edwards Air Force Base, California and later moved to the Air Force Missile Test Center (AFMTC) at Cape Canaveral in Florida.
There was a total of twenty-seven (27) X-10 flight tests. Fifthteen (15) flight tests took place at the AFFTC between October of 1953 and March of 1955. Twelve (12) flight tests were conducted at the AFMTC between August 1955 and November 1956.
X-10 airframe GM-52-1 achieved the highest speed of the type’s flight test series. On Wednesday, 29 February 1956, the aircraft recorded a peak Mach Number of 2.05 during the 19th flight test of the X-10 Program. At the time, this was a record for turbojet-powered aircraft. The mission originated from and recovered to the AFMTC.
While the X-10 Program produced a wealth of aerodynamic, structural, flight control and flight performance data, test vehicle attrition was extremely high. The lone X-10 to survive flight testing was airframe GM-19307. It is currently on display at the Museum of the United States Air Force at Wright-Patterson Air Force Base in Dayton, Ohio.
Fifty-six years ago this week, North American test pilot George F. Smith became the first man to survive ejection from an aircraft in supersonic flight. Smith ejected from his F-100A Super Sabre at 777 MPH (Mach 1.05) as the crippled aircraft passed through 6,500 feet in a near-vertical dive.
On the morning of Saturday, 26 February 1955, North American Aviation (NAA) test pilot George F. Smith stopped by the company’s plant at Los Angeles International Airport to submit some test reports. Returning to his car, he was abruptly hailed by the company dispatcher. A brand-new F-100A Super Sabre needed to be test flown prior to its delivery to the Air Force. Would Mr. Smith mind doing the honors?
Replying in the affirmative, Smith quickly donned a company flight suit over his street clothes, got the rest of his flight gear and pre-flighted the F-100A Super Sabre (S/N 53-1659). After strapping into the big jet, Smith went through the normal sequence of aircraft flight control and system checks. While the control column did seem a bit stiff in pitch, Smith nonetheless made the determination that his steed was ready for flight.
Smith executed a full afterburner take-off to the west. The fleet Super Sabre eagerly took to the air. Accelerating and climbing, the aircraft was almost supersonic as it passed through 35,000 feet. Peaking out around 37,000 feet, Smith sensed a heaviness in the flight control column. Something wasn’t quite right. The jet was decidely nose heavy. Smith countered by pulling aft stick.
The Super Sabre did not respond at all to Smith’s control inputs. Instead, it continued an uncommanded dive. Shallow at first, the dive steepened even as the 215-lb pilot pulled back on the stick with all of his might. But all to no avail. The jet’s hydraulic system had failed. As the stricken aircraft now accelerated toward the ground, Smith rightly concluded that this was going to be a short ride.
George Smith knew that he had only one alternative now. Eject. However, he also knew that the chances were small that he could survive what was quickly shaping-up to be a quasi-supersonic ejection. Suddenly, over the radio, Smith heard another F-100A pilot flying in his vicinity yell: “Bail out, George! He proceeded to do so.
Smith jettisoned his canopy. The roar from the airstream around him was unlike anything he had ever heard. Almost paralyzed with fear, Smith reflexively hunkered-down in the cockpit. The exact wrong thing to do. His head needed to be positioned up against the seat’s headrest and his feet placed within retraining stirrups prior to ejection. But there was no time for any of this now. Smith pulled the ejection seat trigger.
George Smith’s last recollection of his nightmare ride was that the Mach Meter read 1.05; 777 mph at the ejection altitude of 6,500 feet above the Pacific Ocean. These flight conditions corresponded to a dynamic pressure of 1,240 pounds per square foot. As he was fired out of the cockpit and into the harsh airstream, Smith was subjected to a drag force of around 8,000 lbs producing on the order of 40-g’s of deceleration.
Mercifully, Smith did not recall what came next. The ferocious windblast stripped him of his helmet, oxygen mask, footwear, flight gloves, wrist watch and even his ring. Blood was forced into his head which became grotesquely swollen and his facial features unrecognizable. His eyelids fluttered and his eyes were tortuously mauled by the aerodynamic and inertial load of his ejection. Smith’s internal organs, most especially his liver, were severely damaged. His body was horribly bruised and beaten as it flailed end-over-over end uncontrollably.
Smith and his seat parted company as programmed followed by automatic deployment of his parachute. The opening forces were so high that a third of the parachute material was ripped away. Thankfully, the remaining portion held together and the unconscious Smith landed about 75 yards away from a fishing vessel positiond about a half-mile form shore. Providentially, the boat’s skipper was a former Navy rescue expert. Within a minute of hitting the water, Smith was rescued and brought onboard.
George Smith was hovering near death when he arrived at the hospital. In severe shock and with only a faint pulse, doctors quickly went to work. Smith awoke on his sixth day of hospitalization. He could hear, but he couldn’t see. His eyes had sustained multiple subconjunctival hemorrhages and the prevailing thought at the time was that he would never see again.
Happily, George Smith did recover almost fully from his supersonic ejection experience. He spent seven (7) months in the hospital and endured several operations. During that time, Smith’s weight dropped to 150 lbs. He was left with a permanently damaged liver to the extent that he could no longer drink alcohol. As for Smith’s vision, it returned to normal. However, his eyes were ever after somewhat glare-sensitive and slow to adapt to darkness.
Not only did George Smith return to good health, he also got back in the cockpit. First, he was cleared to fly low and slow prop-driven aircraft. Ultimately, he got back into jets, including the F-100A Super Sabre. Much was learned about how to markedly improve high speed ejection survivability in the aftermath of Smith’s supersonic nightmare. He in essence paid the price so that others would fare better in such circumstances as he endured.
George Smith was thirty-one (31) at the time of his F-100A mishap. He lived a happy and productive thirty-nine (39) more years after its occurrence. Smith passed from this earthly scene in 1994.
Fifty-years ago this week, the NASA SCOUT small launch vehicle successfully orbited the Explorer IX satellite. This achievement marked the first time that an all-solid propellant launch vehicle orbited an artificial satellite.
The concept for the Solid Controlled Orbital Utility Test (SCOUT) launch vehicle dates back to the late 1950’s. The National Advisory Committee For Aeronautics (NACA) saw a need to develop a simple, low-cost launch vehicle for boosting small science payloads into space. Propulsion units for each stage would be selected from the existing inventory of solid rocket motors.
In the same time period, the United States Air Force (USAF) was moving toward the development of a small launch vehicle (SLV) to support a variety of suborbital and orbital military missions. The junior service subsequently partnered with the recently established National Aeronautics and Space Administration (NASA) in March of 1959 to develop a “poor man’s rocket.”
The SCOUT SLV was a 4-stage, all-solid propellant launch vehicle that stood roughly 75-feet in height. The initial version of the vehicle was designed to put a 130-lb payload into a 115 nm circular Earth orbit. The payload capacity of later versions approached 500 lbs. A fifth stage could be added to provide greater velocity performance for missions involving reentry vehicle research, highly elliptical orbits and solar probes.
The original SCOUT propulsion stack consisted of an Algol 1st stage (105,000 lbs thrust), Castor 2nd stage (64,300 lbs thrust), Antares 3rd stage (13,500 lbs thrust) and an Altair 4th stage (3,000 lbs thrust). Many variants of the SCOUT were developed over the program’s life time as the demand increased for higher payload capability. These variants were primarily the result of rocket motor thrust-level upgrades.
A compelling aspect of the SCOUT SLV was the fact that its launch support infrastructure was less involved that the bigger liquid-fueled launch vehicles such as Atlas, Delta and Titan. SCOUT was launched from at least three (3) separate sites; Wallops Island, VA, Vandenberg AFB, CA and San Marco Island just off the coast of Kenya. The latter pair of launch locations supported polar and equatorial orbit missions, respectively.
SCOUT developmental test flights began in April of 1960. The first ten (10) test flights included four (4) orbital attempts. The only successful orbital mission was that flown on Thursday, 16 February 1961 with launch taking place from LA-3 at the Wallops Flight Facility (WFF). The Explorer IX payload was successfully placed into orbit where it was used to study the density and composition of the upper thermosphere and lower exosphere. This mission also marked the first time that a satellite had been orbited from WFF.
While NASA’s SCOUT SLV program lasted more than three (3) decades and was very successful, USAF’s experience with the vehicle was quite different. Under the code names Blue SCOUT and Blue SCOUT Junior, the service employed variants of the basic SCOUT SLV for military missions. Hardware reliability issues and inter-organizational disconnects with NASA led to the USAF SCOUT SLV program being ended in 1967.
The NASA SCOUT SLV was flown 116 times between 1960 and 1994. Of that total, the break-out between research and development (R&D) flights and operational missions was 21 and 95, respectively. Parenthetically, it must be noted that the variety of space payloads launched by SCOUT is a story in itself. (One that must be told another day.) Suffice it to say here that SCOUT was a workhorse launch vehicle for NASA and contributed mightily to the scientific exploration of both near and deep space.
Thirty-seven years ago this month, the Mariner 10 interplanetary space probe successfully conducted a flyby encounter with the planet Venus. The Venusian flyby served as a necessary prelude to a subsequent first-ever flyby of the planet Mercury.
The Mariner Program concentrated on the scientific exploration of the inner planets of the solar system. Namely, Mars, Venus and Mercury. A total of ten (10) Mariner missions were attempted; seven (7) of which were successful. These missions were flown between 1962 and 1974. As outlined below, the Mariner Program recorded a number of important spaceflight firsts.
Mariner spacecraft were the first to successfully conduct a flyby of Venus (Mariner 2), Mars (Mariner 4) and Mercury (Mariner 10). Additionally, the first close-up photos of Mars and Venus were taken by Mariner 4 and Mariner 10, respectively. Mariner 9 was the first spacecraft to orbit Mars. Finally, Mariner 10 was the first space probe to fly a gravity assist trajectory and perform a flyby of two (2) planets (Venus and Mercury) during a single mission.
Mariner spacecraft weighed between 450 and 950 lbs for flyby missions and 2,200 lbs for an orbital mission. Each carried a variety of mission-specific sensors including radiometers, spectrometers and television cameras. Atlas-Agena (Mariners 1 to 5) and Atlas-Centaur (Mariners 6 to 10) launch vehicles provided the energy required for Earth-escape.
Mariner 10 was the last mission of the Mariner Program. The primary objectives were to make measurements of the space, atmospheric and surface environments of Venus and Mercury. This dual-planet mission required the first-ever use of a gravity assist maneuver to get to Mercury. In particular, the gravity of Venus would be used to deflect the Mariner 10 trajectory such that it would be able to encounter Mercury.
Mariner 10 was launched from Cape Canaveral’s LC-36B at 05:45 UTC on Saturday, 03 November 1973. It took 94 days for Mariner 10 to arrive at Venus. As a bonus, the space probe trained its complement of sensors on the Comet Kohoutek along the way. On Tuesday, 05 February 1974, Mariner 10 passed within 3,100 nm of the Venusian surface at 17:01 UTC. The spacecraft then sailed on toward its future flyby encounters with Mercury.
Mariner 10 learned many things about Venus. Venus was found to have an atmospheric circulation pattern somewhat like that of Earth. Although its strength is very much less than that of Earth, Venus was found to have a magnetic field. The planet’s ionosphere also interacted with the solar wind to produce a huge bow shock flowfield in the exoatmospheric region surrounding the planet.
Between March of 1974 and March of 1975, Mariner 10 performed three (3) flybys of the planet Mercury. The closest approach to the planet’s surface was a mere 177 nm. Mercury’s surface was found to be very Moon-like in that it is heavily-cratered. Spacecraft measurements also confirmed that Mercury does not have an atmosphere. Further, Mercury was found to have a predominatly iron-laden core as well as a small magnetic field.
Following the last of the trio of flyby encounters with Mercury, Mariner 10 systems were put through a number of engineering tests. The mission was officially brought to an end on Monday, 24 March 1975 when the spacecraft attitude control system propellant supply went to zero. Today, the Mariner 10 hulk continues in an eternal orbit about the Sun.
Fifty-years ago today, NASA successfully conducted a critical flight test of the agency’s Mercury-Redstone vehicle which helped clear the way for the United States’ first manned suborbital spaceflight. Riding the Mercury spacecraft into space and back was a 44-month old chimpanzee by the name of HAM.
Project Mercury was America’s first manned spaceflight program. Simply put, Mercury helped us learn how to fly astronauts in space and return them safely to earth. A total of six (6) manned missions were flown between May of 1961 and May of 1963. The first two (2) flights were suborbital shots while the final four (4) flights were full orbital missions. All were successful.
The Mercury spacecraft weighed about 3,000 lbs, measured 9.5-ft in length and had a base diameter of 6.5-ft. Though diminutive, the vehicle contained all the systems required for manned spaceflight. Primary systems included guidance, navigation and control, environmental control, communications, launch abort, retro package, heatshield, and recovery.
Mercury spacecraft launch vehicles included the Redstone and Atlas missiles. Both were originally developed as weapon systems and therefore had to be man-rated for the Mercury application. Redstone, an Intermediate Range Ballistic Missile (IRBM), was the booster for Mercury suborbital flights. Atlas, an Intercontinental Ballistic Missile (ICBM), was used for orbital missions.
Early Mercury-Redstone (MR) flight tests did not go particularly well. The subject missions, MR-1 and MR-1A, were engineering test and development flight tests flown with the intent of man-rating both the coverted launch vehicle and new spacecraft.
MR-1 hardly flew at all in that its rocket motor shut down just after lift-off. After soaring to the lofty altitude of 4-inches, the vehicle miraculously settled back on the launch pad without toppling over and detonating its full load of propellants. MR-1A flew, but owing to higher-than-predicted acceleration, went much higher and farther than planned. Nonetheless, MR flight testing continued in earnest.
The objectives of MR-2 were to verify (1) that the fixes made to correct MR-1 and MR-1A deficiencies indeed worked and (2) proper operation of a bevy of untested systems as well. These systems included environmental control, attitude stabilization, retro-propulsion, voice communications, closed-loop abort sensing and landing shock attenuation. Moreover, MR-2 would carry a live biological payload (LBP).
A 44-month old male chimpanzee was selected as the LBP. He was named HAM in honor of the Holloman Aerospace Medical Center where the primate trained. HAM was taught to pull several levers in response to external stimuli. He received a banana pellet as a reward for responding properly and a mild electric shock as punishment for incorrect responses. HAM wore a light-weight flight suit and was enclosed within a special biopack during spaceflight.
On Tuesday, 31 January 1961, MR-2 lifted-off from Cape Canaveral’s LC-5 at 16:55 UTC. Within one minute of flight, it became obvious to Mission Control that the Redstone was again overaccelerating. Thus, HAM was going to see higher-than-planned loads at burnout and during reentry. Additionally, his trajectory would take him higher and farther downrange than planned. Nevertheless, HAM kept working at his lever-pulling tasks.
The Redstone burnout velocity was 5,867 mph rather than the expected 4,400 mph. This resulted in an apogee of 137 nm (100 nm planned) and a range of 367 nm (252 nm predicted). HAM endured 14.7 g’s during entry; well above the 12 g’s planned. Total flight duration was 16.5 minutes; several minutes longer than planned.
Chillingly, HAM’s Mercury spacecraft experienced a precipitous drop in cabin pressure from 5.5 psig to 1 psig just after burnout. High flight vibrations had caused the air inlet snorkel valve to open and dump cabin pressure. HAM was both unaware of and unaffected by this anomaly since he was busy pulling levers within the safety of his biopack.
HAM’s Mercury spacecraft splashed-down at 17:12 UTC about 52 nm from the nearest recovery ship. Within 30 minutes, a P2V search aircraft had spotted HAM’s spacecraft (now spaceboat) floating in an upright position. However, by the time rescue helicopters arrived, the Mercury spacecraft was found floating on its side and taking on sea water.
Apparently, a combination of impact damage to the spacecraft’s pressure bulkhead and the open air inlet snorkel valve resulted in HAM’s spacecraft taking on roughly 800 lbs of sea water. Further, heavy ocean wave action had really hammered HAM and the Mercury spacecraft. The latter having had its beryllium heatshield torn away and lost in the process.
Fortunately, one of the Navy rescue helicopters was able to retrieve the waterlogged spacecraft and deposit it safely on the deck of the USS Donner. In short order, HAM was extracted from the Mercury spacecraft. Despite the high stress of the day’s spaceflight and recovery, HAM looked pretty good. For his efforts, HAM received an apple and an orange-half.
While the MR-2 was judged to be a success, one more flight would eventually be flown to verify that the Redstone’s overacceleration problem was fixed. That flight, MR-BD (Mercury-Redstone Booster Development) took place on Friday, 24 March 1961. Forty-two (42) days later USN Commander Alan Bartlett Shepard, Jr. became America’s first astronaut.
MR-2 was HAM’s first and only spaceflight experience. He quietly lived the next 17 years as a resident of the National Zoo in Washington, DC. His last 2 years were spent living at a North Carolina zoo. On Monday, 19 January 1983, HAM passed away at the age of 26. HAM is interred at the New Mexico Museum of Space History in Alamogordo, NM.
Seven years ago this week, NASA’s Mars Exploration Rover (MER) Opportunity landed at Meridiani Planum on the surface of the planet Mars. Incredibly, the robotic rover continues to gather geological, atmospheric and astronomical data well beyond its design mission duration of ninety (90) Martian days.
Mars is the 4th planet out from the Sun. It has a diameter a little more than half that of Earth. The duration of a day on Mars is a little more than that on Earth. However, a Martian year is 88% longer than a terrestrial year. While nebulous in comparison to the Earth, Mars has an atmosphere. Atmospheric temperature ranges from -190F to +98F.
Mars has always been a source of curious speculation by we Earthlings. Does or did Mars ever have water? Does or did Mars ever have life in any form? The quest to answer these and related questions has resulted in significant exploration of the Martian space, atmosphere and surface by robotic space vehicles sent from the Earth.
In 1976, Viking 1 and Viking 2 became the first American spacecraft to land on the surface of Mars. In July of 1997, the Mars Pathfinder became the first successful United States robotic rover. While a spectacular accomplishment, that first rover’s exploration capabilities and science output were modest. Something more substantial was required to provide a quantum leap in our understanding of Mars.
That something was the Mars Exploration Rover (MER) of which there would be two (2) copies. MER-A (Spirit) and MER-B (Opportunity) would be targeted to opposite hemispheres where each rover would investigate Martian geology up-close and personal. Each was configured with a sophisticated suite of scientific equipment for doing so. Together, the rovers were destined to provide the most detailed investigation of Martian geology in history.
Each MER weighs 408 lbs and measures 7.5-feet in width, 4.9-feet in height and 5.2-feet in length. Six (6) independently-driven wheels provide for rover locomotion and hill-climbing. Vehicle systems are typical with provision made for power generation, storage and distribution, vehicle guidance, navigation and control, data management, communication, and thermal control.
MER-A (Spirit) was launched on Tuesday, 10 June 2003 from SLC-17A at Cape Canaveral. Following a nominal entry and descent, the rover landed near Gusev Crater at 04:35 Ground UTC on Sunday, January 4, 2004. MER-B (Opportunity) was launched on Monday, 07 July 2003 from SLC-17B at Cape Canaveral. MER-B safely landed near Meridiani Planum at 05:05 Ground UTC on Sunday, 25 January 2004.
Both MER vehicles have produced images of and obtained scientific data on a myriad of Martian geologic features as they have roamed the region around their respective landing sites. They have operated for several thousand days beyond their 90-day design mission. That stunning success is due in great measure to the talented and dedicated mission operations and science teams back here on Earth.
In truth, any attempt to accurately synopsize here the myriad discoveries and scientific contributions of Spirit and Opportunity does both a disservice. Thus, to better grasp and appreciate the true scope and character of their incredible achievements, the reader is hereby invited to visit the following URL: http://marsrovers.jpl.nasa.gov/mission/status.html
Spirit was last heard from officially on Monday, 22 March 2010 (2,210 Mars days on the surface). The senior rover had traveled 4.8 miles during its many exploratory surface roamings. It is suspected that the vehicle is hibernating due to seasonally-low solar power levels. The hope is that Spirit will revive from its cold winter slumber when spring arrives this March at Gusev Crater.
As for Opportunity, it continues to continue! As of this writing, the junior rover is conducting a site survey at Crater Rim. It has been on the surface for 2,489 Mars days and has traveled in excess of 16.5 miles. Where this marvelous story ends is not clear at present. However, we do not have to wait for the day when MER-B finally goes silent to realize what has long been apparent; our noble exploratory marvel has afforded us a rare Opportunity indeed.
Fifty-one years ago this month, a developmental version of the USN/Lockheed Polaris A1 Fleet Ballistic Missile was test-flown from Cape Canaveral, Florida. The successful test marked a key milestone in the flight-proving of the Polaris missile’s Inertial Navigation System (INS).
The Cold War between the United States and the Soviet Union spawned the development of a Nuclear Triad by both sides. The concept involved delivery of atomic weapons via manned bombers, land-based ballistic missiles and submarine-launched ballistic missiles. This diversity of delivery systems thus provided for deterrence by maximizing the ability for either side to retaliate in the event of a first strike by the other.
The submarine-launched ballistic missile (SLBM) is arguably the most effective leg of the Nuclear Triad when its comes to deterrence. This effectiveness stems largely from the mobility and elusiveness of the nuclear-powered submarine itself. The fact that the missile is launched while the launch platform is submerged greatly enhances the weapons’s effectiveness as well.
The challenges faced by the Navy and its contractors in developing a SLBM capability were numerous and significant. Critical among these was the need to avoid igniting the first stage rocket motor within the confines of the submarine. The solution was to eject the missile from its launch canister via a high pressure gas generation system. The rocket was then air-ignited just after it broached the ocean surface.
A key aspect of the SLBM launch process is missile stability and control both in the water and in the air. During its underwater transit from canister eject to surface broach, the missile is not under active control. However, it must be statically stable in a hydrodynamic environment. Once in the air, the rocket motor must be ignited quickly since missile 3-axis control comes only via thrust vectoring.
Polaris was the first SLBM developed and deployed by the United States. Lockheed Space and Missile Systems (LSMS) began engineering development of the Navy missile in the mid-1950’s. Aerojet was the Polaris Program’s propulsion contractor. Flight testing from land-based launch pads began in 1958 with the first submarine-based launch occuring in mid-1960.
The Polaris A1 was a two-staged launch vehicle. It measured 28.5 feet in length and had a maximum diameter of 54-inches. Weight at first stage ignition was 28,800 pounds. The type’s MK 1 reentry body delivered a single MK 47 warhead having a yield of 600 kT. Maximum range was on the order of 1,200 nm.
On Thursday, 07 January 1960, Polaris A1X-7 was launched from LC-29A at Cape Canaveral, Florida. The primary purpose of the test was to prove the proper operation of the Inertial Navigation System (INS). This system was developed jointly by MIT and the General Electric Company. The missile flew 900 nm down the Eastern Test Range (ETR). The flight was entirely successful.
Thirty-four (34) more tests in the Polaris A1X series took place by early July of 1960. The majority were successful. All set the stage for the first submarine-launch of the Polaris from a submerged Navy submarine. Indeed, Polaris A1E-1 did so on Wednesday, 20 July 1960. It was followed less than three (3) hours later by Polaris A1E-2. Both missiles were launched from the USS George Washington (SSBN-598) in the waters near Cape Canaveral. Both flights were successful.
The Polaris A1 became operational in November of 1960. It was followed in 1962 and 1964 by the more capable A2 and A3 Polaris variants, respectively. In the never-ending quest for greater performance and effectiveness, the Polaris was eventually replaced by the Poseidon in the 1970’s. The latter was subsequently replaced in the 1990’s with the mighty Trident II D5 missile which serves up to the present day as the Nation’s premier SLBM.
Forty-seven years ago today, a USAF/Boeing B-52H Stratofortress landed safely following structual failure of its vertical tail during an encounter with unusually severe clear air turbulence. The harrowing incident occurred as the aircraft was undergoing structural flight testing in the skies over East Spanish Peak, Colorado.
Turbulence is the unsteady, erratic motion of an atmospheric air mass. It is attributable to factors such as weather fronts, jet streams, thunder storms and mountain waves. Turbulence influences the motion of aircraft that are subjected to it. These effects range from slight, annoying disturbances to violent, uncontrollable motions which can structurally damage an aircraft.
Clear Air Turbulence (CAT) occurs in the absence of clouds. Its presence cannot be visually observed and is detectable only through the use of special sensing equipment. Hence, an aircraft can encounter CAT without warning. Interestingly, the majority of in-flight injuries to aircraft crew and passengers are due to CAT.
On Friday, 10 January 1964, USAF B-52H (S/N 61-023) took-off from Wichita, Kansas on a structural flight test mission. The all-Boeing air crew consisted of instructor pilot Charles Fisher, pilot Richard Curry, co-pilot Leo Coors, and navigator James Pittman. The aircraft was equipped with accelerometers and other sensors to record in-flight loads and stresses.
An 8-hour flight was scheduled on a route that from Wichita southwest to the Rocky Mountains and back. The mission called for 10-minutes runs of 280, 350 and 400 KCAS at 500-feet AGL using the low-level mode of the autopilot. The initial portion of the mission was nominal with only light turbulence encountered.
However, as the aircraft turned north near Wagon Mound, Mexico and headed along a course parallel to the mountains, increasing turbulence and tail loads were encountered. The B-52H crew then elected to discontinue the low level portion of the flight. The aircraft was subsequently climbed to 14,300 feet AMSL preparatory to a run at 350 KCAS.
At approximately 345 KCAS, the Stratofortress and its crew experienced an extreme turbulence event that lasted roughly 9 seconds. In rapid sequence the aircraft pitched-up, yawed to the left, yawed back to the right and then rolled right. The flight crew desperately fought for control of their mighty behemoth. But it looked grim. The order was given to prepare to bailout.
Finally, the big bomber’s motion was arrested using 80% left wheel authority. However, rudder pedal displacement gave no response. Control inputs to the elevator produced very poor response as well. Directional stability was also greatly reduced. Nevertheless, the crew somehow kept the Stratofortress flying nose-first.
The B-52H crew informed Boeing Wichita of their plight. A team of Boeing engineering experts was quickly assembled to deal with the emergency. Meanwhile, a Boeing-bailed F-100C formed-up with the Stratofortress and announced to the crew that most of the aircraft’s vertical tail was missing! The stricken aircraft’s rear landing was then deployed to add back some directional stability.
With Boeing engineers on the ground working with the B-52H flight crew, additional measures were taken in an effort to get the Stratofortress safely back on the ground. These measures included a reduction in airspeed, controlling center-of-gravity via fuel transfer, use of differential thrust and selected application of speedbrakes.
Due to high surface winds at Wichita, the B-52H was vectored to Eaker AFB in Blytheville, Arkansas. A USAF/Boeing KC-135 was dispatched to escort the still-flying B-52H to Eaker and to serve as an airborne control center as both aircraft proceeded to the base. Amazingly, after flying 6 hours sans a vertical tail, the Stratofortress and her crew landed safely.
Safe recovery of crew and aircraft brought additional benefits. There were lots of structural flight test data! It was found that at least one gust in the severe CAT encounter registered at nearly 100 mph. Not only were B-52 structural requirements revised as a result of this incident, but those of other existing and succeeding aircraft as well.
B-52H (61-023) was repaired and returned to the USAF inventory. It served long and well for many years after its close brush with catastrophy in January 1964. The aircraft spent the latter part of its flying career as a member of the 2nd Bomb Wing at Barksdale AFB, Louisiana. The venerable bird was retired from active service in July of 2008.
Sixty-two years ago this week, the USAF/Bell XS-1 became the first aircraft of any kind to achieve supersonic flight from a ground take-off. The daring feat took place at Muroc Air Force Base with USAF Captain Charles E. Yeager at the controls of the XS-1.
Rocket-powered X-aircraft such as the XS-1, X-1A, X-2 and X-15 were air-launched from a larger carrier aircraft. With the test aircraft as its payload, this “mothership” would take-off and climb to drop altitude using its own fuel load. This permitted the experimental aircraft to dedicate its entire propellant load to the flight research mission proper.
The USAF/Bell XS-1 was the first X-aircraft. It was carried to altitude by a USAF/Boeing B-29 mothership. XS-1 air-launch typically occurred at 220 mph and 22,000 feet. On Tuesday, 14 October 1947, the XS-1 first achieved supersonic flight. The XS-1 would ultimately fly as fast as Mach 1.45 and as high as 71,902 feet.
All but two (2) of the early X-aircraft were Air Force developments. The exceptions were products of the United States Navy flight research effort; the USN/Douglas D-558-I Skystreak and USN/Douglas D-558-II Skyrocket. The Skystreak was a turbojet-powered, straight-winged, transonic aircraft. The Skyrocket was supersonic-capable, swept-winged, and rocket-powered. Each aircraft was ground-launched.
In the best tradition of inter-service rivalry, the Navy claimed that the D-558-I was the only true supersonic airplane since it took to the air under its own power. Interestingly, the Skystreak was able fly beyond Mach 1 only in a steep dive. Nonetheless, the Air Force was indignant at the Navy’s insinuation that the XS-1 was somehow less of an X-aircraft because it was air-launched.
Motivated by the Navy’s afront to Air Force honor, the junior military service devised a scheme to ground-launch the XS-1 from Rogers Dry Lake at Muroc (now Edwards) Air Force Base. The aircraft would go supersonic in what was essentially a high performance take-off and climb. To boot, the feat was timed to occur just before the Navy was to fly its rocket-powered D-558-II Skyrocket. Justice would indeed be rendered!
XS-1 Ship No. 1 (S/N 46-062) was selected for the ground take-off mission. Captain Charles E. Yeager would pilot the sleek craft with Captain Jackie L. Ridley providing vital engineering support. Due to its delicate landing gear, the XS-1 propellant load was restricted to 50% of capacity which provided about 100 seconds of powered flight.
On Wednesday, 05 January 1949, Yeager fired all four (4) barrels of his XLR-11 rocket motor. Behind 6,000 pounds of thrust, the XS-1 quickly accelerated along the smooth surface of the dry lake. After a take-off roll of 1,500 feet and with the XS-1 at 200 mph, Yeager pulled back on the control yoke. The XS-1 virtually leapt into the air.
The aerodynamic loads were so high during gear retraction that the actuator rod broke and the wing flaps tore away. Unfazed, Yeager’s eager steed climbed rapidly. Eighty seconds after brake release, the XS-1 hit Mach 1.03 passing through 23,000 feet. Yeager then brought the XS-1 to a wings level flight attitude and shutdown his XLR-11 powerplant.
Following a brief glide back to the dry lake, Yeager executed a smooth dead-stick landing. Total flight time from lift-off to touchdown was on the order of 150 seconds. While a little worst for wear, the plucky XS-1 had performed like a champ and successfully accomplished something that it was really not designed to do.
Yeager was so excited during the take-off roll and high performance climb that he forgot to put his oxygen mask on! Potentially, that was a problem since the XS-1 cockpit was inerted with nitrogen. Fortunately, late in the climb, Yeager got his mask in place just before he went night-night for good.
Suffice it to say that the United States Navy was not particularly fond of the display of bravado and airmanship exhibited on that long-ago January day. The Air Force had emerged victorious in a classic contest of one-upmanship. Indeed, Air Force honor had been upheld. And, as was often the case in the formative years of the United States Air Force, it was Chuck Yeager who brought victory home to the blue suiters.
Thirty-eight years ago this month, NASA successfully conducted the sixth lunar landing mission of the Apollo Program. Known as Apollo 17, the flight marked the last time that men from the planet Earth explored the surface of the Moon.
Apollo 17 was launched from LC-39A at Cape Canaveral, Florida on Thursday, 07 December 1972. With a lift-off time of 05:33:00 UTC, Apollo 17 was the only night launch of the Apollo Program. Those who witnessed the event say that night turned into day as the incandescent exhaust plumes of the Saturn V’s quintet of F-1 engines lit up the sky around the Cape.
The target for Apollo 17 was the Taurus-Littrow valley in the lunar highlands. Located on the southeastern edge of Mare Serenitatis, the landing site was of particular interest to lunar scientists because of the unique geologic features and volcanic materials resident within the valley. Planned stay time on the lunar surface was three days.
The Apollo 17 crew consisted of Commander Eugene A. Cernan, Command Module Pilot (CMP) Ronald E. Evans and Lunar Module Pilot (LMP) Harrison H. Schmitt. While this was Cernan’s third space mission, both Evans and Schmitt were space rookies. Astronaut Schmitt was a professional geologist and the only true scientist to explore the surface of the Moon.
With Evans circling the Moon solo in the Command Module America, Cernan and Schmitt successfully landed their Lunar Module Challenger at 19:54:57 UTC on Monday, 11 December 1972. Their lunar stay lasted more than three days. The astronauts used the Lunar Rover for transport over the lunar surface as they conducted a trio of exploratory excursions that totaled more than 22 hours.
Cernan and Schmitt collected nearly 244 pounds of lunar geologic materials while exploring Taurus-Littrow. As on previous missions, the Apollo 17 crew deployed a sophisticated set of scientific instruments used to investigate the lunar surface environment. Indeed, the Apollo Lunar Surface Experiments Package (ALSEP) deployed during during lunar landing missions measured and transmitted vital lunar environmental data back to Earth through September 1977 when the data acquisition effort was officially terminated.
The Apollo 17 landing party departed the Moon at 22:54:37 UTC on Thursday, 14 December 1972. In a little over two hours, Challenger and America were docked. Following crew and cargo transfer to America, Challenger was later intentionally deorbited and impacted the lunar surface. The Apollo 17 crew then remained in lunar orbit for almost two more days to make additional measurements of the lunar environment.
At 23:35:09 UTC on Saturday, 16 December 1972, Apollo 17 blasted out of lunar orbit and headed home. Later, CMP Ron Evans performed a trans-Earth spacewalk to retrieve film from Apollo 17 ‘s SIM Bay camera. Evans’ brave spacewalk occurred on Sunday, 17 December 1972 (69th anniversary of the Wright Brothers first powered flight) and lasted 65 minutes and 44 seconds.
Apollo 17 splashdown occurred near America Samoa in the Pacific Ocean at 19:24:59 UTC on Tuesday, 19 December 1972. America and her crew were subsequently recovered by the USS Ticonderoga.
Apollo 17 set a number of spaceflight records including: longest manned lunar landing flight (301 hours, 51 minutes, 59 seconds); longest lunar stay time (74 hours, 59 minutes, 40 seconds); total lunar surface extravehicular activity time (22 hours, 3 minutes, 57 seconds); largest lunar sample return (243.7 pounds), and longest time in lunar orbit (147 hours, 43 minutes, 37 seconds).
Apollo 17 successfully concluded America’s Apollo Lunar Landing Program. Of a sudden it seemed, America’s — and the world’s — greatest adventure was over. However, the anticipation was that the United States would return in the not-too-distant future. Indeed, Gene Cernan, the last man to walk on the Moon, spoke the following words from the surface:
“As I take man’s last step from the surface, back home for some time to come — but we believe not too long into the future — I’d like to just [say] what I believe history will record — that America’s challenge of today has forged man’s destiny of tomorrow. And, as we leave the Moon at Taurus-Littrow, we leave as we came and, God willing, as we shall return, with peace and hope for all mankind. Godspeed the crew of Apollo 17.”
It has now been 38 years since the Commander of Apollo 17 spoke those stirring words from the valley of Taurus-Littrow. Gene Cernan and most space experts of his day figured we would surely be back by now. Certainly in the 20th century. Yet, there has been no return. Moreover, there is no formal plan or funded program in the 21st century to do so. And so, the historical record continues to list the name of Eugene A. Cernan as the last man to walk on the Moon.
Okay America, here’s some questions for you. When will we go back to the Moon? By extension, how about Mars and beyond? Are our greatest space achievements behind us or is the best yet to come? Are we a nation of used-to-be’s or are we that bastion of freedom where even the impossible is achievable? Does it matter? Do you even care? You choose.
Fifty-six years ago this month, USAF Lieutenant Colonel John Paul Stapp set a record for human G-tolerance when his Sonic Wind #1 rocket-powered test sled decelerated from 632 mph to a full stop in roughly 1.4 seconds. In so doing, Stapp endured a deceleration load equal to 46.2 times his weight.
The period immediately following World War II marked the beginning of a steady rise in the speed and altitude capabilities of military aircraft. These performance increases subjected aircrew to wider ranges of flight loads and physical stresses. Manifold aeromedical issues and crew safety concerns arose; particularly in the area of emergency escape from a stricken aircraft.
Abandoning an aircraft in flight under emergency conditions and surviving the experience has always been a sporty proposition. Ejection forces, wind blast, body limb flailing, parachute opening shock levels, and the like make it so. Add to this list the effects of atmospheric temperature, pressure and oxygen concentration, and one starts to get an appreciation for the severity of the situation.
John Paul Stapp was a USAF physician who had an abiding interest in the aeromedical aspects of emergency escape. He knew that too many pilots were dying in situations that could have been survivable if proper equipment and procedures were available. Stapp dedicated himself to improving the chances of aircrew survival.
Stapp was a pioneer in scientifically investigating the effects of acceleration and deceleration on the human body. In March of 1947, he began a series of deceleration tests using a 2,000-foot sled track at Edwards Air Force Base. A rocket-powered test sled named the Gee Whiz carried test subjects down the track and brought them to a sudden halt to produce specific deceleration levels.
Initially, Stapp’s test subjects were anthropomorphic dummies and primates. However, he had always held to the belief that the best test subject would be a human. Better yet, a human who possessed extensive medical knowledge. Stapp selected himself for the assignment.
Stapp took his first ride down the Edwards sled test track on Wednesday, 10 December 1947. By May of 1948, he had riden the Gee Whiz a total of 16 times. One run resulted in a deceleration of 35-G’s. This meant that Stapp briefly experienced a force equal to 35 times his normal body weight during deceleration. In so doing, he pointedly dispelled the prevailing notion that a human being could not survive a deceleration level beyond 18-G’s.
Riding the sled was a form of physical abuse. Among numerous injuries, Stapp received several concussions, broke the same wrist twice, cracked ribs, and sustained retinal hemorrhages for his time on the track. All in an effort to find ways to preserve the lives of aircrew. Stapp, other human volunteers and chimpanzees continued sled testing on the Edwards track until 1953.
Stapp transferred to the Aeromedical Field Lab at Holloman Air Force Base, New Mexico in early 1953. He now had a longer track (3,550 feet) and a faster sled (Sonic Wind #1) with which to expand his deceleration research. The system was checked-out using a new crash test dummy and then a live primate. Stapp made the first human run on the Holloman track.
John Paul Stapp completed his 29th and final experimental sled test run on Friday, 10 December 1954. Propelled by a set of 9 rocket motors producing 70,000 pounds of thrust, the Sonic Wind #1 hit a peak velocity of 632 mph (Mach 0.9 at the test site altitude). Stapp endured a maximum acceleration of 20 G’s and then an incredible peak deceleration of 46.2-G’s during 1.4 seconds of slow-down. At that moment, he weighed 6,800 pounds.
Stapp took a severe pounding during his record ride. There were the “usual” body bruises, lacerations and harness burns. However, the worse effects involved his eyes. Both hemorrhaged and were completely filled with blood. Stapp indicated that all he could see was a watery salmon-colored fluid. Happily, his vision would return to quasi-normal by the next day. Stapp sported a pair of world-class shiners as peculiar momentos of his extreme deceleration experience.
Characteristically, Stapp had plans to go faster and endure more G’s. Indeed, the proposed Sonic Wind #2 test sled would be capable of driving him in excess of 1,000 mph and decelerating at more than 80 G’s. Such was not to occur as USAF would not allow Stapp to risk all again as a sled test subject.
John Paul Stapp’s legendary work produced enormous dividends in helping develop equipment, techniques and procedures that have saved the lives of countless aircrew. But the benefits of his research have gone well beyond that. Today, automobile safety standards are based in large measure on Stapp’s pioneering deceleration work. His legacy continues in other ways as well. Indeed, the 54th Stapp Car Crash Conference was held in November of this year.
John Paul Stapp, USAF officer, physician, sled test subject, was a man of uncommon valor and a bonifide hero in the truest sense of that over-used word. He willingly risked his life numerous times so that others might live. A man can do no more than that for his friends. On Wednesday, 13 November 1999, this man among men passed away peacefully in his sleep at age 89.
Fifty-one years ago this week, USAF Captain Joe B. Jordan zoomed a modified USAF/Lockheed F-104C Starfighter to a world altitude record of 103,395.5 feet above mean sea level. The flight originated from and recovered to the Air Force Flight Test Center (AFFTC) at Edwards Air Force Base, California.
On Tuesday, 14 July 1959, the USSR established a world altitude record for turbojet-powered aircraft when Soviet test pilot Vladimir S. Ilyushin zoomed the Sukhoi T-43-1 (a prototype of the Su-9) to an absolute altitude of 94,661 feet. By year’s end, the Soviet achievement would be topped by several American aircraft.
FAI rules stipulate that an existing absolute altitude record be surpassed by at least 3 percent for a new mark to be established. In the case of the Soviet’s 1959 altitude record, this meant that an altitude of at least 97,501 feet would need to be achieved in a record attempt.
On Sunday, 06 December 1959, USN Commander Lawrence E. Flint wrested the months-old absolute altitude record from the Soviets by zooming to 98,561 feet. Flint piloted the second USN/McDonnell Douglas YF4H-1 (F4 Phantom II prototype) in accomplishing the feat. In a show of inter-service cooperation, the record flight was made from the AFFTC at Edwards Air Force Base.
Meanwhile, USAF was feverishly working on its own record attempt. The aircraft of choice was the Lockheed F-104C Starfighter. However, with the record now held by the Navy, the Starfighter would have to achieve an absolute altitude of at least 101,518 feet to set a new mark. (Per the FAI 3 percent rule.)
On Tuesday, 24 November 1959, the AFFTC accepted delivery of the record attempt aircraft, F-104C (S/N 56-0885), from the Air Force Special Weapons Center at Kirtland AFB in New Mexico. This aircraft was configured with a J79-GE-7 turbojet capable of generating nearly 18,000 pounds of sea level thrust in afterburner.
Modifications were made to the J79 to maximize the aircraft’s zoom kinematic performance. The primary enhancements included increasing afterburner fuel flow rate by 10 percent and maximum RPM from 100 to 103.5 percent. Top reset RPM was rated at 104.5 percent. Both the ‘A’ and ‘B’ engine flow bypass flaps were operated in the open position as well. These changes provided for increased thrust and stall margin.
An additional engine mod involved reducing the minimum engine fuel flow rate from 500 to 250 pounds per hour. Doing so increased the altitude at which the engine needed to be shut down to prevent overspeed or over-temperature conditions. Another change included increasing the maximum allowable compressor face temperature from 250 F to 390 F.
The F-104C external airframe was modified for the maximum altitude mission as well. The compression cones were lengthened on the bifurcated inlets to allow optimal pressure recovery at the higher Mach number expected during the record attempt. High Mach number directional stability was improved by swapping out the F-104C empannage with the larger F-104B tail assembly.
USAF Captain Joe B. Jordan was assigned as the altitude record attempt Project Pilot. USAF 1st Lt and future AFFTC icon Johnny G. Armstrong was assigned as the Project Engineer. Following an 8-flight test series to shake out the bugs on the modified aircraft, the record attempt proper started on Thursday, 10 December 1959.
On Monday, 14 December 1959, F-104C (S/N 56-0885) broke the existing absolute altitude record for turbojet-powered aircraft on its 5th attempt. Jordan did so by accelerating the aircraft to Mach 2.36 at 39,600 feet. He then executed a 3.15-g pull to an inertial climb angle of 49.5 degrees. Jordan came out of afterburner at 70,000 feet and stop-cocked the J79 turbojet at 81,700 feet.
Roughly 105 seconds from initiation of the pull-up, Joe Jordan reached the top of the zoom. The official altitude achieved was 103,395.5 feet above mean sea level based on range radar and Askania camera tracking. True airspeed over the top was on the order of 455 knots. Jordan started the pull-up to level flight at 60,000 feet; completing the recovery at 25,000 feet. Landing was entirely uneventful.
Jordan’s piloting achievement in setting the new altitude record was truly remarkable. His conversion of kinetic energy to altitude (potential energy) during the zoom was extremely efficient; realizing only a 2.5 percent energy loss from pull-up to apex. Jordan also exhibited exceptional piloting skill in controlling the aircraft over the top of the zoom where the dynamic pressure was a mere 14 psf. He did so using aerodynamic controls only. The aircraft did not have a reaction control system ala the X-15.
Armstrong’s contributions to shattering the existing altitude record were equally substantial. Skillful flight planning and effective use of available resources (including time available for the record attempt) were pivotal to mission success. Armstrong significantly helped maximize aircraft zoom performance through proper selection of pull-up flight conditions and intelligent use of accurate day-of-flight meteorological information.
For his skillful piloting efforts in setting the world absolute altitude record for turbojet-powered aircraft in December of 1959, Joe Jordan received the 1959 Harmon Trophy.
Forty-five years ago this month, Gemini 7 set a new record for long-duration manned spaceflight. The official lift-off-to-splashdown flight duration was 330 hours, 35 minutes and 1 second.
Project Gemini was the critical bridge between America’s fledging manned spaceflight effort – Project Mercury – and the bold push to land men on the Moon – Project Apollo. While the events and importance of this program have faded somewhat with the passage of time, there would have been no manned lunar landing in the decade of the 1960’s without Project Gemini.
On Thursday, 25 May 1961, President John F. Kennedy addressed a special session of the U.S. Congress on the topic of “Urgent National Needs”. Near the end of his prepared remarks, President Kennedy proposed that the United States “should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth.”
At the time of the President’s clarion call to go to the Moon, the United States had accrued a total of 15 minutes of manned spaceflight experience. That quarter hour of spacefaring activity had come just 20 days previous. Indeed, Alan B. Shephard became the first American to be launched into space when he rode his Freedom 7 Mercury spacecraft on a sub-orbital trajectory down the Eastern Test Range on Tuesday, 05 May 1961.
America responded enthusiastically to the manned lunar landing goal. However, no one really knew exactly how to go about it! After considering several versions of direct ascent from the Earth to the Moon, NASA ultimately decided to use a method proposed by engineer John C. Houbolt known as Lunar Orbit Rendezvous (LOR). As a result, NASA would have to invent and master the techniques of orbital rendezvous.
Project Gemini provided the technology and flight experience required for a manned lunar landing and return. In the 20 months between March of 1965 and November of 1966, a total of 10 two-man Gemini missions were flown. During that time, the United States learned to navigate, rendezvous and dock in space, fly for long durations and perform extra-vehicular activities.
The primary purpose of Gemini 7 was to conduct a 14-day orbital mission. This was important since the longest anticipated Apollo mission to the Moon and back would be about the same length of time. Gemini 7 was flown to show that men and spacecraft could indeed function in space for the required period. A secondary goal of Gemini 7 was to serve as the target for Gemini 6 in achieving the world’s first rendezvous between two manned spacecraft.
Gemini-Titan (GT-7) lifted-off from Cape Canaveral’s LC-19 at 19:30:03 UTC on Saturday, 04 December 1965. The Gemini 7 flight crew consisted of Commander Frank F. Borman II and Pilot James A. Lovell, Jr. They were successfully inserted into a 177-nm x 87-nm low-earth orbit. This initial orbit was later circularized to 162-nm.
Borman and Lovell spent the first 10-days of their mission conducting a variety of space experiments. They wore special lightweight spacesuits that were supposed to improve confort level for their long stay in space. However, these suits were not all that comfortable and by their second week in space, the astronauts were flying in just their long-johns.
On their 11th day in space, the Gemini 7 crew had visitors. Indeed, Gemini 6 was launched into Earth orbit from Cape Canaveral and subsequently executed the first rendezvous in space with Gemini 7 on Wednesday, 15 December 1965. Gemini 6, with Commander Walter M. Schirra, Jr. and Pilot Thomas P. Stafford on board, ultimately maneuvered to within 1 foot of the Gemini 7 spacecraft.
While Gemini 6 returned to Earth within 24 hours of launch, Gemini 7 and her weary crew soldiered on. The monotony was brutal. Borman and Lovell had conducted all of their planned space experiments. They had to drift through space to conserve fuel. They couldn’t sleep because they weren’t tired. Borman later indicated that those last 3 days on board Gemini 7 were some of the toughest of his life.
On the 14th day of flight, Saturday, 18 December 1965, Borman and Lovell successfully returned to Earth. Reentry was entirely nominal. Splashdown occurred at 14:05:04 UTC in the Atlantic Ocean roughly 400 miles east of Nassau in The Bahamas. Crew and spacecraft were recovered by the USS Wasp.
Frank Borman and Jim Lovell had orbited the Earth 206 times during their 14-day mission. Each crew member was tired and a little unsteady as he walked the flight deck of the USS Wasp. However, each man quickly recovered his native strength and vitality.
The 14 days that the Gemini 7 crew spent in space were physically and emotionally demanding. Life within the cramped confines of their little spacecraft was akin to two guys living inside a telephone booth for two weeks. Notwithstanding the challenges of that spartan existence, the Gemini 7 crew did their job. Gemini 7 was a resounding success. More, Project Gemini had achieved another key milestone. The Moon seemed a bit closer.
Thirty-one years ago this month, the 2nd and only surviving USAF/Lockheed YF-12A completed its final NASA flight research mission. The flight brought to a close the 10-year period within which the YF-12A was employed as a NASA high-speed flight research platform.
The YF-12A was the interceptor variant of the vaunted Lockheed A-12 Mach 3+ aircraft. Armed with a quartet of Hughes AIM-47A air-to-air missiles, the YF-12A’s mission would be to intercept and destroy incoming Soviet bombers. Lockheed proposed the A-12 variant as a cost-effective replacement for the defunct North American XF-108 Rapier.
The YF-12A differed from the A-12 in that a second crew station was added for the AIM-47A Weapons Systems Officer (WSO). The WSO operated the powerful Hughes AN/ASG-18 fire control radar which had a range on the order of 500 miles. The YF-12A’s forebody chines were truncated back of the axisymmetric nose to accommodate the radar system. Infrared (IR) sensors were installed on the leading edges of the shortened chines.
The Hughes AIM-47A missile measured 12.5 feet in length and 13.5 inches in diameter. Maximum range of the 800-pound missile was in excess of 100 miles. While the type’s intended maximum Mach number was 6, propulsion system development problems limited the demonstrated maximum Mach number to 4. About eighty (80) AIM-47A missiles were produced. Seven (7) of these rounds were test fired in flight. All but one (1) was successful.
Lockheed converted a trio of A-12 aircraft to the YF-12A configuration. The YF-12A aircraft were assigned serial numbers 60-6934 (Ship 1), 60-6935 (Ship 2) and 60-6936 (Ship 3). Ship 1 made the maiden YF-12A flight from Groom Lake, Nevada on Wednesday, 07 August 1963 with James D. Eastham at the controls.
Over the next eighteen (18) months, all three (3) YF-12A aircraft were put through performance flight testing at Groom Lake. Ship 3 set a number of speed and altitude records on Saturday, 01 May 1965. Included was the first air-breathing aircraft speed record in excess of 2,000 mph (2,070.102 mph) and a sustained altitude record of 80,257.86 feet above mean sea level.
USAF liked the YF-12A’s demonstrated performance capabilities. Thus, on Friday, 14 May 1965, the service ordered ninety-three (93) units of the production YF-12A aircraft known as the F-12B. Congress approved the order and allotted $90M to get production going. Unfortunately, United States Secretary of Defense Robert S. McNamara nixed the deal and cancelled the production of the F-12B.
Recall that McNamara also cancelled the XB-70A and X-20A Dyna-Soar and was the genius who championed the ill-posed TFX multiservice aircraft concept. He was also responsible for crafting the absurd rules of air war engagement that resulted in the inordinately large and unnecessary losses of American pilots in Viet Nam. McNamara further cemented his status as the Bane of the U.S. Air Force with the F-12B production wave-off.
Following the F-12B cancellation, YF-12A flight testing by USAF continued through 1969. One aircraft was lost along the way. On Thursday, 14 August 1966, Ship 1 was severely damaged in a landing incident at Edwards AFB and never flew again. Happily, the crew escaped injury.
In December of 1969, NASA initiated a flight research effort using YF-12A Ship 2 and Ship 3. Over the next ten (10) years a wealth of aerodynamic, aero heating, structural and propulsion flight research data were acquired using these unique high-speed assets. A great benefit in this regard was the type’s ability to sustain Mach 3+ flight conditions for periods up to 15 minutes per mission.
YF-12A Ship 3 was lost on Thursday, 24 June 1971 when an inflight fire started due to a failed fuel line in the right-hand J58 turbo-ramjet engine. The USAF crew of pilot Lt Col Ronald J. Layton and WSO Maj William A. Curtis attempted to recover the aircraft to Edwards AFB. However, the fire quickly spread and forced the crew to abandon the aircraft. They ejected safely and survived. Ship 3 was making its 67th flight of the NASA YF-12A flight research effort at the time of its demise.
Following Ship 3’s loss, Ship 2 flew the remainder of the NASA YF-12A high-speed flight research program. It registered a total of 146 missions in that capacity. On Wednesday, 07 November 1979, YF-12A Ship 2 departed Edwards AFB for its final destination; the USAF Musuem at Wright-Patterson AFB, Ohio. The USAF crew consisted of pilot Col James V. Sullivan and USAF Museum Director Richard Uppstrom as the guy in back (GIB).
As a footnote to the current story, the USAF attempted throughout the 1950’s and 1960’s to develop and produce a Mach 3 interceptor. Notable abortive attempts include the Republic XF-103 Thunder Warrior, the North American XF-108 Rapier and the Lockheed F-12B. Doubtless, there have been failed black-world attempts as well. The net result is that a Mach 3 interceptor has yet to grace the USAF production aircraft inventory.
Forty-four years ago this month, a prototype of the USAF/Douglas Manned Orbiting Laboratory (MOL) was launched into Earth orbit. It was the first and only orbital flight test of the military space station.
The Manned Orbiting Laboratory (MOL) was a United States Air Force (USAF) program to develop a military reconnaissance space platform in the 1960’s. Using advanced optic, camera and radar systems, the MOL’s military astronaut crew would have the capability to determine the nature of other countries’ military spaceflight activities. Of particular interest were the clandestine military activities of the Soviet Union and Red China.
Operational MOL missions were to be launched from Vandenberg Air Force Base (VAFB) on the California coast. Doing so would provide a polar orbit capability. The corresponding high orbital inclination meant that the MOL would overfly much of the Earth’s surface during a 24-hour period.
The MOL Program was formally announced to the American public in December of 1963. The prime contractor was the Douglas Aircraft Company (DAC). The MOL was a large cylinder that measured 72-ft in length and 10-ft in diameter. The MOL consisted of 5 segments; main cabin, auxiliary cabin, experiment module, equipment module and a propulsion stage. MOL GTOW was approximately 32,000 lbs.
Fixed atop the MOL was a variant of the NASA Gemini spacecraft known as Gemini B. The crew would ride into and out of orbit in this vehicle. Access to the MOL was via a small door built into the Gemini’s heat shield. Once inside the MOL, the crew would doff their spacesuits and live in a “shirt-sleeve” environment. MOL was to use a two-gas atmosphere (70% oxygen-30% helium). A typical MOL mission was on the order of 30 days.
The Gemini-MOL combination was to be boosted into orbit by a Titan IIIC launch vehicle. First stage propulsion consisted of a pair of solid rocket boosters and a liquid sustainer core. Total lift-off thrust was about 1.84 million pounds. Second stage thrust was on the order of 100,000 pounds. The Titan IIIC third stage was the MOL transtage which produced 16,000 pounds of thrust.
Seventeen (17) MOL astronauts were selected in three (3) groups from the military services. MOL Group 1 (November 1965), MOL Group 2 (June 1966) and MOL Group 3 (June 1967) consisted of eight (8), five (5) and four (4) selectees, respectively. None of these men ever flew a MOL mission. However, seven (7) went on to fly on the Space Shuttle.
On Thursday, 03 November 1966, the one and only flight test of the MOL Program took place. Lift-off from Cape Canaveral’s LC-40 occurred at 13:50:42 UTC. A Titan II propellant tank served as the MOL test article. The previously-flown Gemini 2 spacecraft was employed as a representation of the Gemini B vehicle. The lone MOL prototype flight test was unmanned.
During Titan IIIC ascent, the Gemini 2 spacecraft separated and executed a sub-orbital reentry. The vehicle splashed-down in the South Atlantic Ocean near Ascension Island and was recovered by the USS La Salle. Post-flight inspection of the vehicle’s heat shield hatch revealed that it came through the reentry intact.
Meanwhile, the Titan IIIC launch vehicle successfully orbited the MOL prototype. In addition, a trio of satellites that had accompanied the MOL mock-up was successfully injected into Earth orbit. Thus, the first and only flight test in the history of the MOL Program was entirely successful.
Despite its game-changing mission, a successful flight test and its technical feasibility, the MOL Program never achieved operational status. It was cancelled by U.S. Secretary of Defense Melvin Laird in 1969. The cancellation came at a time when the country had invested heavily in the Apollo Program throughout the 1960’s, the Viet Nam War was escalating and unmanned satellite sensing technology was greatly improved.
The MOL cancellation was a real shot to the solar plexis of the American aerospace industry. Coupled with the contemporaneous ramp-down of the Apollo engineering and development effort, American aerospace would never again see the breath and depth of financial investment it enjoyed in the 1950’s and 1960’s.
The lone surviving physical artifact of the MOL Program was the twice-flown Gemini 2 spacecraft. It is on display today at the Air Force Space and Missile Museum at Cape Canaveral, Florida.
Twenty-nine years ago this month, the Space Shuttle Columbia completed the second mission of the Space Shuttle Program. Designated STS-2, the mission marked the first reuse of a space vehicle for manned orbital flight.
America’s early manned spacecraft – Mercury, Gemini and Apollo – were single-flight vehicles. That is, a new spacecraft was required for each space mission. This was appropriate for meeting the aims of the early space program which concentrated on getting America to the moon before the end of the 1960’s.
The concept of space vehicle reusability came into vogue with the introduction of the Space Transportation System (STS). The original goal of the STS was to provide frequent and routine access to space via a fleet of Space Shuttle vehicles. For the STS to achieve economic viability, this meant flying a Space Shuttle once every two weeks. History has shown that this projected flight rate was optimistic to say the least.
The Space Shuttle vehicle was ultimately configured as a 3-element system consisting of (1) a winged orbiter, (2) a pair of solid rocket boosters (SRB’s) and (3) an external tank (ET). Both the orbiter and the SRB’s were designed to be reusable. The ET would be the only disposable element of the system since higher costs would be incurred in the recovery and refurbishment of this piece of flight hardware than in simply using a new one for each flight.
The Space Shuttle was designed to haul large payloads; on the order of 60,000 and 50,00 lbs into and out of orbit, respectively. With a maximum landing weight of 230,000 lbs, the Space Shuttle Orbiter needed wings to generate the required aerodynamic lift force. Wings were needed to satisfy the Orbiter’s 1,100-nm entry cross range requirement as well.
Following the successful first flight (STS-1) of the Space Shuttle Columbia in April of 1981, preparations began immediately to ready the Orbiter for its equally monumental second flight. The STS-2 flight crew would consist of Commander Joe Henry Engle and Pilot Richard Harrison Truly. STS-2 would be the first orbital spaceflight for both men.
On Thursday, 12 November 1981, the Space Shuttle Columbia lifted-off at 15:09:59 UTC from Cape Canaveral’s LC-39A. Ascent flight was nominal and Columbia was placed into a 125-nm x 120-nm orbit. At this point, Columbia became the first manned spacecraft to achieve Earth-orbit twice. It was an extra special occasion for Richard Truly inasmuch as it was his 44th birthday.
Engle and Truly anticipated 5-days in orbit with their orbital steed. However, one of Columbia’s three fuel cells failed early-on and the mission was reduced to just over two days. Nonetheless, the crew achieved 90 percent of the mission’s goals. They even remained awake during a scheduled sleep period to exercise the new Canadian Remote Manipulator System (RMS).
On Saturday, 14 November 1981, Columbia and her crew successfully completed STS-2 by landing on Rogers Dry Lake at Edwards Air Force Base, California. Main gear touchdown occurred at 21:23:11 UTC. Joe Engle flew the entire reentry manually. He holds the distinction of being the only pilot to manually fly a lifting space vehicle all the way from orbit to landing. Engle completed a total of 29 Programmed Test Input (PTI) aerodynamic maneuvers in the process.
STS-2 was a monumental success. Columbia became the first space vehicle to be reused for manned orbital space operations. Other Orbiters would follow including Challenger, Atlantis, Discovery and Endeavor. As of this writing, 132 STS missions have been flown.
As a footnote, Joe Engle went on to command one more Space Shuttle mission in 1985 (STS-51I). He retired from the USAF in November of 1986. Richard Truly served as Commander of STS-8 in 1983. That mission featured the first night launch and landing of the Space Shuttle. Richard Truly also served as NASA Administrator from May of 1989 to May of 1992.
Forty-nine years ago this week, the USAF/NASA/North American X-15 became the first manned aircraft to exceed Mach 6. United States Air Force test pilot Major Robert M. White was at the controls of the legendary hypersonic flight research aircraft.
The North American X-15 was the first manned hypersonic aircraft. It was designed, engineered, constructed and first flown in the 1950’s. As originally conceived, the X-15 was designed to reach 4,000 mph (Mach 6) and 250,000 feet. Before its flight test career was over, the type would meet and exceed both performance goals.
North American built a trio of X-15 airframes; Ship No. 1 (S/N 56-6670), Ship No. 2 (56-6671) and Ship No. 3 (56-6672). The X-15 measured 50 feet in length, had a wing span of 22 feet and a GTOW of 33,000 lbs. Ship No. 2 would later be modified to the X-15A-2 enhanced performance configuration. The X-15A-2 had a length of 52.5 feet and a GTOW of around 56,000 lbs.
The Reaction Motors XLR-99 rocket engine powered the X-15. The small, but mighty XLR-99 generated 57,000 pounds of sea level thrust at full-throttle. It weighed only 910 pounds. The XLR-99 used anhydrous ammonia and LOX as propellants. Burn time varied between 83 seconds for the stock X-15 and about 150 seconds for the X-15A-2.
The X-15 was carried to drop conditions (typically Mach 0.8 at 42,000 feet) by a B-52 mothership. A pair of aircraft were used for this purpose; a B-52A (S/N 52-003) and a B-52B (S/N 52-008). Once dropped from the mothership, the X-15 pilot lit the XLR-99 to accelerate the aircraft. The X-15A-2 also carried a pair of drop tanks which provided propellants for a longer burn time than was possible with the stock X-15 flight.
The X-15 employed both aerodynamic and reaction flight controls. The latter were required to maintain vehicle attitude in space-equivalent flight. The X-15 pilot wore a full-pressure suit in consequence of the aircraft’s extreme altitude capability. The typical X-15 drop-to-landing flight duration was on the order of 10 minutes. All X-15 landings were performed deadstick.
On Thursday, 09 November 1961, USAF Major Robert M. White would fly his 11th X-15 mission. The X-15 and White had already become respectively the first aircraft and pilot to hit Mach 4 and Mach 5. On this particular day, White would be at the controls of X-15 Ship No. 2. The planned maximum Mach number for the mission was Mach 6.
At 17:57:17 UTC of the aforementioned day, X-15 Ship No. 2 was launched from the B-52B mothership commanded by USAF Captain Jack Allavie. Bob White lit the XLR-99 and pulled into a steep climb. Mid-way through the climb, White pushed-over and ultimately leveled-off at 101,600 feet. XLR-99 burnout occurred 83 seconds after ignition. At this point, White was traveling at 4,093 mph or Mach 6.04.
On this record flight, the X-15 was exposed to the most severe aerodynamic heating environment it had experienced to date. Decelerating through Mach 2.7, the right window pane on the X-15’s canopy shattered due to thermal stress. The glass pane remained intact, but White could not see out of it. Fortunately, he could see out of the left pane and made a successful deadstick landing on Rogers Dry Lake at Edwards AFB.
For his Mach 6+ flight, Bob White was a recipient of both the 1961 Collier Trophy and the Iven C. Kincheloe Award. The year before, White had received the Harmon Trophy for his X-15 flight test work. He would go on to fly the X-15 to a still-standing FAI altitude record of 314,750 feet in July of 1962. For this accomplishment, White was awarded USAF Astronaut Wings.
Bob White flew the X-15 a total of sixteen (16) times. He was one (1) of only twelve (12) men to fly the aircraft. White left X-15 Program and Edwards AFB in 1963. He went on to serve his country in numerous capacities as a member of the Air Force including flying 70 combat missions in Viet Nam. He returned to Edwards AFB as AFFTC Commander in August of 1970.
Major General Robert M. White retired from the United States Air Force in 1981. During his period of military service, he received numerous decorations and awards including the Air Force Cross, Distinguished Service Medal, Silver Star with three oak leaf clusters, Legion of Merit, Distinguished Flying Cross with four oak leaf clusters, Bronze Star Medal, and Air Medal with 16 oak leaf clusters.
Bob White was a true American hero. He was one of those heroes who neither sought nor received much notoreity for his accomplishments. He served his country and the aviation profession well. Bob White’s final flight occurred on Wednesday, 17 March 2010. He was 85 years of age.
Fifty-six years ago this week, the USN/Convair XFY-1 became the first Vertical Take-Off and Landing (VTOL) aircraft to successfully transition from vertical to horizontal flight. The historic flight was piloted by famed Convair engineering test pilot James F. “Skeets” Coleman.
Motivated by World War II lessons-learned, the United States Navy began contemplating the feasibility of using VTOL aircraft for fleet defense in 1947. A VTOL aircraft would combine the vertical take-off and landing capabilities of a helicopter with the speed and agility of a fighter. The operational advantage and flexibility derived from basing such an aircraft on non-aircraft carrier naval vessels were powerful allurements indeed.
In May of 1951, the Navy awarded contracts to Lockheed and Convair to develop and flight test an experimental VTOL aircraft. The Lockheed offering was designated as the XFV-1 while Convair’s version became known as the XFY-1. Both companies were to produce two (2) test aircraft each. History records that each company would ultimately produce just a single copy of its respective prototype.
Convair nicknamed its VTOL aircraft Pogo after the Pogo Stick jumping toy popularized by an earlier generation of American youth. Such appellation referred to the XFY-1’s tendency to bounce on its quartet of shock-absorbered landing gear at touchdown. The similarity to one bouncing up and down on a spring-loaded Pogo Stick is obvious.
The XFY-1 Pogo measured 35 feet in length and had a wing span of nearly 29 feet. The type had a GTOW of 16,250 lbs and an empty weight of 11,750 lbs. Power was provided by a 5,500 hp Allison YT-40 turboprop which drove twin, 3-blade, 16-foot diameter contra-rotating propellers. This propulsion system produced a maximum thrust of 17,000 lbs.
The Pogo was difficult to fly vertically in close proximity to the ground. Prop-wash interaction with the aircraft and ground plane being the chief culprit. Even more difficult was the transition from vertical to horizontal flight and back again. It was particularly challenging to land the aircraft as the pilot had to look over his shoulder and “back down” to a landing.
The XFY-1 pilot sat in a seat that rotated to accommodate vertical and horizontal flight attitudes as appropriate. Pilot cockpit entry was via a 25-foot auxiliary ladder. Interestingly, the pilot was provided with a 25-foot rope for emergency egress during ground operations.
James F. “Skeets” Coleman was Convair’s project test pilot for XFY-1 flight tests. Coleman began tethered flight testing of the aircraft on Thursday, 29 April 1954 at NAS Moffett Field, California. Roughly 60 hours of tethered-flight testing took place within Moffett’s cavernous Hanger Number One. With a ceiling height of 195 feet, the building provided ample room for initial XFY-1 vertical flight testing.
On Sunday, 01 August 1954, Coleman made the first untethered XFY-1 flight test in the vertical. Following several more successful vertical take-off and landing trials, XFY-1 flight test activities were transferred to NAS Brown Field near San Diego, California. There, Coleman intently practiced (making 70 flights overall) in anticipation of the first attempt to transition the XFY-1 from vertical to horizontal flight.
On Tuesday, 02 November 1954, with Skeets Coleman at the controls, the XFY-1 lifted-off in the vertical from Brown Field. Coleman then carefully and skillfully transitioned the XFY-1 to horizontal flight for the first time. In 21 minutes of horizontal flight, Coleman put the nimble XFY-1 through its paces. The Pogo’s big Allison turboprop had power to spare as Coleman hit airspeeds well in excess of 300 mph.
When it was finally time to land the XFY-1, Coleman made a low altitude, minimum power approach and pulled into the vertical. As the aircraft quickly ascended, the airspeed bled-off just as rapidly. Near the top of the climb, Coleman advanced the throttle. The XFY-1 hung in the cool autumn air on the thrust of its twin props alone. The pilot then carefully descended from about 1,000 feet AGL and landed uneventfully.
Skeets Coleman made many more flights in which he demonstrated the Pogo’s VTOL capabilities. However, USN interest in the VTOL concept in general and the XFY-1 aircraft in particular began to wane. While the XFY-1 had indeed demonstrated the feasibility of VTOL flight, it also revealed the operational impracticality of such given the technology of the time.
The Achilles Heel of the Convair XFY-1 VTOL aircraft was the vertical landing phase. The pilot just could not judge rate-of-descent accurately. This was attributed partly to the fact that he had to look over his shoulder throughout the descent. In addition, XFY-1 throttle-induced lateral-directional handling qualities were poor and forced the pilot to work very hard at landing the aircraft even in low-wind conditions.
Skeets Coleman made the last flight of the XFY-1 experimental aircraft on Thursday, 16 June 1955. For his significant piloting efforts in successfully demonstrating the feasibility of the VTOL concept, he received the 1954 Harmon Trophy. The lone Convair XFY-1 Pogo test aircraft survived the flight test program and is currently held in the historical collection of the National Air and Space Museum.
Forty-eight years ago this month, Mercury Astronaut Walter M. Schirra, Jr. orbited the Earth six (6) times in his Mercury spacecraft code-named Sigma 7. The near-perfect 9-hour spaceflight was the United States’ third manned orbital mission flown within a period of eight (8) months.
Project Mercury was United States’ first manned spaceflight program. This historic pioneering space effort helped lay the foundation for America’s quest for the Moon. A total of six (6) missions (2 sub-orbital and 4 orbital) was flown between May of 1961 and May of 1963.
The Mercury Spacecraft measured 11.5 feet in length and had a diameter of 6.2 feet. Orbital weight was roughly 3,000 pounds. With a cockpit volume of only 60 cubic feet, an astronaut’s corporeal fit inside the spacecraft was exceedingly tight. Vehicle entry and egress was a real shoe-horning process. It is not complete hyperbole to say that, once inside, an astronaut wore, more than rode in, the Mercury space vehicle.
Despite its dimunitive size, the Mercury Spacecraft was an able spacefaring ship. Indeed, it was configured with a complete suite of life support, navigation, attitude control, communications, deboost, recovery and thermal protection systems. Aided by a vast national mission support team, recovery force, and world-wide tracking system, the Mercury spaceflight effort was entirely successful in establishing America in space.
America’s first astronauts were known as the Mercury Seven. History records their names; Shepard, Grissom, Glenn, Carpenter, Schirra, Cooper and Slayton. In the tense 1960’s Space Race with the Soviet Union, these men were indeed America’s Single-Combat Warriors immortalized by writer Tom Wolfe in his classic, The Right Stuff.
Mercury-Atlas No. 8 (MA-8) was the fifth Mercury mission. Whereas the two (2) previous flights had been three (3) orbit missions, MA-8 was scheduled to orbit the Earth six (6) times. The focus would be on spacecraft operations instead of space science. The intent was to verify that the Mercury spacecraft could be cleared for an orbital mission duration of at least 24 hours on the very next flight
As was the custom for a Mercury astronaut, Schirra personally named his orbital steed. As such, Schirra chose the name Sigma 7. The term Sigma, the Greek mathematical symbol for summation, signified a summation or culmination of flight experience and engineering development that led to a mature Mercury Spacecraft system. The numeral 7 represented the Mercury Seven.
The MA-8 mission began with lift-off from Cape Canaveral’s LC-14 at 12:15:12 UTC on Wednesday, 03 October 1962. The Atlas D launch vehicle placed Schirra into a 152.8-nm x 86.9-nm orbit. Once in orbit, Schirra quickly got down to business. This included tracking the Atlas booster, maneuvering the spacecraft, observing and photographing the Earth, and conducting various scientific experiments.
Schirra did a particularly good job at conserving the precious supply of Reaction Control System (RCS) fuel. One of the MA-8 objectives had been to do so. In fact, Schirra conserved fuel even more efficiently than planned. Other than an annoying and uncomfortable spacesuit heating problem that occurred several times, the entire MA-8 mission was what Schirra would ultimately call “textbook”.
MA-8 retro-fire occurred at 21:07:12 UTC. During the reentry, the automatic rate stabilization system damped spacecraft pitch and yaw oscillations. Drogue and main parachute deployment took place at 40,000 feet and 15,000 feet, respectively. Splashdown in the Pacific Ocean occurred 1,200 nm northwest of Hawaii at 21:28:22 UTC.
The success of MA-8 paved the way to Gordon Cooper’s historic 22-orbit, 34-hour MA-9 mission in May of 1963. The Gemini and Apollo Programs would soon follow. Wally Schirra would play a big part in both. He commanded the historic Gemini 6 orbital rendezvous mission in December of 1965. Schirra also went on to command the critical Apollo 7 mission in October of 1968.
Wally Schirra was the only member of the Mercury Seven to orbit the Earth in Mercury, Gemini and Apollo spacecraft.
Forty-five years ago this month, the USAF/North American XB-70A Valkyrie reached three times the speed of sound for the first time. The historic aviation achievement took place on the 18th anniversary of the breaking of the sound barrier by the USAF/Vell XS-1.
When it comes to legendary aircraft, aviation enthusiasts speak in almost reverent terms about the XB-70A Valkyrie. Indeed, few aircraft have evoked such utter awe or symbolized better the profound majesty of flight than the “The Great White Bird”. Though its flight history was brief, the XB-70A’s influence on aviation has proven to be of enduring worth.
The Valkyrie measured 185 feet in length, had a wingspan of 105 feet and an empty weight of 210,000 pounds. With a GTOW of 550,000 pounds, it was the heaviest supersonic-capable aircraft of all-time. The aircraft was powered by a six-pack of General Electric YJ93-GE-3 turbojets totaling 172,200 pounds of thrust in afterburner.
To enhance lift-to-drag ratio and directional stability at high Mach number, the Valkyrie was configured with wing tips that could be deflected downward as much as 65 degrees. Each wing tip was the size of an USAF/Convair B-58A Hustler wing panel. To this day, the XB-70A deflectable wing tip is the largest control surface ever used on an aircraft.
The XB-70A was originally intended to be a supersonic strategic bomber. The aircraft’s mission was to penetrate Soviet airspace at Mach 3 and deliver nuclear ordnance from an altitude of 72,000 feet. However, the rapid ascendancy of Soviet surface-to-air missile capability would compromise the type’s military mission before it even flew.
As a consequence of the above, the Valkyrie ultimately became a high-speed flight research aircraft. Only two (2) copies were constructed and flown. Ship No. 1 (S/N 62-0001) made its maiden flight on Monday, 21 September 1964 while Ship No. 2 (62-0207) first took to the air on Saturday, 17 July 1965.
XB-70A Ship No. 1 became the first Valkyrie to hit Mach 3. It did so while flying at an altitude of 70,000 feet on Thursday, 14 October 1965. The flight crew consisted of North American Aviation test pilot Alvin S. White (aircraft commander) and USAF Colonel Joseph Cotton (co-pilot).
The XB-70A aircraft flew all of their flight research missions out of Edwards Air Force Base in California. Between September of 1964 and February of 1969, a total of 129 XB-70A research flights took places; 83 by Ship No. 1 and 46 by Ship No. 2. A total of nearly 253 flight hours was amassed by the aircraft.
The XB-70A Program made significant contributions to high-speed aircraft technology including aerodynamics, aerodynamic heating, flight controls, structures, materials, and air-breathing propulsion. Lessons-learned from its flight research have been applied to numerous aircraft developments including the B-1A, American SST, Concorde and the TU-144.
XB-70A Ship No. 1 survived the flight test program while Ship No. 2 did not. The latter was destroyed in a mid-air collision with a NASA F-104N on Wednesday, 08 June 1966. Today, XB-70A Ship No. 1 can be seen at the National Museum of the United States Air Force at Wright-Patterson Air Force Base in Dayton, Ohio.
Sixty-three years ago this month, the swept-wing XP-86, the initial version of the famed USAF/North America F-86 Sabre, began flight testing at what is now Edwards Air Force Base. The popular Mig Alley legend would be produced in numerous variants and ultimately rack-up a total production run of nearly 10,000 aircraft worldwide.
In the waning days of World War II, the United States Army Air Force (USAAF) issued the requirements for a new high-speed, jet-powered fighter/interceptor aircraft. North American Aviation (NAA) captured the USAAF’s attention with a prototype swept-wing aircraft known as the XP-86. The “X” designation was shorthand for Experimental while the “P” stood for Pursuit.
The XP-86 (later designated as the XF-86 where “F” stood for Fighter) was the first United States fighter to incorporate wing sweep. The key benefit derived from sweeping the wings was to greatly reduce transonic wave drag. Based on aerodynamics data captured from the defeated Third Reich, NAA engineers designed the XF-86 with a wing sweep of 35 degrees.
A drawback to using wing sweep is that low-speed flight characteristics are adversely affected. The principal detrimental effect being a reduction in lift. However, NAA solved this problem by the incorporation of leading edge slats to enhance lift production at low speed.
The XF-86 measured roughly 37-feet both in length and wingspan. Empty weight was some 12,000 lbs. Power was provided by a Chevrolet J35-C-3 turbojet that generated a paltry 3,750 pounds of thrust. Later variants of the Sabre would be powered by jet engines generating nearly 10,000 pounds of thrust.
On Wednesday, 01 October 1947, XF-86 No. 1 took to the air for the first time from Muroc Army Air Field, California. USAAF Major and WW II 16-kill ace George S. “Wheaties” Welch was at the controls of the XF-86. Intestingly, the historical record strongly suggests that Welch exceeded the speed of sound during a dive on that first flight test.
The case of George Welch is an intriguing sub-plot of the F-86 Sabre story. Welch was stationed at Pearl Harbor on 07 December 1941. He was one of the very few American pilots to get in the air and fight the attacking Japanese forces. Numerically overwhelmed, he nontheless splashed four (4) enemy aircraft and lived to fly and fight another day.
Welch served three (3) combat tours in WW II for a total of 348 combat missions. After leaving the service in 1944, he joined North American Aviation as a test pilot. Welch progressed quickly and became NAA’s Chief Test Pilot. This path ultimately led to Welch flight testing the XP-86 Sabre.
Although denied verification in official Air Force records, both oral history and strong circumstantial evidence points to the high likelihood that Welch exceeded Mach 1 at least twice before the Bell XS-1 did so on Tuesday, 14 October 1947.
Incredibly, the first instance of Welch and the XF-86 exceeding Mach 1 was on the occasion of its first flight test! Welch dove the aircraft from 35,000 feet and reportedly generated a weak sonic boom.
The second instance of Mach 1 exceedance reportedly occurred on Tuesday, 14 October 1947. This time Welch dove the XF-86 from 37,000 feet and generated a stronger sonic boom. Apparently, this event took place just before the Bell XS-1, with USAAF Major Charles E. “Chuck” Yeager at the controls, achieved Mach 1.06 later that same morning.
Welch was never officially credited with being the first to achieve supesonic flight. A number of reasons account for this circumstance. First, his aircraft was not instrumented properly to verify flight performance at quasi-supersonic speeds. Additionally, Welch’s aircraft was not tracked by radar.
In addition to the technical reasons cited above, there was political intrigue surrounding Welch’s supersonic dive flights as well. NAA (and thus Welch) had been ordered not to exceed Mach 1 before the rocket-powered Bell XS-1 did so. Perhaps the only concession accorded Welch was that USAF later referred to Yeager’s historic superonic flight as the first time the sound barrier was broken in level flight.
George Welch went on to a distinguished, but all too brief flight test career. On Monday, 25 May 1953, he became the first man to exceed Mach 1 in level flight in a jet-powered production aircraft. That aircraft was the North American F-100 Super Sabre. Welch perished on Tuesday, 12 October 1954 when his YF-100A went out of control and distintegrated during a 7-g pull-up at Mach 1.55.
For its part, the F-86 Sabre ultimately served long and well in the air forces of the United States and a host of other western-friendly nations. Perhaps its greatest claim to fame accrues from the type’s remarkable aerial combat perfromance in the Korean War. Indeed, despite being numerically bested by Soviet-built MIG-15 aircraft, the official record shows that USAF pilots made 792 kills flying the Sabre. Compared with 76 kills made by the opposition, the Sabre registered a phenomenal 10:1 kill ratio.
Twenty-two years ago this week, the Space Shuttle Discovery and its five man crew landed on Rogers Dry Lake at Edwards Air Force Base to successfully complete the Return-to-Flight (RTF) mission of STS-26. The flight signaled a resumption of the Space Shuttle Program after a 32-month hiatus in manned spaceflight resulting from the Challenger disaster.
Well chronicled is the tragic loss of the Space Shuttle Challenger and its crew of seven on Tuesday, 28 January 1986. Following lift-off at 16:38 UTC from Cape Canaveral’s LC-39B, the launch vehicle distintegrated 73 seconds into flight. The presidentially-appointed Rogers Commission concluded that the primary cause was failure of an O-ring seal in a field joint of the right Solid Rocket Booster (SRB).
While the SRB O-ring failure was the physical cause of the Challenger mishap, the Rogers Commission brought to light a more fundamental and disturbing reason for the tragedy. Specifically, the very decision to launch Challenger on that unusally cold January morning in Florida was fundamentally flawed.
As chillingly delineated in Dianne Vaughan’s “The Challenger Launch Decision”, a culture of deviance with respect to Shuttle flight safety issues had slowly developed at NASA. Pressure to launch, scarce resources and organizational disconnects contributed to NASA management’s blind spot when it came to Shuttle flight safety. The SRB contractor was culpable as well and for the same reasons.
Following redesign and testing of the SRB field joints and the implementation of a myriad of other fixes, NASA prepared to return the Shuttle to flight. The mission was designated as STS-26. To the Space Shuttle Discovery would go the honor of and the responsibility for flying the RTF mission. STS-26 was to be a five day orbital mission.
A five-member crew was selected by NASA to fly STS-26. Each crew member had spaceflight experience. You remember their names. Mission Commander Frederick H. “Rick” Hauck, Pilot Richard O. Covey, and Mission Specialists John M. “Mike” Lounge, George D. “Pinky” Nelson and David C. Hilmers.
Discovery and her brave crew lifted-off from at 15:37 UTC on Thursday, 29 September 1988 from the very same location that Challenger did; LC-39B at Cape Canaveral, Florida. Millions watched that day. Some were in the big crowds that formed in and around the Cape complex. Most observed the event on television. Many prayed.
All who watched Discovery lift-off that day remembered the previous Shuttle flight. Indeed, they remembered what happened just after the CAPCOM’s call: “Challenger, go at throttle-up.” (Ironically, Richard Covey was the CAPCOM who made that very call.) Today, they heard a similar call over the Shuttle communications network: “Discovery, go at throttle-up.” A collective breath was held. After throttle-up, Discovery continued all the way to orbit. YES!!!
The mission itself seemed to be anti-climatic. A Tracking and Data Relay Satellite (TDRS) was deployed from Discovery’s payload bay to replace the one lost in the Challenger explosion. A multitude of space experiments was conducted by the crew. Fairly standard stuff. Only deboost, the rigors of reentry and the typical dead-stick landing lay ahead.
Discovery landed on Runway 17 at Edwards Air Force Base on Monday, 03 October 1988. Main gear touchdown occurred at 16:37 UTC. Approximately, 450,000 American’s witnessed Discovery’s landing in person. A few who did had witnessed its launch in person as well.
The emotion that attended Discovery’s landing in October 1988 was simply overwhelming. Indeed, the experience was an integral part of the healing process for a Nation that still grieved the loss of Challenger and her crew. A Time magazine cover page headline the following week excitedly read: “Whew! America Returns to Space” And indeed it had.
Forty-four years ago this month, Gemini 11 flew a spectacular 3-day mission that helped pave the way to the first manned lunar landing. The all-Navy crew included astronauts Charles P. Conrad, Jr. and Richard F. Gordon, Jr.
America’s manned space effort of the 1960’s and early 1970’s consisted of the Mercury, Gemini and Apollo Programs. Mercury put the first Americans into space and gave the country a basic manned spaceflight capability. Apollo put Americans on the Moon and returned them safely to the Earth. Gemini was the bridge. Without it, the United States could not have achieved the national goal of landing men on the Moon before the end of the 1960’s.
The Gemini Program consisted of ten (10) manned spaceflights that were flown between March of 1965 and December 1966. Gemini 11 was the penultimate mission. Its primary goals included performing a direct ascent rendezvous, increasing its orbital altitude by more than 500 NM, using tethered flight to produce artificial gravity, conducting several space walks and performing a computer-controlled precision landing.
Gemini 11 lifted-off from Cape Canaveral’s LC-19 at 14:42:26 UTC on Monday, 12 September 1966. The initial orbit was 151-NM (apogee) by 87-NM (perigee). Relying on radar and a primitive flight computer, it took Conrad and Gordon about 85 minutes to successfully perform history’s first direct ascent or first-orbit rendezvous. Their target was an Agena Target Vehicle (GATV-11) which had been launched 90 minutes prior to Gemini 11’s lift-off.
Approximately 24 hours into the Gemini 11 mission, Gordon initiated the first of two planned Extra Vehicular Activities (EVA’s). His first task was to connect a 100-foot tether between the Gemini and Agena spacecraft. While he did so successfully, Gordon was exhausted from the effort. He perspired so heavily that his helmet face plate fogged-over. The remainder of the EVA was cancelled when Conrad commanded Gordon to return to the Gemini.
At a mission elapsed time of about 40.5 hours, the Gemini 11 crew fired-up the Agena’s rocket engine for a 25 second burn. This action increased the apogee of the Gemini-Agena stack to a record altitude of 739 NM. Following two (2) highly-elliptical orbits, the Agena’s rocket engine was once again ignited. The result of this rocket engine burn was to lower the spacecraft and its crew to a near-circular 164 NM x 155 NM orbit.
Roughly 46 hours into the mission, Gordon conducted a second EVA. This time Gordon would simply stand-up in his seat and conduct several hours of photographic experiments. Doing so was not physically-taxing and Gordon’s efforts were entirely successful.
Following successful completion of the second EVA, the Gemini undocked from the ATV. With the spacecraft still connected by the 100-foot tether, the crew used the Gemini’s thrusters to establish a slow rotation of the pair until the tether became taut. The idea was to induce a small artificial gravity between the rotating spacecraft. Keeping the tether taut was not easy. While this was another first for Gemini, the maximum artificial gravity induced was a paltry 0.00015-g.
Upon completion of the tethered-flight experiment, the tether connecting Gemini 11 and the GATV-11 was released at a mission elapsed time of about 51 hours. The Gemini 11 crew performed additional spacecraft manuevers and conducted a variety of spaceflight experiments over the next 19 hours. However, Gemini 11 had one more historic space-first to accomplish before mission’s end.
As the 70th hour of flight neared completion, the crew fired the Gemini 11 retro rocket system to begin their return to Earth. For the first time, a Gemini crew would allow a computer to control the reentry. A so-called “hands-off” reentry. All previous Gemini reentries were manually controlled by the command pilot.
Gemini 11 splashed-down in the western Atlantic Ocean at 13:59:35 UTC on Thursday, 15 September 1966. The computer did a pretty good job of controlling the reentry too. The spacecraft landed within 2.4 NM of the USS Guam; only 1.3 NM off target. The accurate landing allowed recovery of, first the crew, then the spacecraft, aboard the Guam within an hour of landing. Mission total elapsed time was 71 hours, 17 minutes and 8 seconds.
For their significant efforts on Gemini 11, the crew of Conrad and Gordon would eventually fly to the Moon during the Apollo Program. Indeed, Pete Conrad was the Commander of Apollo 12 and the third American to walk on the Moon. (Alan Bean was the Apollo 12 Lunar Module Pilot and the fourth man to walk the lunar surface. ) Conrad’s Command Module Pilot was none other than his good friend and Gemini 11 co-pilot Richard Gordon.
Fifty-four years ago this month, the USAF/North American F-107A aircraft flew for the first time. The Mach 2-capable fighter-bomber went supersonic on the type’s maiden flight.
The F-107A was designed, developed and tested by North American Aviation (NAA) in the mid-1950’s. With it, the contractor hoped to satisfy Tactical Air Command’s (TAC) need for a front line fighter-bomber. However, Republic Aircraft also had a candidate for the same role; the F-105 Thunder Chief.
The competition between Republic and North American for the TAC fighter-bomber production contract has a story of its own. Suffice it to say here that the competitive effort was (1) extremely close and (2) tinged with political intrigue. In the end, Republic Aircraft reaped the spoils of victory.
Although the F-107A came out on the short end of the stick in the TAC fighter-bomber competition, such did not imply an inferiority in fulfilling the intended role. Indeed, like the Northtrop YF-23’s loss to the General Dynamics YF-22 in the ATF competition of the early 1990’s, North American’s failure to get the nod with the F-107A is still a subject of passionate debate.
The F-107A measured 60.8 feet in length and had a wing span of 36.6 feet. Gross take-off weight was around 41,000 pounds. The aircraft was powered by a single Pratt and Whitney YJ75-P-11 turbojet that produced 15,500 pounds of thrust in military power and 23,500 pounds of thrust in full afterburner.
F-107A longitudinal control was provided by an all-flying horizontal tail. Similarly, an all-flying vertical tail was employed for directional control. Lateral control was provided by a unique 3-segment spoiler-deflector system mounted on each wing. The aircraft was also configured with inboard flaps and leading edge slats for lift augmentation at low speeds.
A unique and prominent feature of the F-107A was its dorsal-mounted air induction system known as the Variable-Area Inlet Duct (VAID). Internally, this unit incorporated a system of adjustable ramps to efficiently decelerate and compress freestream prior to entering the engine compressor face. Ramp deflection scheduling with Mach number was controlled automatically. Ramp boundary layer bleed air was vented from the top of the VAID.
The F-107A carried weapons externally. In addition to wing pylon-mounted stores, the aircraft was designed to carry a single “special weapon” from a semi-submerged recess located on the aircraft ventral centerline. The term “special weapon” means that it was a tactical nuclear bomb. The Sandia-developed store could also be used in combination with a special saddle fuel tank to extend aircraft range.
A total of three (3) F-107A aircraft were built and flown. USAF-assigned tail numbers include 55-5118, 55-5119 and 55-5120. On Monday, 10 September 1956, the No. 1 ship (55-5118) took-off from Edwards Air Force Base on its first flight. NAA Chief Test Pilot Robert Baker, Jr. was at the controls. The aircraft attained a maximum Mach number of 1.03 in a 43 minute flight test.
The F-107A could really scream. The type had a maximum climb rate of around 40,000 feet per minute in full afterburner. The max demonstrated Mach number attained by the F-107A was Mach 2.18. Program engineers estimated that by increasing the inlet area slightly, the F-107A was capable of reaching roughly Mach 2.4.
The trio of F-107A aircraft flew 272 flight tests totalling 176.5 hours. Included in this testing was successful separation of a special store prototype at Mach 2. Test pilots of note who flew the F-107A included XB-70A pilot Al White and X-15 pilots Scott Crossfield, Bob White, Jack McKay and Forrest Peterson.
Though it never became a production aircraft, the F-107A contributed in significant ways to aviation progress. Indeed, many future aircraft would greatly benefit from F-107A flight control and air induction technology including the A-5 Vigilante, XB-70A, A-12, SR-71, YF-12A and F-15.
The F-107A was the last of NAA’s fighter aircraft which includes such notables as the P-51 Mustang, the F-86 Sabre and the F-100 Super Sabre. While the F-107A has often been referred to in print as the Ultra Sabre, Ultimate Sabre, Super Super Sabre or such, it was never officially assigned a nickname. Alas, there was never an XF-107A or YF-107A designation either. North American Aviation’s TAC fighter-bomber candidate was simply known as the F-107A.
Today, the No. 1 F-107A (55-5118) is displayed at the Pima Air and Space Museum (PASM) in Tucson, Arizona. The No. 2 ship (55-5119) resides at the USAF Museum at Wright-Patterson Air Force Base in Dayton, Ohio. The No. 3 airplane (55-5120) no longer exists as it was relegated to the status of a fire fighting prop and ultimately destroyed in that role sometime in 1961 or 1962.
Twenty-five years ago today, the USAF/LTV ASM-135 anti-satellite missile successfully intercepted a target satellite orbiting 300 nautical miles above the Earth. The test was the first and only time that an aircraft-launched missile successfully engaged and destroyed an orbiting spacecraft.
The United States began testing anti-satellite missiles in the late 1950’s. These and subsequent vehicles used nuclear warheads to destroy orbiting satellites. A serious disadvantage of this approach was that a nuclear detonation intended to destroy an adversary satellite will likely damage nearby friendly satellites as well.
By the mid 1970’s, the favored anti-satellite (ASAT) approach had changed from nuclear detonation to kinetic kill. This latter approach required the interceptor to directly hit the target. The 15,000-mph closing velocity provided enough kinetic energy to totally destroy the target. Thus, no warhead was required.
The decision to proceed with development and deployment of a US kinetic kill weapon was made by President Jimmy Carter in 1978. Carter’s decision came in the aftermath of the Soviet Union’s successful demonstration of an orbital anti-satellite system.
LTV Aerospace was awarded a contract in 1979 to develop the Air-Launched Miniature Vehicle (ALMV) for the USAF. The resulting anti-satellite missile (ASM) system was designated the ASM-135. The two-stage missile was to be air-launched by a USAF F-15A Eagle executing a zoom climb. In essence, the aircraft acted as the first stage of what was effectively a 3-stage vehicle.
The ASM-135 was 18-feet in length and 20-inches diameter. The 2,600-lb vehicle was launched from the centerline station of the host aircraft. The ASM consisted of a Boeing SRAM first stage and an LTV Altair 3 second stage. The vehicle’s payload was a 30-lb kinetic kill weapon known as the Miniature Homing Vehicle (MHV).
The ASM-135 was first tested in flight on Saturday, 21 January 1984. While successful, the missile did not carry a MHV. On Tuesday, 13 November 1984, a second ASM-135 test took place. Unfortunately, the missile failed when the MHV that it was carrying was aimed at a star that served as a virtual target. Engineers went to work to make the needed fixes.
In August of 1985, a decision was made by President Ronald Reagan to launch the next ASM-135 missile against an orbiting US satellite. The Solwind P78-1 satellite would serve as the target. Congress was subsequently notified by the Executive Branch regarding the intended mission.
The historic satellite takedown mission occurred on Friday, 13 September 1985. USAF F-15A (S/N 77-0084), stationed at Edwards Air Force Base, California and code-named Celestial Eagle, departed nearby Vandenberg Air Force Base carrying the ASM-135 test package. Major Wilbert D. Pearson was at the controls of the Celestial Eagle.
Flying over the Pacific Ocean at Mach 1.22, Pearson executed a 3.8-g pull to achieve a 65-degree inertial pitch angle in a zoom climb. As the aircraft passed through 38,000-feet at Mach 0.93, the ASM-135 was launched at a point 200 miles west of Vandenberg. Both stages fired properly and the MHV intercepted the Solwind P78-1 satellite within 6-inches of the aim point. The 2,000-lb satellite was obliterated.
In the aftermath of the stunningly successful takedown of the Solwind P78-1 satellite, USAF was primed to continue testing the ASM-135 and then introduce it into the inventory. Plans called for upwards of 112 ASM-135 rounds to be flown on F-15A aircraft stationed at McChord AFB in Washington state and Langley AFB in Virginia. However, such was not to be.
Even before the vehicle flew, the United States Congress acted to increasingly restrict the ASM-135 effort. A ban on using the ASM-135 against a space target was put into effect in December 1985. Although USAF actually conducted successful additional ASM-135 flight tests against celestial virtual targets in 1986, the death knell for the program had been sounded.
In the final analysis, a combination of US-Soviet treaty concerns, tepid USAF support and escalating costs killed the ASM-135 anti-satellite effort. The Reagan Administration formally cancelled the program in 1988.
While the ASM-135 effort was relatively short-lived, the technology that it spawned has propagated to similar applications. Indeed, today’s premier exoatmospheric hit-to-kill interceptor, the United States Navy SM-3 Block IA anti-ballistic missile, is a beneficiary of ASM-135 homing guidance, intercept trajectory and kinetic kill technologies.
Thirty-three years ago this week, the Voyager 1 space probe was launched on a first-ever mission to fly past the planets Jupiter and Saturn. Incredibly, both Voyager 1 and its companion Voyager 2 spacecraft continue to function quite well and transmit valuable data back to Earth as they voyage eternally in deep space.
The Voyager Program was a 1970’s NASA project to investigate the giant gas planets Jupiter and Saturn. Two (2) Voyager spacecraft were launched in the summer of 1977. Each probe was extensively instrumented to measure the planetary and space environments that they would encounter. Design lifetime was 5 years.
Due to a unique alignment of Jupiter, Saturn, Uranus and Neptune that occurs every 175 years, the Voyager Program had the potential to be much more than a two-planet journey. Specifically, a gravity assist at each planet could bend Voyager’s trajectory and send it to the next outermost planet in what was termed a Grand Tour of the Solar System’s giant gas planets.
And yet there was even more potential for scientific investigation beyond the Grand Tour! Given that either or both of the Voyagers continued to operate well beyond its/their design liftetime, the opportunity to investigate interstellar space itself would be a real possibility.
Voyager 1 was launched from Cape Canaveral’s LC-41 at 12:56:00 UTC on Monday, 05 September 1977. A Titan IIIE-Centaur launch vehicle provided the energy required to send the 1,588-pound spacecraft on its deep space mission. Interestingly, Voyager 1 launch delays resulted in Voyager 2 being launched several weeks earlier (i.e., Saturday, 20 August 1977).
Each Voyager spacecraft carries a 12-inch gold-plated copper record that includes terrestrial sights and sounds as well as a variety of human speech. The intent of carrying this record is to provide the finder, ostensibly the inhabitant of another celestial world, with information about and the location of our home planet.
Voyager 1’s quicker trajectory allowed it to arrive at Jupiter (05 March 1979) prior to the arrival of Voyager 2 (09 July 1979). Voyager 1 would proceed to flyby Saturn on 12 November 1980. Voyager 2 would fly the actual Grand Tour mission by visiting Jupiter, Saturn, Uranus and Neptune. This last encounter occurring on 25 August 1989.
As historic and momentous as was the completion of Voyager’s primary and extended planetary missions, there was more in store for the twin probes. Twelve (12) years after departing Earth, both spacecraft were operating amazingly well as they headed out of the Solar System. As a result, NASA established the Voyager Interstellar Mission (VIM).
The VIM is a tri-phase investigatory effort consisting of exploration of the Sun’s termination shock and heliosheath as well as the interstellar medium itself. Voyager 1 crossed the termination shock in December of 2004 at a distance of 8.74 billion miles from Earth. Voyager 2 achieved the same milestone in August of 2007 when it was 7.81 billion miles from Earth.
Both Voyager spacecraft are currently investigating the Sun’s heliosheath. Each is still sending back scientific data. Current estimates show that Voyager 1 and 2 will continue to function through at least 2025. The hope is that at least one of the spacecraft will have entered and probed interstellar space by that time.
Meanwhile, both Voyagers soldier-on at a Sun departure rate of 335 mllion miles per year for Voyager 1 and 307 million miles per year for Voyager 2. As of this writing, Voyager 1 is more than 10.66 billion miles from Earth, making it the most distant man-made object ever sent from Earth.
Forty-five years ago this month, NASA astronauts Leroy Gordon Cooper and Charles M. “Pete” Conrad set a new spaceflight endurance record during the flight of Gemini 5. It was the third of ten (10) missions in the historic Gemini spaceflight series. The motto for the mission was “Eight Days or Bust”.
The purpose of Project Gemini was to develop and flight-prove a myriad of technologies required to get to the Moon. Those technologies included spacecraft power systems, rendezvous and docking, orbital maneuvering, long duration spaceflight and extravehicular activity.
The Gemini spacecraft weighed 8,500 pounds at lift-off and measured 18.6 feet in length. Gemini consisted of a reentry module (RM), an adapter module (AM) and an equipment module (EM).
The crew occupied the RM which also contained navigation, communication, telemetry, electrical and reentry reaction control systems. The AM contained maneuver thrusters and the deboost rocket system. The EM included the spacecraft orbit attitude control thrusters and the fuel cell system. Both the AM and EM were used in orbit only and discarded prior to entry.
Gemini-Titan V (GT-5) lifted-off at 13:59:59 UTC from LC-19 at Cape Canaveral, Florida on Saturday, 21 August 1965. The two-stage Titan II launch vehicle placed Gemini 5 into a 189 nautical mile x 87 nautical mile elliptical orbit.
A primary purpose of the Gemini 5 mission was to stay in orbit at least eight (8) days. This was the minimum time it would take to fly to the Moon, land and return to the Earth. Other goals of the Gemini 5 mission were to test the first fuel cells, deploy and rendezvous with a special rendezvous pod and conduct a variety of medical experiments.
Despite fuel cell problems, electrical system anomalies, reaction control system issues and the cancellation of various experiments, Gemini 5 was able to meet the goal of an 8-day flight. But it wasn’t easy. The last days of the mission were especially demanding since the crew didn’t have much to do. Pete Conrad called his Gemini 5 experience “8 days in a garbage can.”
On Sunday, 29 August 1965, Gemini 5 splashed-down in the Atlantic Ocean at 12:55:13 UTC. Mission elapsed time was 7 days, 22 hours, 55 minutes and 13 seconds. A new spaceflight endurance record.
Gemini 5 was Gordon Cooper’s last spaceflight. Cooper left NASA due to a deteriorating relationship with management. Pete Conrad flew three (3) more times in space. In particular, he commanded the Gemini 11, Apollo 12 and Skylab I missions. Indeed, Conrad’s Apollo 12 experience made him the third man to walk on the Moon.
Thirty-five years ago this month, the USAF/NASA/Martin X-24B became the first lifting body to make an unpowered precision landing on a concrete runway. The feat was pivotal to convincing NASA officials that landing the Space Shuttle Orbiter in an unpowered state was operationally feasible.
Early Space Shuttle Orbiter operational concepts featured the use of a pair of turbojets to provide a powered landing capability. These engines were to be internally stowed just below the Orbital Maneuvering System (OMS) pods. They would be deployed and started once the Orbiter had decelerated to high subsonic speeds.
While airbreathing propulsion would give the Orbiter a loiter and go-around capability, the drawbacks were significant. Jet fuel would have to be carried into and out of orbit. The weight of this fuel and the turbojets would penalize Orbiter payload capability. The system would also increase complexity and cost to Shuttle operations.
As the Shuttle Program grappled with the development of a powered landing capability for the Orbiter, the NASA DFRC flight test community made what appeared to be a rather bold claim. The Orbiter could simply glide all the way to touchdown and land deadstick. After all, X-planes had been doing so safely and without incident since the late 1940’s.
A leading proponent of unpowered Shuttle landings was NASA DFRC test pilot John Manke. He was convinced that the Orbiter could routinely and safely conduct unpowered precision landings on a concrete runway. If true, the Orbiter could land anywhere a 15,000-foot concrete runway was located.
Manke proposed that the X-24B (S/N 66-13551) lifting body be employed to conduct unpowered precision landings on Runway 04/22 at Edwards Air Force Base. He and fellow test pilot USAF Lt. Col. Michael V. Love practiced low lift-to-drag precision landings using F-104 and T-38 aircraft in preparation for the demonstrations.
On Tuesday, 05 August 1975, John Manke successfully made the first-ever unpowered precision landing of an aircraft on a concrete runway. The X-24B main gear touched-down exactly at the aimpoint situated 5,000 feet down Runway 04/22. On Wednesday, 20 August 1975, Mike Love duplicated the feat.
Following the successful unpowered precision landings with the X-24B lifting body, John Manke was quoted as saying: “We now know that concrete runway landings are operationally feasible and that touchdown accuracies of ±500 feet can be expected.” NASA Space Shuttle Program management concurred and officially adopted the unpowered precision landing concept.
Nearly thirty years of Orbiter flight operations have confirmed the wisdom of that long-ago decision.
Fifty-seven years ago this week, the USN/Douglas D-558-II Skyrocket soared to an unofficial world record altitude of 83,235 feet. The Skyrocket’s record altitude mission was piloted by USMC test pilot and World War II triple-ace Lieutenant Colonel Marion E. Carl.
The D-558-II was a United States Navy (USN) X-aircraft and first flew in February of 1948. It was contemporaneous with the USAF/Bell XS-1. The aircraft measured 42 feet in length with a wing span of 25 feet. Maximum take-off weight was 15,266 pounds. Douglas manufactured a trio of D-558-II aircraft (Bureau No.’s 37973, 37974 and 37975).
The original version of the swept-wing D-558-II had both rocket and turbojet propulsion. The latter system provided a ground take-off capability. However, like other early X-aircraft such as the XS-1, X-1A, X-2 and X-15), the D-558-II achieved max performance through the use of a mothership and rocket power alone.
On Friday, 21 August 1953, D-558-II (Bureau No. 37974; NACA 144) was carried to a drop altitude of approximately 30,000 feet over Edwards Air Force Base by a USN P2B-1S launch aircraft. Following drop, Carl fired his LR-8 rocket motor and executed a pull-up in an effort to extract maximum altitude from the D-558-II. Carl hit a maximum Mach number of 1.728 and exceeded the existing altitude by about 3,800 feet.
Flying the D-558-II to altitudes beyond 65,000 feet required Carl to wear a full-pressure suit. The versions available to test pilots in the early 1950’s were crude by today’s standards. They were extremely uncomfortable and very confining. The pilot had to use reverse breathing to supply adequate oxygen to the lungs.
Reverse breathing involves the inhalation of air under pressure wherein oxygen is forced into the lungs by simply opening the mouth. One then has to make a conscious effort to exhale against that pressure in order rid the lungs of carbon dioxide. This unnatural breathing process had to be practiced by a pilot until it became second nature.
Flying the D-558-II (and other 1950’s high-speed research aircraft such as the X-1, X-1A and X-2) to extreme altitude was a sporty proposition. These aircraft exhibited disturbing lateral-directional control characteristics at low dynamic pressure. None of the early X-planes were configured with a 3-axis reaction control system. Control had to be maintained solely by aerodynamic means.
Marion Carl’s altitude mark in the D-558-II would stand until September of 1956 when USAF Captain Iven Kincheloe flew the USAF/Bell X-2 to an altitude of 126,000 feet. Today, the record-setting D-558-II (NACA 144) is displayed at the National Air and Space Museum in our Nation’s capital.
Marion Carl went on to serve his country until he retired from the Marine Corps in 1973 after having attained the rank of Major General. Sadly, Carl was shot to death in 1998 at the age of 82 as he defended his wife Edna from a home invader. A true American hero, Marion E. Carl was buried with full military honors at Arlington National Cemetery.
Fifty years ago this week, the United States successfully launched the Echo 1A passive communications satellite into Earth orbit. The 100-foot diameter balloon was among the largest objects ever to orbit the Earth.
A plethora of earth-orbiting communication satellites provide for a global connectivity that is commonplace today. Such was not always the case. Roll the clock back a half-century and we find that a global communications satellite system was just a concept. However, keen minds would soon go to work and provide mankind with yet another tangible spaceage benefit.
Communications satellites are basically of two types; passive and active. A passive communications satellite (PCS) simply reflects signals sent to it from a point on Earth to other points on the globe. An active communications satellite (ACS) can receive, store, modify and/or transmit Earth-based signals.
The earliest idea for a PCS involved the use of an orbiting spherical balloon. The balloon was fabricated from mylar polyester having a thickness of a mere 0.5 mil. The uninflated balloon was packed tightly into a small volume and inserted into a payload canister preparatory to launch. Once in orbit, the balloon was released and then inflated to a diameter of 100 feet.
The system described above materialized in the late 1950’s as Project Echo. The Project Echo satellite was essentially a huge spherical reflector for transcontinental and intercontinental telephone, radio and television signals. The satellite was configured with several transmitters for tracking and telemetry purposes. Power was provided by an array of nickel-cadmium batteries that were charged via solar cells.
Echo 1 was launched from Cape Canaveral, Florida on Friday, 13 May 1960. However, the launch vehicle failed and Echo 1 never achieved orbit. Echo 1A (sometimes referred to as Echo 1) lifted-off from Cape Canveral’s LC-17A at 0939 UTC on Friday, 12 August 1960. The Thor Delta launch vehicle successfully placed the 166-lb satellite into a 820-nm x 911-nm orbit.
An interesting characteristic of the Echo satellite was the large oscillation in the perigee of its orbit (485 nm to 811 nm) over several months. This was caused by the influences of solar radiation and variations in atmospheric density. While these factors are just part of the earth-orbital environment, their effects were much more noticeable for Echo due to the type’s large surface area-to-weight ratio.
Echo 1A orbited the Earth until it reentered the Earth’s atmosphere on Saturday, 25 May 1968. Echo 2 was a larger and improved version of Echo 1A. It measured 135-feet in diameter and weighed 547-lb. Echo 2 orbited the Earth between January of 1964 and June of 1969. Other than the Moon, both satellites were the brightest objects observable in the night sky due to their high reflectivity.
The Echo satellites served their function admirably. For a time, they were quite a novelty. However, progress on the ACS scene quickly relegated the PCS to obselescence. Today, virtually all communication satellites are of the ACS variety.
Fifty-two years ago today, an Atlas B flew 2,500 miles down the Eastern Test Range in a key developmental test of America’s first Intercontinental Ballistic Missile (ICBM). Among other historic achievements, the test marked the first successful flight of the innovative stage-and-a-half missile.
The infamous Cold War between the United States and the Soviet Union was marked by the specter of nuclear confrontation. Each side developed a family of launch vehicles that could deliver nuclear ordnance to the homeland of the other. The type of launch vehicle employed is known as an Intercontinental Ballistic Missile (ICBM).
An ICBM flies a long, arcing (sub-orbital) trajectory to the target. This flight path is parabolic in shape and thousands of miles in range. The maximum altitude point (apogee) is about mid-way to the target and is located hundreds of miles above the surface of the Earth. An ICBM can reach any point on the globe within 30 minutes of launch.
The first ICBM developed by the United States was the Atlas missile. The origins of this program date back to late 1945 when the United States Army requested proposals from the aerospace industry for novel long-range missile concepts. Consolidated-Vultee Aircraft (Convair) caught the Army’s eye with a missile design that ultimately became the Atlas.
The Atlas was innovative from a number of standpoints. Perhaps most novel was the use of very thin stainless steel tankage in an effort to provide the Atlas with an extremely lightweight structure. However, the tank was so thin that a screwdriver could easily puncture its walls. Moreover, the tank would collapse even under its own weight. Nitrogen pressurization was employed to obtain the necessary structural rigidity.
Another Atlas innovation involved the use of the so-called stage-and-a-half or parallel staging propulsion concept. This system was comprised of a pair of outboard boosters (Stage 0) and a single sustainer core (Stage 1). These engines burned a LOX/kerosene propellant mix and were ignited at launch. Stage 0 was jettisoned after 135 seconds of flight. The sustainer continued to fire an additional 95 seconds.
Atlas A was first flown in June of 1957. The type operated the booster engines only and carried a mass simulator warhead. Only three (3) of its eight (8) developmental flight tests were considered successful. The type achieved a maximum range of 600 nm during its third flight which occurred on Tuesday, 17 December 1957.
Atlas B was the first Atlas test vehicle to operate both the booster and sustainer rocket engines. The vehicle measured 85 feet in length and had a diameter of 10 feet. Lift-off weight was slightly over 244,000 pounds. Its XLR89-5 booster engines and XLR105-5 sustainer engine generated 341,130 and 81,655 pounds of vacuum thrust, respectively.
Atlas B test vehicles flew ten (10) times and enjoyed seven (7) successful flight tests. The first launch (Atlas B, Serial No. 3B) occurred on Friday, 19 July 1958 and was not successful. Atlas B, Serial No. 4B lifted-off from Cape Canaveral’s LC-13 at 22:16 UTC on Saturday, 02 August 1958. This test was entirely successful as the missile reached an apogee of 560 miles and traveled 2,500 miles downrange.
In the years that followed, other Atlas variants were developed including the Atlas C, D, E, F, G and H. Atlas C was the first pre-production version of the Atlas Program. Atlas D was the first operational version of the Atlas ICBM. Atlas E and Atlas F missiles were the first ICBM’s stored in underground silos and raised to ground level for launch. Atlas G and H launched numerous space exploration payloads.
Ironically, the Atlas did not serve long in its primary role as an ICBM. The type was quickly eclipsed by more capable launch vehicles such as the Titan II. However, the Atlas would be used to great effect as a launch vehicle for a wide variety of satellites and scientific spacecraft. The Atlas was ultimately man-rated as a booster. It was used to successfully orbit Mercury astronauts during four (4) Mercury missions flown in 1962 and 1963.
The Atlas has continued to evolve as a commercial launch platform to the current day. The Atlas I was introduced in July of 1990. It was followed by the Atlas II and Atlas III in 1991 and 2000, respectively. The Atlas V is the most recent Atlas variant and first flew in 2002. Significantly, the Atlas is the longest running launch vehicle program in the history of American spaceflight.
Forty-seven years ago today, the United States successfully orbited the world’s first geosynchronous communications satellite. This accomplishment marked the advent of today’s massive global communications market.
A geosynchronous orbit is one in which the orbital period of a satellite is equal to the time it takes the Earth to complete one revolution about its rotational axis. That is, the satellite completes one revolution around the Earth in slightly less than 24 hours. The altitude for such an orbit is 22,300 miles.
A geostationary orbit is a geosynchronous orbit that lies in the Earth’s equatorial plane. A peculiarity of a geostationary orbit is that the satellite’s position above the Earth remains fixed. Three (3) satellites equally spaced around the Earth in geostationary orbit are within direct line-of-sight of each other. Earth-based stations can use this arrangement to relay radio, television and other signals to any point on the globe.
The Hughes Aircraft Company in California began working on a concept for a geosynchronous satellite in early 1959. A trio of Hughes engineers (Harold Rosen, Thomas Hudspeth and Donald Williams) ultimately came up with a workable geosynchronous satellite design. It became known as Syncom – Synchronous Communications Satellite.
Syncom was cylindrical in shape. It measured 28 inches in diameter and had a height of 15.35 inches. The satellite weighed about 150 pounds fully fueled. Syncom’s external surface was covered with solar cells for power generation with nickel-cadmium batteries used for power storage. Syncom was spun about its symmetry axis for stabilization. Attitude control was provided by an array of nitrogen thrusters.
Syncom 1 was launched on Thursday, 14 February 1963 from Cape Canaveral, Florida. Unfortunately, the spacecraft’s signal was lost during the final boost to geosynchronous orbit. The loss of signal was attributed to an electrical failure. Later, ground-based telescope observations confirmed that the satellite had achieved a near-geosynchronous orbit.
Syncom 2 was launched from Cape Canaveral’s LC-17A at 14:38 UTC on Friday, 26 July 1963. A NASA Thor-Delta B provided the ride into orbit. Syncom’s 1,000-pound thrust apogee motor was used for the final ascent to a quasi-geosynchronous orbit. Over a period of several weeks, the satellite was nudged into a true geosynchronous orbit.
Syncom 2’s geosynchronous orbit was inclined 33 degrees with respect to the Earth’s equator. Thus, the resulting orbit was not geostationary. Coupled with the Earth’s rotation, the spacecraft actually moved in a figure-8 pattern over the globe that tracked 33 degrees north and south of the equator.
Syncom 2 went into active service on Friday, 16 August 1963. The satellite went on to perform brilliantly in its intended role as a communications link. A companion satellite, Syncom 3, was launched on Monday, 19 August 1964 and subsequently joined Syncom 2 in geosynchronous orbit. Significantly, Syncom 3 was used to broadcast the 1964 Tokyo Summer Olympics to America.
Syncom 2 and 3 continued to provide intercontinental communications across the Pacific Ocean until 1966. Increasingly more sophisticated and capable satellites followed. The communications revolution that Syncom started has grown to the point where there are now several hundred communications satellites operating in geosynchronous orbit about the Earth. While long silent, Syncom 2 and 3 continue to orbit the Earth today.
Fifty-three years ago today, the United States successfully conducted the only live-fire test of the only known nuclear-armed air-to-air missile ever developed by the West. The test took place over the Nuclear Test Site located at Yucca Flats, Nevada.
The Cold War between the Soviet Union and the United States gave rise to the development of myriad nuclear weapons. Both superpowers ultimately relied on a triad of platforms, consisting of bombers, missiles and submarines, to deliver nuclear ordnance. Each side used these same types of platforms in a defensive role as well.
The United States employed land-based interceptor aircraft for defending against the Soviet bomber threat. These aircraft would go out to engage and destroy Soviet bomber groups before the latter could penetrate US airspace. The weapon of choice for taking out the bombers was the air-to-air missile.
The most fearsome of air-to-air missiles was armed with a nuclear warhead. The idea was simple. A defending aircraft would fire the nuclear-armed missile into a bevy of Soviet bombers. Detonation of the warhead would in theory destroy an entire bomber group with a single atomic blast.
The Douglas Aircraft Company produced just such a missile for the United States Air Force in the mid-1950’s. The subject missile was originally known as the MB-1 Genie (aka Bird Dog, Ding-Dong, and High Card). The type’s 1.5 kiloton nuclear device had a blast radius on the order of 1,000 feet.
The Genie measured 9.67 feet in length and had a nominal diameter of 17.5 inches. Firing weight was 822 pounds. Genie’s Thiokol SR49-TC-1 solid rocket motor had a rated thrust of 36,500 pounds. The resulting high thrust-to-weight ratio allowed the missile to quickly accelerate to the target. Genie had a top Mach number of 3.3 and a range of slightly over 6 miles.
Genie was carried by the top USAF interceptor aircraft of its day; the Northrop F-89 Scorpion, McDonnell F-101B VooDoo and Convair F-106 Delta Dart. The missile was unguided. That is, Genie was simply a point and shoot weapon. The warhead would detonate only after rocket motor burnout. This delay permitted the carrier aircraft to quickly depart the area following launch.
The only in-flight detonation of a Genie warhead occurred during the summer of 1957 as part of Operation Plumbbob. This program was series of nuclear weapons tests conducted from May to October of the subject year at the Yucca Flats Nuclear Test Site in Nevada.
At 1400 UTC on Friday, 19 July 1957, USAF Captain Eric Hutchison fired a single Genie missile from his Northrop F-89J aircraft. The missile’s W25 warhead detonated at 15,000 feet above ground level shortly after rocket motor burnout. A group of USAF officers was positioned directly below the air burst to prove that the missile could be used over populated areas. The men were reported to be unharmed.
Genie was never used in anger. Approximately 3,150 missiles were produced by the time Thiokol closed down the production line in 1963. This production run included a number of improved variants known as the MB-1-T, ATR-2A, AIR-2A and AIR-2B. Genie ultimately served with both the USAF and the Canadian Air Force. It was withdrawn from service in 1985.
Forty-six years ago this month, the United States abandoned a 7-year effort to develop a nuclear-armed, supersonic cruise missile. The joint USAF-AEC program was known as Project Pluto. The centerpiece of this program was the nuclear-fueled, ramjet-powered Supersonic Low-Altitude Missile (SLAM).
The 1950’s saw the development of myriad aircraft, missile and submarine concepts designed for delivery of nuclear weaponry over strategic distances. This developmental activity was driven by the escalating Cold War between the United States and the Soviet Union. In addition to weapons, the power of the atom was also considered for propulsion applications during this era.
SLAM was perhaps the most fearsome weapon ever conceived. The missile was designed to deliver as many as 26 nuclear bombs over the Soviet Union in a single mission. It would do this while flying at Mach 3 and less than 1,000 feet above ground level. SLAM’s shock wave overpressure alone (162 dB) would devastate structures and people along its flight path. And, as if that were not enough, the type’s nuclear-fueled ramjet would continuously spew radiation-contaminated exhaust all over the countryside.
The SLAM airframe was huge. It measured 88 feet in length, nearly 6 feet in diameter and weighed 61,000 pounds at launch. The vehicle would be fired from a ground-based launch site and accelerated to ramjet takeover speed by a trio of jettisionable rocket boosters. The nuclear-fueled ramjet was rated at 35,000 pounds of thrust.
To find its way to the target area(s), the Ling-Temco-Vought (LTV) SLAM would use a guidance system known today as TERCOM – Terrain Contour Matching. At a target, SLAM would eject an atomic warhead upwards from its payload bay. The resulting lofted trajectory gave SLAM time to depart the hot target area prior to weapon detonation. Following completion of its mission, the missile would then ditch itself by diving into a deep ocean graveyard.
The heart of the Project Pluto missile was the nuclear-fueled ramjet. An unshielded nuclear reactor, code named TORY, was devised, built and successfully tested. Testing was conducted at a special-purpose test site in Nevada. In its Tory II-C configuration, the SLAM ramjet produced over 500 megawatts of power in 5 minutes of continuous operation during a test conducted in May of 1964.
SLAM’s nap-of-the-earth, supersonic flight profile would subject the airframe to terrific airloads, vibrations and temperatures. The Project Pluto team successfully devised structural and thermal material solutions to handle the daunting flight environment. In addition, nuclear-hardened electronics and flight controls were successfully developed.
From a technological standpoint, Project Pluto proved to be entirely viable. However, doubts about its implementation started to arise as flight testing of the nuclear-powered missile was seriously considered. Where do you flight-test a radiation-spewing missile? What happens if you can’t turn-off the reactor? What do you do if the guidance system fails? Where do you dispose of the missile after a flight test? These and other disturbing questions began to trouble program officials.
Coupled with the above practical concerns of SLAM flight testing were growing political and mission obsolesence issues. Pentagon officials ultimately deemed Project Pluto as being highly provocative to the Soviet Union in the sense that the communist super power might feel compelled to develop their own SLAM. Further, American missilery was quickly developing to the point where ICBM-delivered warheads would do the job and at a lower per-unit cost.
So it was that on Wedneday, 01 July 1964, Project Pluto was canceled after 7 years of fruitful development. While no airframe was ever built and tested, SLAM technology was applied to a host of subsequent aerospace vehicle developments.
SLAM would truly have been “The Missile From Hell” had it matured to the point of flight. Indeed, the ethical issues concerning the missile’s use were quite sobering. And, owing to Murphy’s Law and its many corollaries, the chances for unintended catastrophe were high as well. Despite the allure of this “technically sweet” solution to a national defense problem, the decision to cancel Project Pluto was ultimately the only correct course to follow.
Sixty-years ago this month, the United States launched a primitive two-stage rocket from an obscure site situated on Florida’s eastern coast. The rocket was the Army’s Bumper-WAC No. 8. The then little-known launch location has since become synonymous with American aerospace achievement. We know it today as Cape Canaveral.
The Bumper Program was a United States Army effort to reach flight altitudes and velocities never before achieved by a rocket vehicle. The name “Bumper” was derived from the fact that the lower stage would act to “bump” the upper stage to higher altitude and velocity than it (i.e., the upper stage) was able to achieve on its own.
The Bumper two-stage configuration consisted of a V-2 booster and a WAC Corporal upper stage. The V-2′s had been captured from Germany following World War II while the WAC Corporal was a single stage American sounding rocket. The launch stack measured 62 feet in length and weighed around 28,000 pounds.
From a propulsion standpoint, the V-2 booster generated 60,000 pounds of thrust with a burn time of 70 seconds. The WAC Corporal rocket motor produced 1,500 pounds of thrust and had a burn time of 47 seconds.
The first Bumper-WAC shots took place at White Sands Proving Ground (WSPG) in New Mexico. The first six (6) flights were dedicated to achieving maximum altitude. Indeed, Bumper-WAC No. 5 flew to an altitude of 250 miles on Thursday, 24 February 1949.
WSPG could not be used for the last two (2) flights which required the Bumper-WAC vehicle to remain within the atmosphere. A larger range was required to handle these missions which involved a significant amount of essentially horizontal flight. Looking beyond Bumper, it was clear that future programs would also require a much larger test range as well.
After considering a number of geographical locations within the US, the new Long Range Proving Ground (LRPG) was ultimately established in the state of Florida. The LRPG locale was hot, bug-infested and covered with sand dunes and scrub palmetto. However, the LRPG was also immediately adjacent to the Atlantic Ocean which provided a vast region over which test rockets could be safely flown.
Bumper-WAC No. 7 was supposed to be the first rocket fired from the LRPG. However, Bumper-WAC No. 8 got that honor when No. 7 experienced a glitch on the pad. No. 8 was fired at 13:29 UTC on Monday, 24 July 1950. The mission failed when the rocket motor of the WAC upper stage did not ignite.
On Saturday, 29 July 1950, Bumper-WAC No. 7 was launched from the LRPG. The mission was entirely successful. The WAC upper stage burned-out at Mach 9 and flew 150 miles downrange. The maximum sustained velocity within the atmosphere was more than 3,200 mph – a record for the time.
While the Bumper Program would fade into history, the LRPG did not. History records that the fledging test facility would develop into America’s preeminent launch complex. The military services would grow both our Nation’s missile defense and space launch vehicle capabilites there. Later, NASA would come on the scene and send astronauts first into Earth orbit and then to the Moon.
Cape Canaveral now operates in a season of decline relative to our national space effort. The fabled Space Shuttle will soon be retired. The CEV Program is slated for cancelation, leaving our country without either a national manned launch vehicle or spacecraft. Very soon, we will not even be able to go to and from our own space station. The prevailing “wisdom” is that private industry will solely provide access to space in the future. And such is to be accomplished without any national system being available as a back-up.
That we as a nation find ourselves in the predicament outlined above, is at once ironic and obscene. However, this is America and we are Americans. And, despite determined and increasing assaults from without and from within, we are still a land of liberty and opportunity. We can chose a better path.
Whether Cape Canaveral has seen its best days or if those that lie ahead will be better still, it is up to the citizens of the United States to determine. The responsibility and obligation to do so can neither be evaded nor avoided. If we chose rightly, Cape Canaveral’s, and indeed our beloved country’s, best days await in the future.
To both we say with deepest sentiment: “Long may you run.”
Forty-three years ago this month, USAF Major William F. “Pete” Knight made an emergency landing in X-15 No. 1 at Mud Lake, Nevada. Knight somehow managed to save the hypersonic aircraft following a complete loss of electrical power as it passed through 107,000 feet during climb.
The famed X-15 Program conducted 199 flights between June 1959 and October 1968. North American Aviation (NAA) built three (3) X-15 aircraft. Twelve (12) men from NAA, USAF and NASA flew the X-15. Eight (8) pilots received astronaut wings for flying the X-15 beyond 250,000 feet. One (1) aircraft and one (1) pilot were lost during flight test.
The X-15 flew as fast as 4,520 mph (Mach 6.7) and as high as 354,200 feet. The basic airframe measured 50 feet in length, featured a wing span of 22 feet and had a gross weight of 33,000 pounds. The type’s Reaction Motors XLR-99 rocket engine burned anhydrous ammonia and liquid oxygen to produce a sea level thrust of 57,000 pounds. The X-15 used both 3-axis aerodynamic and ballistic flight controls.
An X-15 mission was fast-paced. Flight time from B-52 drop to unpowered landing was typically 10 to 12 minutes in duration. The pilot wore a full pressure suit and experienced 6 to 7 G’s during pull-out from max altitude. There really was no such thing as a routine X-15 mission. However, all X-15 missions had one factor in common; danger.
On Thursday, 29 June 1967, X-15 No. 1 (S/N 56-6670) made its 73rd and the X-15 Program’s 184th free flight. Launch took place at 1828 UTC as the NASA B-52B launch aircraft (S/N 52-0008) flew at Mach 0.82 and 40,000 feet near Smith Ranch, Nevada. Knight, making his 10th X-15 flight, quickly ignited the XLR-99 and started his climb upstairs.
The X-15 was performing well and Knight was enjoying the flight until 67.6 seconds into a planned 87 second XLR-99 burn. That’s when the engine suddenly quit. A couple of heartbeats later, the Stability Augmentation System (SAS) failed, the Auxiliary Power Units (APU’s) ceased operating, the X-15’s generators stopped functioning and the cockpit lights went out. This was the total hit; a complete power failure.
Pete Knight was now just along for the ride. No thrust to power the aircraft. No electrical power to run onboard systems. No hydraulics to move flight controls. Even the reaction controls appeared inoperative. The X-15 continued upward, but it wallowed aimlessly in the low dynamic pressure of high altitude flight. At this point, Knight considered taking his chances and punching-out.
The X-15 went over the top at 173,000 feet. On the way downhill, Knight was able to get some electrical power from the emergency battery. This meant that he now had some hydraulic power and could utilize the X-15’s flight control surfaces. Knight next tried to fire-up the APU’s. The right APU would not respond. The left APU fired, but the its generator would not engage.
As the X-15 descended and the dynamic pressure built-up, Knight was able to maneuver his stricken X-15. He headed for Mud Lake in a sustained 6-G turn. As he leveled off at 45,000 feet, Knight instinctively knew he could now make the east shore of the Nevada dry lake. But it was tough work to fly the X-15. Knight ended-up using both hands to fly the airplane; one on the side stick and one on the center stick.
While Knight was trying to get his airplane down on the ground in one piece, only he and his Maker knew his whereabouts. The X-15 flight test team certainly didn’t, since Knight’s radio, telemetry and radar transponder were now inop. Further, the X-15 was not being skinned tracked at the time of the electrical anomaly. Just before he touched-down at Mud Lake, Knight’s X-15 was spotted by NASA’s Bill Dana who was flying a F-104N chase aircraft.
Pete Knight made a good landing at Mud Lake. The X-15 slid to a stop. After a struggle with the release mechanism, he managed to get the canopy open. Hot and soaked with perspiration, Knight somehow removed his own helmet. A ground crewman usually did that for him. But there were no flight support people at his X-15 landing site on this day.
As he attempted to get out of the X-15 cockpit, Knight pulled an emergency release. To his surprise, the headrest blew off, bounced off the canopy and smacked him square in the head. Undeterred, Knight got out of the cockpit and onto terra firma. In the meantime, a Lockheed C-130 Hercules had landed at Mud Lake. Wearily, Pete Knight got onboard and returned to Edwards Air Force Base.
Post-flight investigation revealed that the most probable source of the X-15’s electrical failure was arcing in a flight experiment system. This system had been connected to the X-15’s primary electrical bus. The solution was to connect flight experiments to the secondary electrical bus.
Reflecting on Knight’s amazing recovery from almost certain disaster, long-time NASA flight test manager Paul Bickle claimed the fete was among the most impressive of the X-15 Program. Indeed, it was Pete Knight’s clearly uncommon piloting skill and calmness under pressure that gave him the edge.
Fifty-nine years ago this month, the No. 1 USAF/Bell X-5 variable-sweep-wing aircraft testbed took to the air for the first time with Bell test pilot Jean “Skip” Ziegler at the controls. The X-5 holds the distinction of being the first aircraft capable of changing its wing sweep while in flight.
The ability to change wing sweep during flight allows an aircraft to be flown more optimally throughout its flight envelope. For instance, low wing sweep enhances low-speed lift characteristics while high wing sweep reduces wave drag at high speeds. Unfortunately, these aerodynamic gains come at the price of increased structural weight and mechanical complexity.
During World War II, the Third Reich developed the Messerschmitt P.1101 aircraft which was configured with a ground-adjustable variable-sweep wing. The P.1101 was captured in 1945 by the United States as part of the spoils of war. The aircraft was subsequently transported to Wright Field in Ohio for detailed examination by American aeronautical experts.
The Bell Aircraft Corporation ultimately came into possession of the P.1101 in August of 1948 after it had been examined by the Air Force and subsequently declared as surplus by the service. After an abortive attempt to re-engine the aircraft, Bell abandoned its effort to fly the P.1101. The company then made a decision to develop a completely new variable-sweep-wing aircraft.
Bell secured a contract from the Air Force in February of 1949 to build a pair of experimental variable-sweep-wing aircraft. The new airplane joined the young X-plane family as the X-5. The tail numbers assigned by the Air Force were 50-1838 and 50-1839.
The X-5 wing sweep could be varied between 20 and 60 degrees in flight. This resulted in a wing span that varied between 33.5 feet at 20 degrees of sweep and 20.75 feet at 60 degrees of sweep. The X-5 measured 33.5 feet in length and had a gross take-off weight of 9,875 pounds. The aircraft was powered by a single Allison J35-A-17A turbojet rated at 4,900 pounds of sea level thrust.
The X-5 was a nimble aircraft. It flew as fast as Mach 0.95 and as high as 45,000 feet. In fact, the X-5 was used at various times as a chase aircraft in support of other flight test programs at Edwards. On the other hand, the X-5 was less than docile in terms of handling qualities. It was particularly unruly in a spin.
On Wednesday, 20 June 1951, the No. 1 X-5 (50-1838) took-off from Edwards Air Force Base on its first contractor flight. This aircraft would eventually accumulate 153 flights, the last of which occurred on Tuesday, 25 October 1955. A dozen men from Bell, USAF and NACA flew the X-5 during that period. The last man to fly the X-5 was none other than Neil Armstrong.
While the No. 1 X-5 (50-1838) survived the flight test program, the No. 2 aircraft (50-1839) did not. The aircraft first flew on 10 December 1951 and was lost following an unrecoverable spin on Wednesday, 14 October 1953. USAF Major Raymond Popson lost his life when he was unable to eject from the stricken aircraft. The flight was Popson’s first and last in the X-5. It is not clear how many flights 50-1839 made during its service life.
The Bell X-5 provided a wealth of performance, stability and control and handling qualities data relative to variable-sweep-wing flight. The aircraft served as the progenitor to a number of famous operational aircraft including the General Dynamics F-111 Aardvark, Grumman F-14 Tomcat, and Rockwell B-1B Lancer.
The surviving X-5 (50-1838) is currently on display at the United States Air Force Museum at Wright-Patterson Air Force Base in Dayton,Ohio.
Fifty-seven years ago this month, NACA test pilot A. Scott Crossfield piloted the United States Navy/Douglas D-558-I transonic research aircraft on the last of the type’s 230 flights. The flight was conducted on Wednesday, 10 June 1953 at Edwards Air Force Base, California.
Flight near and beyond the speed of sound is characterized by large variations in flowfield density. Variable density flow is known as compressible flow. A key compressible flow phenomenon is the formation of shock waves. These fluid dynamic flow features are the result of locally supersonic flow being deflected or turned.
As every aircraft has a distinct shape, it also has its own distinct shock wave system. The topology and strength of this 3-dimensional shock wave system significantly affects aircraft flight performance, stability and control, handling qualities, airframe buffet characteristics and airloads.
Following World War II, the United States initiated a sustained flight research effort in the realm of transonic and supersonic flight. In league with the US military and the National Advisory Committee For Aeronautics (NACA), the American aeronautical industry designed and built a variety of aircraft used to conduct flight research during the 1940’s and 1950’s. These experimental aircraft were the first of the fabled X-planes.
In June of 1945, the Douglas Aircraft Company was awarded a contract by the United States Navy (USN) to build a total of six (6) flight research aircraft. These vehicles would be used in a two phase flight research program. Phase I was devoted to transonic flight testing while Phase II would investigate supersonic flight. The Phase I aircraft was known as the D-558-I Skystreak while the Phase II airplane was called the D-558-II Skyrocket.
The USN/Douglas D-558-I Skystreak measured 36-feet in length and had a wingspan of 25-feet. The straight-winged aircraft weighed a bit over 10,000 pounds and was powered by an Allison J35 turbojet rated at 5,000 pounds of sea level thrust. The aircraft was single place and employed ground take-off. Three (3) copies were made; BuAer tail numbers 37970, 37971 and 37972.
Later painted white to improve visibility, each Skystreak was originally painted a stunning red. This led to the type’s nickname of the “Crimson Test Tube”. Other nicknames included the “Flying Stove Pipe” and the “Supersonic Test Tube”. This last moniker is misleading in that the aircraft could only go slightly supersonic and only in a dive.
Along with its D-558-II companion, the D-558-I helped write the book on transonic aircraft aerodynamics. The D-558-I Skystreak acquired vital flight data relative to aircraft stability and control, handling qualities, airframe buffet and airloads. Those data are used to support aircraft design efforts down to the present day.
Pilots reported that the D-558-I exhibited generally favorable handling qualities. However, the Skystreak had its share of peculiar transonic aerodynamic attributes as well. Wing drop due to asymmetric shock-induced separation was one such phenomenon. Reduced control effectiveness and severe lateral-directional oscillations, both due to shock wave-induced flow separation at high Mach number, were exhibited as well.
Beyond 0.94 Mach number, the D-558-I experienced a phenomenon known as “Mach Tuck”. This condition is attributable to an aftward shift in the aircraft transonic center-of-pressure location as the pressure pattern over the aircraft changes with Mach number. This is equivalent to an increase in nose down pitching moment. Taken to extremes, the “Mach Tuck” flight condition is unrecoverable due to an exceedance of pitch control authority.
Approximately 15 men flew the D-558-I Skystreak 230 times between April of 1947 and June of 1953. One aircraft and one pilot was lost during the type’s flight research program. NACA test pilot Howard Lilly died and aircraft 37971 was destroyed when a J35 turbojet compressor blade failed during take-off on Tuesday, 25 November 1947.
Today the surviving aircraft are publically displayed in tribute to the Skystreak’s contributions to aeronautics. Tail No 37970 is displayed at the Naval Air Museum in Pensacola, Florida while Tail No. 37972 can be viewewd at the Carolinas Avaiation Museum in Charlotte, North Carolina.
Forty-four years ago this month, NASA astronauts Thomas P. Stafford and Eugene A. Cernan became the 7th two-man Gemini crew to orbit the Earth. Known as Gemini 9A, the mission was the 13th manned spaceflight flown by the United States.
The Gemini Program was absolutely critical to the success of America’s lunar landing effort. A total of 10 Gemini missions was flown during a 20-month period between 1965 and 1966. Gemini demonstrated the key capabilities of rendezvous and docking, orbital maneuvering, long duration spaceflight and extra vehicular activity.
Each Gemini mission had its share of difficulties which arose and had to be overcome during flight. Gemini 9A was arguably the most ill-fortuned and technically frustrating of the series. Mission goals included rendezvous and docking with an Agena Target Vehicle (ATV), maneuvering the combined Gemini-Agena combination and demonstration of the first manned rocket pack; the United States Air Force Astronaut Maneuvering Unit (AMU).
The original Gemini 9 prime crew was Elliot M. See and Charles A. Bassett. However, both men died on Monday, 28 February 1966 as they attempted to land their T-38 aircraft during a rain storm in St. Louis, Missouri. The Gemini 9 back-up crew of Stafford and Cernan somehow managed to land their T-38 aircraft during that same storm. The men were appointed as the prime crew with the devastating loss of See and Bassett.
On Tuesday, 17 May 1966, an ATV was launched ahead of Gemini 9. The Agena vehicle never made it to orbit due to a problem with its Atlas booster. McDonnell engineers hurriedly conceived and built a substitute for the ATV known as the Augmented Target Docking Adapter (ATDA). While Stafford and Cernan could rendezvous and dock with the ATDA, they could not change their orbital path since the ATDA had no propulsion system.
With the loss of the ATV and the introduction of the ATDA, Gemini 9 now came to be known as the Gemini 9A mission. The ATDA was successfully fired into orbit on Wednesday, 01 June 1966. However, the ATDA’s nose shroud had failed to jettison. Thus, Gemini 9A would not be able to dock with the ATDA.
The launch window for Gemini 9A was only 40 seconds on the day that the ATDA was launched. That window came and went when computer problems arose at a most inopportune moment. Having been denied the opportunity to launch, Stafford and Cernan unstrapped and waited to fly another day.
On Friday, 03 June 1966, Gemini 9A lifted-off from LC-19 at Cape Canaveral, Florida. Lift-off time was 1339 UTC. Within 5 hours, the crew caught up with the ATDA. What they saw did not inspire hope. The ATDA’s shroud indeed had not jettisoned properly. Commander Stafford radioed to Mission Control: “It looks like an angry alligator out here rotating around.”
The Gemini 9A crew asked for permission to use the nose of their spacecraft to nudge the recalcitrant shroud from the ATDA. Permission denied. The Gemini spaceraft might be damaged. How about performing an EVA and having Cernan cut the shroud attachment lanyards? No way. Sharp-edged debris might pierce Cernan’s EVA suit.
Making the best of the situation, Stafford and Cernan moved away from the ATDA and then rendezvoused with it again. They did this a number of times to gain practice. They also performed stationkeeping with the ATDA to learn the nuances of that flight mode.
Cernan’s much anticipated EVA with the AMU took place on Sunday, 05 June 1966. That particular experience deserves an article all its own. Suffice it to say that things did not go well. Working outside the spacecraft was much more physically demanding and functionally non-intuitive than expected.
Cernan found that any movement of his limbs resulted in unwanted reactions on his body. It was exceedingly difficult to remain still and perform useful work. He had to continually fight to maintain body position. Further, the Gemini spacecraft did not have enough hand-holds. Cernan’s exertions were such that his heart rate peaked at 195 beats per minute. Perspiration fogged his visor. Now he was blind.
Cernan struggled to get to the AMU which was stored in the Gemini’s aft adapter. He prepared the unit for free-flight, but continued to labor. He ultimately came to the conclusion that free-flying the AMU was infeasible on this mission. Dishearted and still blinded by the perspiration-induced fog on his visor, Cernan managed to safely return to the spacecraft cabin and secured the hatch. Total EVA time was 128 minutes.
Stafford and Cernan completed their demanding mission with reentry and splashdown in the Atlantic Ocean on Monday, 06 June 1966. They excuted a computer-controlled entry and landed less than one-half mile from the prime recovery ship; the USS Wasp. Official mission elapsed time was 72 hours, 20 minutes and 50 seconds.
It is worth noting that Gemini 9A, like all Gemini missions, was a test flight. The ATDA and AMU experiences were certainly frustrating, but not without merit from a learning standpoint. That learning was put to good use as evidenced by the accomplishments of Gemini’s 10, 11 and 12.
Rendezvous, docking and orbital maneuvering with the ATV all went extremely well on the last trio of Gemini missions. And on Gemini 12, the most vexing of early manned spaceflight problems was solved; that of EVA. Indeed, with the aid of techniques and equipment developed from Gemini 9A lessons-learned, one Edward E. “Buzz” Aldrin convincingly demonstrated the feasibility of an astronaut performing meaningful work in space.
Seventy-five years ago today, pioneering rocket scientist Robert H. Goddard and staff fired a liquid-fueled rocket to a record altitude of 7,500 feet above ground level. The record-setting flight took place at Roswell, New Mexico.
Robert Hutchings Goddard was born in Worcester, Massachusetts on Thursday, 05 October 1882. He was enamored with flight, pyrotechnics, rockets and science fiction from an early age. By the time he was 17, Goddard knew that his life’s work would combine all of these interests.
Goddard was a sickly youth, but spent his well moments as a voracious reader of all manner of science-oriented literature. He graduated in 1904 from South High School in Worcester as the valedictorian of his class. He matriculated at Worcester Polytechnic and graduated with a Bachelor of Science degree in physics in 1908. A Master of Science degree and Ph.D. from Worcester’s Clark University followed in 1910 and 1911, respectively.
Goddard spent the next eight years of his life working on numerous propulsion and rocket-related projects. Then, in 1919, he published his now-famous scientific treatise entitled A Method of Reaching Extreme Altitudes. In that paper, the press glommed on to Goddard’s passing mention that a multi-staged rocket could conceivably fly all the way to the Moon.
Goddard was roundly ridiculed for his fanciful prognostications about Moon flight. The New York Times was especially derogatory in its estimation of Goddard’s ideas and accused him of junk science. A Times editorial even criticized Goddard for his “misconception” that a rocket could produce thrust in the vacuum of space.
Even the U.S. government largely ignored Goddard. This scornful treatment to which Goddard was subject hurt him profoundly. So much so that he spent the remainder of his life alienated from the denizens of the press as well as the dolts of governmental employ.
Despite the blow to his professional reputation, Goddard resolutely pressed on with his rocket research. Indeed, after more that five years of intense development effort, Goddard and his staff launched the first liquid-fueled rocket on Tuesday, 16 March 1926 in Auburn, Massachusetts. The flight duration was short (2.5 seconds) and the peak altitude tiny (41 feet), but Goddard proved that liquid rocket propulsion was feasible.
Goddard’s liquid-fueled rocket testing would ultimately lead him from the countryside of New England to the desert of the Great South West. With financial support from Harry Guggenheim and the public backing of Charles Lindbergh, Goddard transfered his testing activities to Roswell, New Mexico in 1930. He would continue liquid-fueled rocket testing there until May 1941.
On Friday, 31 May 1935, experimental rocket flight A-8 took to the air from Goddard’s Roswell, New Mexico test site at 1430 UTC. Roughly 15 feet in length and weighing approximately 90 pounds at lift-off, the 9-inch diameter A-8 achieved a maximum altitude of 7,500 feet (1.23 nautical miles) above the desert floor. Only a flight in March of 1937 would go higher (9,000 feet).
Robert Goddard was ultimately credited with 214 U.S. patents for his rocket development work. Only 83 were awarded in his life time. His far-reaching inventions included rocket nozzle design, regenerativley cooled rocket engines, turbopumps, thrust vector controls, gyroscopic control systems and more.
Goddard died at the age of 62 from throat cancer in Baltimore, Maryland on Friday, 10 August 1945. Many years would pass before the full import of his accomplishments was comprehended. Then, the posthumously-bestowed recognition came in torrents. In 1959, Congress issued a special gold medal in Goddard’s honor. The Goddard Spaceflight Center was so named by NASA in 1959 as well. Many more such bestowals followed.
Perhaps the most meaningful of the recognitions ever accorded Robert Hutchings Goddard occurred 24 years after his passing. It was in connection with the first manned lunar landing in July of 1969. And it was poetic not only in terms of its substance and timing, but more particularly in light of the source from whence the recognition came.
A terse statement in the New York Times corrected a long-standing injustice. It read: “Further investigation and experimentation have confirmed the findings of Issac Newton in the 17th century, and it is now definitely established that a rocket can function in a vaccum as well as in an atmosphere. The Times regrets the error.”
Thirty-seven years ago this week, astronauts Pete Conrad, Joe Kerwin and Paul Weitz became the first NASA crew to fly aboard the recently-orbited Skylab space station. Not only would the crew establish a new record for time in orbit, they would effect critical repairs to the space station which had been seriously damaged during launch.
Skylab was America’s first space station. The program followed closely on the heels of the historic Apollo lunar landing effort. Skylab provided the United States with a unique space platform for obtaining vast quantities of scientific data about the Earth and the Sun. It also served as a means for ascertaining the effects of long-duration spaceflight on human beings.
A Saturn IVB third stage served as Skylab’s core. This huge cylinder, which measured 48-feet in length and 22-feet diameter, was modified for human occupancy and was known as the Orbital Workshop (OWS). With the addition of a Multiple Docking Adapter (MDA) and Airlock Module (AM), Skylab had a total length of 83-feet.
Skylab was also outfitted with a powerful space observatory known as the Apollo Telescope Mount (ATM). This unit sat astride the MDA and was configured with a quartet of electricity-producing solar panels. The OWS had a pair of solar panels as well. The entire Skylab stack weighed 85 tons.
The Skylab space station (Skylab 1) was placed into a 270-mile orbit using a Saturn V launch vehicle on Monday, 14 May 1973. Upon reaching orbit, it quickly became apparent that all was far from well aboard the space station. The micro-meteoroid shield and solar panel on one side of the OWS had been lost during ascent. The other OWS solar panel was stuck and did not deploy as planned.
With the loss of an OWS solar panel, Skylab would not have enough electrical energy to conduct its mission. The station was also heating up rapidly (temperatures approached 190 F at one point). The lost micro-meteoroid shield also provided protection from solar heating. Sans this protection, internal temperatures could rise high enough to destroy food, medical supplies, film and other perishables and render the OWS uninhabitable.
NASA engineers quickly went to work developing fixes for Skylab’s problems. A mechanism was invented to free the stuck solar panel. A parasol of gold-plated flexible material, deployed from an OWS scientific airlock, was then fashioned and tested on the ground. This material would cover the exposed portion of the OWS and provide the needed thermal shielding.
The onus was now on the Skylab 2 crew of Conrad, Kerwin and Weitz to implement the requisite fixes in orbit. On Friday, 25 May 1973, the Skylab 2 crew and their Apollo Command and Service Module (CSM) were rocketed into orbit by a Saturn IB launch vehicle. They quickly rendezvoused with Skylab and verified its sad condition. It was time to get to work.
The first order of business was to try to free the stuck solar panel. As Conrad flew the CSM in close proximity to Skylab, Kerwin held Weitz by the feet as the latter leaned out of the open CSM hatch and attempted to release the stuck solar panel with a pair of special cutters. No joy in spaceville. The solar panel refused to deploy.
The Skylab 2 crew next attempted to dock with Skylab. They tried six times and failed. The CSM drogue and probe was not functioning properly. The crew had to fix it or go home. With great difficulty, they did so and were finally able to dock with Skylab. The objective now was to enter Skylab and deploy the parasol thermal shield.
With Conrad remaining in the CSM, Kerwin and Weitz sported gas masks and cautiously entered Skylab. The temperature inside of the OWS was 130 F. Fortunately, the air was found to be of good quality and the pair went to work deploying the thermal shield through a scientific airlock. The deployment was successful and the temperature started to slowly fall.
It would not be until Thursday, 07 June 1973 that the stuck solar panel finally would be freed. On that occasion, Conrad and Kerwin donned EVA suits and spent 8 hours working outside of Skylab. Their initial efforts with the cutters were unsuccesful.
Undeterred, Conrad and Kerwin improvised and were able to cut the strap that restrained the solar panel. Then, heaving with all their might, the pair finally freed the solar panel. In obedience to Newton’s 3rd Law, as the solar panel deployed in one direction, the astronauts went flying in the other. Happily, they were able to collect themselves and safely reenter the now adequately-powered Skylab.
Skylab 2 went on to spend 28 days in orbits; a record for the time. This record was quickly eclipsed by the Skylab 3 and Skylab 4 crews which spent 59 and 84 days in space, respectively. Skylab was an unqualified success and provided a plethora of terrestrial, solar and human factors data of immense importance to space science. These data played a vital role in the design and development of the ISS.
Skylab was abandoned following the Skylab 4 mission in February of 1974. The plan was to reactivate it and raise its orbit using the Space Shuttle when the latter became operational. Unfortunately, a combination of a rapidly deteriorating orbit and delays in flying the Shuttle conspired against bringing this plan to fruition. Skylab reentered the Earth’s atmosphere and broke-up near Australia in July of 1979.
Forty-one years ago this week, Apollo 10 set sail for the Moon on a mission that would see American astronauts fly within a mere 8 nautical miles of the lunar surface. This historic flight cleared the way for the first manned lunar landing just 2 months later.
The infamous Apollo 1 fire in January 1967 resulted in a 21-month suspension of manned spaceflight operations for the United States. By the time the first post-Apollo 1 flight occurred in October 1968, a scant 14 months remained for fulfillment of the national goal to land men on the Moon and return them safely to the Earth by the end of the 1960’s.
Not a few held the position that the lunar landing goal could not be achieved by the end of the decade. Some went so far as to say a successful lunar landing would never occur. Space program opponents had a field day. As always, these ever-present naysayers averred that the US should be spending its money on more “socially-important” programs.
Despite the undercurrents of pessimism and vacillation, NASA resolutely pressed forward. In October of 1968, the Apollo Command Module was thoroughly tested in Earth orbit during Apollo 7. Then, in December of 1968, the mighty Saturn V launch vehicle placed the crew of Apollo 8 in lunar orbit. Finally, the Lunar Module was successfully flight-tested by the Apollo 9 astronauts in March of 1969.
Incredibly, each of the key Apollo flight hardware had been individually tested during 3 missions that were flown over the course of 5 months. Now it was time to test them together. Enter Apollo 10. The purpose of Apollo 10 was to fly to the Moon and do everything short of an actual landing. Apollo 10 was thus a complete dress rehearsal for Apollo 11 sans the landing.
On Sunday, 18 May 1969, Apollo 10 lifted-off from Cape Canaveral’s LC 39B at 16:49 UTC. The crew consisted of Mission Commander Thomas P. Stafford, Command Module Pilot John W. Young and Lunar Module Pilot Eugene A. Cernan. Riding on 7.5 million pounds of first stage thrust, the Saturn V accelerated, went through 2 staging events and arrived in Earth orbit 12 minutes after lift-off.
Following systems checkout, the Saturn IVB third was re-ignited to start the translunar injection (TLI). Apollo 10 entered lunar orbit almost 76 hours after launch. The astronauts later circularized their orbit at 60 nautical miles and then rested in preparation for the next day’s lunar landing rehearsal.
At a mission elapsed time of 98 hours, the Apollo 10 Command and Lunar Modules undocked and separated from one another. Stafford and Cernan crewed the Lunar Module and while John Young flew alone in the Command Module. Over the next 18 hours the Lunar Module crew flew all the flight maneuvers and executed all the procedures associated with a lunar landing.
As planned, Stafford and Cernan did not land on the Moon. The closest approach to the lunar surface was approximately 8 nautical miles. The view was great and thoughts about landing were in the crew’s minds. In actuality, the Apollo 10 Lunar Module was not configured for a lunar landing. Had the crew attempted such, they would have been doomed.
The Lunar Module’s return to rendezvous and dock with the Command Module was unremarkable with the exception of staging. The crew mistakenly left the Abort Guidance System (AGS) in AUTOMATIC rather than ATTITUDE HOLD. At separation of the Ascent and Descent Stages, the Ascent Stage wildly gyrated and flirted with gimbal lock.
The crew quickly discovered the AGS switch position problem and brought the vehicle back into control. But it was pretty hairy there for a few moments. As Stafford and Cernan worked to steady their steed, both astronauts articulated their surprise and concern with the dire situation using colorful and interesting language not typically associated with refined behavior.
Happily, the trip back to Earth was nominal. Apollo 10 landed at 16:52 UTC in the Pacific Ocean on Monday, 26 May 1969. Their mission had been highly successful. The way was now clear for an actual lunar landing attempt. That opportunity came just 2 months later. History records that men landed on the Moon and safely returned to the Earth in July 1969.
John Young returned to and landed on the Moon as Commander of Apollo 16 in April of 1972. He went on to command the first Space Shuttle mission (STS-1) in April of 1981. Gene Cernan was Commander of Apollo 17 in December 1972 and was the last man to walk on the Moon. Tom Stafford never returned to the Moon. However, he served as Apollo Spacecraft Commander for the ASTP mission in July of 1975.
Forty-three years ago today, NASA’s experimental M2-F2 lifting body flight research aircraft was demolished in a horrific landing mishap on Rogers Dry Lake at Edwards Air Force Base. Although critically injured, NASA test pilot Bruce A. Peterson survived the mishap.
A lifting body is a wingless aircraft wherein the aerodynamic lift required for flight is derived solely from the fuselage. Interest in such a configuration stems from the type’s inherent suitability for lifting atmospheric entry from space. The primary attributes being favorable cross-range capability and aerodynamic heating performance.
Lifting body concepts date back to at least the 1950’s. From 1963 to 1975, both NASA and the United States Air Force conducted a number of manned lifting body flight research programs. The aircraft involved were the M2-F1, M2-F2, M2-F3, HL-10, X-24A and X-24B. All were flown out of Edwards Air Force Base between 1963 and 1975.
The favorable hypersonic flight performance of lifting bodies comes at a price. Specifically, lifting bodies are not particularly good subsonic aircraft from the standpoint of lateral-directional handling qualities. The type also falls like a rock in the approach and landing phase. Due to characteristically-low values of subsonic lift-to-drag ratio, touchdown speeds can exceed 250 knots.
The M2-F2 was the first of the heavy weight lifting bodies. It measured 22 feet in length and 9.4 feet in span. The aircraft had an empty weight of 4,630 pounds. The M2-F2 had boosted hydraulic 3-axis flight controls and a stability augmentation system. The vehicle was also configured with a quartet of hydrogen peroxide rockets rated at 400 pounds of thrust each.
On Wednesday, 10 May 1967, the M2-F2 (NASA S/N 803) fell away from the fabled B-52B (S/N 52-0008) launch aircraft at an altitude of 44,000 feet. NASA test pilot Bruce A. Peterson was at the controls of the M2-F2. This was Peterson’s 3rd flight in the M2-F2 and the aircraft’s 16th overall. It would be the last research flight for both.
The early part of the mission was unremarkable. Then the flight test gremlins made their presence known. Passing through 7,000 feet in a steep glide, Peterson pushed forward on the control column and brought the M2-F2 to quasi-zero angle-of-attack. The aircraft quickly entered a Dutch Roll with extreme, rapid lateral excusions.
Peterson increased angle-of-attack to arrest the wild lateral-directional motions of the M2-F2. However, he was no longer pointed toward Runway 18 on Rogers Dry Lake as intended. The ground was coming up rapidly and he would have to land the M2-F2 on a part of the lakebed that did not have the typical visual aids required for correctly judging height above surface level.
Peterson might have gotten himself and the M2-F2 on the ground in one piece except for the helicopter that now loomed directly ahead in his landing path. Not that it was the helicopter pilot’s fault. It was just that the M2-F2 had strayed so far from its intended flight path that the helicopter was suddenly a navigational hazard.
Managing to somehow avoid a collision with the flight support helicopter, Peterson now fired his landing rockets in an attempt to stay in the air a little longer. He then hit the landing gear switch. In 1.5 seconds the gear would be down and locked. Unfortunately, there was only one second of flight time remaining before touchdown.
As the M2-F2 contacted the lakebed at 220 knots, its main landing gear was jammed back up into the fuselage. That was the end of the ball game. The M2-F2 tumbled end-over-end across Rogers Dry Lake shearing off the canopy, main gear and right vertical tail. The battered and twisted airframe finally came to rest inverted on the lakebed.
Incredibly, rescue crews found Bruce Peterson still alive as they came upon the crash scene. He was even conscious, However, the pilot was terribly hurt. Peterson’s oxygen mask had been torn off as the M2-F2 tumbled six (6) times. He received severe facial injuries due to repeated impact with the lakebed surface. In addition, Peterson suffered a fractured skull, severe damage to his right eye and a broken hand.
Bruce Peterson came back from his brush with eternity. He needed extensive reconstructive surgery on his face and lost the sight in his right eye. Peterson served as a project engineer for a number of NASA flight programs and even flew as a Marine reservist. He later served as a safety officer on the B-2 flight test effort. Bruce Peterson passed away at the age of 72 on 01 May 2006.
For those who remember, “The Six-Million-Dollar Man” was a television series about a fictional test pilot who had been badly injured in an aircraft accident. In the storyline, the fictional character was “rebuilt” by doctors using bionic technology. Trivia buffs may be interested to know that the basis for “The Six-Million-Dollar Man” was Bruce Peterson’s M2-F2 experience.
For those that remember, the “The Six-Million-Dollar Man” was a televison series about a fictional test pilot who had been badly injured in an aircraft accident. In the storyline, the fictional character was “rebuilt” by doctors using bionic technology. Trivia buffs may be interested to know that the basis for “The Six-Million-Dollar Man” was Bruce Peterson’s terrifying M2-F2 crash.
Forty-nine years ago this week, United States Navy Commander Alan Bartlett Shepard, Jr. became the first American to be launched into space. Shepard named his Mercury spacecraft “Freedom 7”.
Officially designated as Mercury-Redstone 3 (MR-3) by NASA, the mission was America’s first true attempt to put a man into space. MR-3 was a sub-orbital flight. This meant that the spacecraft would travel along an arcing parabolic flight path having a high point of about 115 nautical miles and a total range of roughly 300 nautical miles. Total flight time would be about 15 minutes.
The Mercury spacecraft was designed to accommodate a single crew member. With a length of 9.5 feet and a base diameter of 6.5 feet, the vehicle was less than commodious. The fit was so tight that it would not be inaccurate to say that the astronaut wore the vehicle. Suffice it to say that a claustrophobic would not enjoy a trip into space aboard the spacecraft.
Despite its diminutive size, the 2,500-pound Mercury spacecraft (or capsule as it came to be referred to) was a marvel of aerospace engineering. It had all the systems required of a space-faring craft. Key among these were flight attitude, electrical power, communications, environmental control, reaction control, retro-fire package, and recovery systems.
The Redstone booster was an Intermediate Range Ballistic Missile (IRBM) modified for the manned mission. The Redstone’s uprated A-7 rocket engine generated 78,000 pounds of thrust at sea level. Alcohol and liquid oxygen served as propellants. The Mercury-Redstone combination stood 83 feet in length and weighed 66,000 pounds at lift-off.
On Friday, 05 May 1961, MR-3 lifted-off from Cape Canaveral’s Launch Complex 5 at 14:34:13 UTC. Alan Shepard went to work quickly calling out various spacecraft parameters and mission events. The astronaut would experience a maximum acceleration of 6.5 g’s on the ride upstairs.
Nearing apogee, Shepard manually controlled Freedom 7 in all 3 axes. In doing so, he positioned the capsule in the required 34-degree nose-down attitude. Retro-fire occurred ontime and the retro package was jettisoned without incident. Shepard then pitched the spacecraft nose to 14 degrees above the horizon preparatory to reentry.
Reentry forces quickly built-up on the plunge back into the atmosphere with Shepard enduring a maximum deceleration of 11.6 g’s. He had trained for more than 12 g’s prior to flight. At 21,000 feet, a 6-foot droghue chute was deployed followed by the 63-foot main chute at 10,000 feet. Freedom 7 splashed-down in the Atlantic Ocean 15 minutes and 28 seconds after lift-off.
Following splashdown, Shepard egressed Freedom 7 and was retreived from the ocean’s surface by a recovery helicopter. Both he and Freedom 7 were safely onboard the carrier USS Lake Champlain within 11 minutes of landing. During his brief flight, Shepard had reached a maximum speed of 5,180 mph, flown as high as 116.5 nautical miles and traveled 302 nautical miles downrange.
The flight of Freedom 7 had much the same effect on the Nation as did Lindbergh’s solo crossing of the Atlantic in 1927. However, in light of the Cold War fight against the world-wide spread of Soviet communism, Shepard’s flight arguably was more important. Indeed, Alan Shepard became the first of what Tom Wolfe called in his classic book “The Right Stuff”, the American single combat warrior.
For his heroic MR-3 efforts, Alan Shepard was awarded the Distinguished Service Medal by an appreciative nation. In February 1971, Alan Shepard walked on the surface of the Moon as Commander of Apollo 14. He was the lone member of the original Mercury Seven astronauts to do so. Shepard was awarded the Congressional Space Medal of Freedom in 1978.
Alan Shepard succumbed to leukemia in July of 1998 at the age of 74. In tribute to this American space hero, naval aviator and US Naval Academy graduate, Alan Shepard’s Freedom 7 spacecraft now resides in a place of honor at the United States Naval Academy in Annapolis, Maryland.
Fifty-nine years ago today, the first flight test of a full-scale Lockheed X-7A ramjet test vehicle took place near Alamogordo, New Mexico. However, the dreaded flight test gremlins prevailed on this occasion as the entire X-7 launch stack disintegrated shortly after drop from its USAF B-29 launch aircraft.
The inauspicious start to the X-7 flight test program on Thursday, 26 April 1951 was but a momentary bump in the road. Ultimately, that road would lead to significant technological progress in the development of ramjet propulsion systems. Approximately 130 flight tests involving the X-7 would be conducted between 1951 and 1960.
The beginning of the X-7 program dates back to December of 1946. At that time, the United States was on the cusp of an unprecedented period of frontiersmanship in the realm of high-speed flight. Among other needs, a flying testbed was required to perform ramjet propulsion flight research.
A ramjet is a form of airbreathing propulsion well suited for flight up to a Mach number of about 5. Unlike the turbojet, a ramjet contains no internal rotating machinery. Flow compression comes entirely from deceleration of the supersonic freestream. However, a ramjet cannot produce static thrust. Hence, it must be boosted to flight speed via another propulsion system such as a turbojet or rocket.
The X-7 was rocket-boosted to ramjet take-over conditions. Booster thrust was on the order of 100,000 pounds with a burn time of 5 seconds. Following booster separation, the type would fly on ramjet power until fuel exhaustion. The ramjet test article was slung under the belly of the X-7 airframe which made for an asymmetric vehicle configuration.
The entire X-7A-1 launch stack measured almost 33 feet in length and had a gross weight of about 8,000 pounds. Later variants such as the X-7A-3 and XQ-5 would be longer by 3 and 4 feet, respectively. However, their gross weight was about the same as that of the X-7A-1 configuration.
The X-7 was designed for reusability. Vehicle recovery was effected via a multi-segment parachute system. This feature afforded engineers the unique opportunity to make a post-flight inspection of each ramjet engine test article. These inspections of flight hardware made for a more reliable means of making needed propulsion system design improvements.
Typically, the X-7’s long conical nose penetrated several feet into the soil at landing. The result was that the X-7 airframe stuck out of the ground with the main parachute usually draped over the vehicle’s aft end. This somewhat comical operational feature made the X-7 much easier to locate on the floor of the vast desert test range.
The X-7 was utilized to flight test ramjet engines that ranged from 20 to 36 inches in diameter. Key propulsion performance data were telemetered to ground stations for post-flight analysis. The ability to test an assortment of ramjet engine configurations during many flights produced a wealth of ramjet propulsion data over the life of the X-7 program.
The X-7 established a variety of flight performance records during its heyday. The type’s airbreathing propulsion speed, altitude and range records included 2,880 mph (Mach 4.3), 106,000 feet and 134 miles, respectively. Note that these marks were all accomplished in the 1950’s.
The technological legacy of the X-7 program is impressive. Indeed, flight vehicles such as the Boeing BOMARC, Lockheed SR-71 and Lockheed D-21 were direct beneficiaries of X-7 propulsion flight research. Though difficult to assess the extent thereof, Lockheed’s legendary Advanced Development Program (i.e., Skunk Works) has undoubtably benefitted from the X-7’s rich propulsion legacy as well.
Fifty-one years ago this month, NASA held a press conference in Washington, D.C. to introduce the seven men selected to be Project Mercury Astronauts. They would become known as the Mercury Seven or Original Seven.
Project Mercury was America’s first manned spaceflight program. The overall objective of Project Mercury was to place a manned spacecraft in Earth orbit and bring both man and machine safely home. Project Mercury ran from 1959 to 1963.
The men who would ultimately become Mercury Astronauts were among a group of 508 military test pilots originally considered by NASA for the new role of astronaut. The group of 508 candidates was then successively pared to 110, then 69 and finally to 32. These 32 volunteers were then subjected to exhaustive medical and psychological testing.
A total of 18 men were still under consideration for the astronaut role at the conclusion of the demanding test period. Now came the hard part for NASA. Each of the 18 finalists was truly outstanding and would be a worthy finalist. But there were only 7 spots on the team.
On Thursday, 09 April 1959, NASA publicly introduced the Mercury Seven in a special press conference held for this purpose at the Dolley Madison House in Washington, D.C. The men introduced to the Nation that day will forever hold the distinction of being the first official group of American astronauts. In the order in which they flew, the Mercury Seven were:
Alan Bartlett Shepard Jr., United States Navy. Shepard flew the first Mercury sub-orbital mission (MR-3) on Friday, 05 May 1961. He was also the only Mercury astronaut to walk on the Moon. Shepherd did so as Commander of Apollo 14 (AS-509) in February 1971. Alan Shepard died from leukemia on 21 July 1998 at the age of 74.
Vigil Ivan Grissom, United States Air Force. Grissom flew the second Mercury sub-orbital mission (MR-4) on Friday, 21 July 1961. He was also Commander of the first Gemini mission (GT-3) in March 1965. Gus Grissom might very well have been the first man to walk on the Moon. But he died in the Apollo 1 Fire, along with Astronauts Edward H. White II and Roger Chaffee, on Friday, 27 January 1967. Gus Grissom was 40 at the time of his death.
John Herschel Glenn Jr., United States Marines. Glenn was the first American to orbit the Earth (MA-6) on Thursday, 22 February 1962. He was also the only Mercury Astronaut to fly a Space Shuttle mission. He did so as a member of the STS-95 crew in October of 1998. Glenn was 77 at the time and still holds the distinction of being the oldest person to fly in space. John Glenn will be 89 in July 2010.
Malcolm Scott Carpenter, United States Navy. Carpenter became the second American to orbit the Earth (MA-7) on Thursday, 24 May 1962. This was his only mission in space. Carpenter subsequently turned his attention to under-sea exploration and was an aquanaut on the United States Navy SEALAB II project. Scott Carpenter will be 85 in May 2010.
Walter Marty Schirra Jr., United States Navy. Schirra became the third American to orbit the Earth (MA-8) on Wednesday, 03 October 1962. He later served as Commander of Gemini 6A (GT-6) in December 1965 and Apollo 7 (AS-205) in October 1968. Schirra was the only Mercury Astronaut to fly Mercury, Gemini and Apollo space missions. Wally Schirra died from a heart attack in May 2007 at the age of 84.
Leroy Gordon Cooper Jr., United States Air Force. Cooper became the fourth American to orbit the Earth (MA-9) on Wednesday, 15 May 1963. In doing so, he flew the last and longest Mercury mission (22 orbits, 34 hours). Cooper was also Commander of Gemini 5 (GT-5), the first long-duration Gemini mission, in August 1965. Gordo Cooper died from heart failure in October 2004 at the age of 77.
Donald Kent Slayton, United States Air Force. Slayton was the only Mercury Astronaut to not fly a Mercury mission when he was grounded for heart arrythemia in 1962. He subsequently served many years on Gemini and Apollo as head of astronaut selection. He finally got his chance for spaceflight in July 1975 as a crew member of the Apollo-Soyuz mission (ASTP). Deke Slayton died from brain cancer in June of 1993 at the age of 69.
History records that the Mercury Seven was the only group of NASA astronauts that had a member that flew each of America’s manned spacecraft (i.e, Mercury, Gemini, Apollo and Shuttle). Though just men and imperfect mortals, we salute each of them for their genuinely heroic deeds and unique contributions made to the advancement of American manned spaceflight.
Twenty-nine years ago today, the United States successfully launched the Space Shuttle Columbia into orbit about the Earth. It was the maiden flight of the Nation’s Space Transportation System (STS).
The Space Shuttle was unlike any manned space vehicle ever flown. A giant aircraft known as the Orbiter was side-mounted on a huge liquid-propellant stage called the External Tank (ET). Flanking opposing sides of the ET was a pair of Solid Rocket Boosters (SRB). The Orbiter, SRB’s and ET measured 122 feet, 149 feet and 154 feet in length, respectively.
The Space Shuttle system was conceived with an emphasis on reusability. Each Orbiter (Columbia, Challenger, Atlantis, Discovery and Endeavor) was designed to fly 100 missions. Each SRB was intended for multiple mission use as well. The only single-use element was the ET since it was more cost effective to use a new one for each flight than to recover and refurbish a reusable version.
NASA called STS-1 the boldest test flight in history. Indeed, the STS-1 mission marked the first time that astronauts would fly a space vehicle on its inaugural flight! STS-1 was also the first time that a manned booster system incorporated solid rocket propulsion. Unlike liquid propellant rocket systems, once ignited, the Shuttle’s solid rockets burned until fuel exhaustion.
And then there was the Orbiter element which had its own new and flight-unproven propulsion systems. Namely, the Space Shuttle Main Engines (SSME) and Orbital Maneuvering System (OMS). Each of the three (3) SSME’s generated 375,000 pounds of thrust at sea level. Thrust would increase to 475,000 pounds in vacuum. Each OMS rocket engine produced 6,000 pounds of thrust in vacuum.
The Orbiter was also configured with a reusable thermal protection system (TPS) which consisted of silica tiles and reinforced carbon-carbon material. The TPS for all previous manned space vehicles utilized single-use ablators. Would the new TPS work? How robust would it be in flight? What post-flight care would be needed? Answers would come only through flight.
To add to the “excitement” of first flight, the Orbiter was a winged vehicle and would therefore perform a hypersonic lifting entry. The vehicle energy state would have to be managed perfectly over the 5,000 mile reentry flight path from entry interface to runway touchdown. Since the Orbiter flew an unpowered entry, it would land dead-stick. There would only be one chance to land.
On Sunday,12 April 1981, the Space Shuttle Columbia lifted-off from Pad 39A at Cape Canaveral, Florida. Official launch time was 12:00:03 UTC. The flight crew consisted of Commander John W. Young and Pilot Robert L. Crippen. Their Columbia launch stack tipped the scales at 4.5 million pounds and thundered away from the pad on over 7 million pounds of thrust.
Columbia went through maximum dynamic pressure (606 psf) at Mach 1.06 and 26.5 KFT. SRB separation occurred 120 seconds into flight at Mach 3.88 and 174,000 feet; 10,000 feet higher than predicted. This lofting of the ascent trajectory was later attributed to unmodeled plume-induced aerodynamic effects in the Orbiter and ET base region.
Following separation, Columbia rode the ET to burnout at Mach 21 and 389.7 KFT. Following ET separation, Columbia’s OMS engines were fired minutes later to achieve a velocity of 17,500 mph and a 166-nautical mile orbit.
Young and Crippen would orbit the Earth 37 times before coming home on Tuesday, 14 April 1981. In doing so, they successfully flew the first hypersonic lifting reentry from orbit. Though unaware of it at the time, the crew came very close to catastrophe as the Orbiter’s body flap had to be deflected 8 degrees more than predicted to maintain hypersonic pitch control.
The reason for this “hypersonic anomaly” was that ground test and aero modeling had failed to capture the effects of high temperature gas dynamics on Orbiter pitch aerodynamics. Specifically, the vehicle was more stable in hypersonic flight than had been predicted. This necessitated greater nose-down body flap deflections to trim the vehicle in pitch. It was a close-call. But Columbia and its crew lived to fly another day.
Columbia touched-down at 220 mph on Runway 23 at Edwards Air Force Base, California at 18:20:57 UTC. Young and Crippen were euphoric with the against-the-odds success of the Space Shuttle’s first mission.
NASA too reveled in the Shuttle’s accomplishment. And so did America. This was the country’s first manned space mission since 1975. The longest period of manned spaceflight inactivity ever in the Nation’s history.
Fittingly, a well-known national news magazine celebrated Columbia’s success with a headline which read: “America is Back!”
And while it flies no more, we remember that first Orbiter, its first flight and its many subsequent accomplishments. To which we say: Hail Columbia!
Twenty-years ago today, the Orbital Sciences Corporation (OSC) orbited a PegSat satellite using the then-new Pegasus 3-stage launch vehicle. This historic event marked the first successful implementation of the air-launched satellite launcher concept.
The concept of air-launch dates back to the 1940’s and the early days of United States X-plane flight research. A multi-engine aircraft known as the mothership was employed to transport a smaller test aircraft to altitude. The test aircraft was subsequently dropped from the mothership and went on to conduct the flight research mission.
A clear benefit of air-launch was that all of the fuel and propulsion required to get to the drop point was provided by the mothership. Thus, the test aircraft was allowed to use all of its own fuel for the flight research mission proper. In that sense, the mothership-test aircraft combination functioned as a two-stage launch vehicle.
The value and efficacy of the air-launch concept was demonstrated on numerous X-plane programs. Flight research aircraft such as the Bell XS-1, Bell X-1A, Bell X-1E, Bell X-2, Douglas D-558-II, and North American X-15 were all air-launched. More recently, the X-43A and X-51A scramjet-powered flight research vehicles also employed the air-launch concept.
An added benefit of the air-launch technique is that the launch site is highly portable! This provides enhanced mission flexibility compared to fixed position launch sites. The associated operating costs are much lower for the air-launched concept as well.
Orbital Science’s original Pegasus launch vehicle configuration was designed to fit within the dimensional envelope of the X-15. The standard Pegasus configuration measured 50 feet in length and had a wingspan of 22 feet. The same dimensions as the baseline X-15 rocket airplane. Pegasus body diameter and launch weight were 50 inches and 41,000 pounds, respectively.
A key design feature of the Pegasus 3-stage launch vehicle configuration was the vehicle’s trapezodal-planform wing which provided the aerodynamic lift required to shape the endoatmospheric portion of the ascent flight path. This made Pegasus even more X-15-like.
The real difference between Pegasus and the X-15 was propulsion. The X-15 performed a sub-orbital mission using an XLR-99 liquid rocket engine rated at 57,000 pounds of sea level thrust. Pegasus used a combination of three (3) Hercules solid rocket motors to perform an orbital mission. The 1st, 2nd and 3rd stage rocket motors were rated at 109,000, 26,600 and 7,800 pounds of vacuum thrust, respectively.
On Thursday, 05 April 1990, the first Pegasus launch took place over the Pacific Ocean within an area known as the Point Arguello Western Air Drop Zone (WADZ) . Pegasus 001 fell away from its NASA B-52B (S/N 52-0008) mothership at 19:10 UTC as the pair flew at Mach 0.8 and 43,000 feet. Pegasus first stage ignition took place 5 seconds after drop.
Following first stage ignition, the Pegasus executed a pull-up to begin the trip upstairs. The second and third stage rocket motors fired on time. The stage separation and payload fairing jettison events worked as planned. Roughly 10 minutes after drop, the 392-pound PegSat payload arrived in a 315 mile x 249 mile elliptical orbit.
Since that triumphant day in April 1990, both the Pegasus launch vehicle configuration and mission have grown and matured. Of a total of 40 official Pegasus missions to date, 37 have been flown successfully.
Thirty-nine years ago today, the USAF/NASA X-24A lifting body was flown to a speed of 1,036 mph (Mach 1.6) by NASA Research Pilot John Manke. It was the fastest flight of the rocket-powered lifting body.
A lifting body is an unconventional aircraft in that the vehicle generates lift without the benefit of a wing. Rather, the aircraft produces lift by the manner in which its fuselage is shaped.
In the early days of manned spaceflight, there were two schools of thought regarding the preferred mode of entry from orbital flight. One camp favored ballistic entry where the predominant flight force was aerodynamic drag. This was in contradistinction to lifting entry where both aerodynamic lift and drag forces were generated.
Ballistic entry is the more simple approach, but affords little control of the endoatmospheric flight path. This stems from the fact that the landing point for a ballistic entry is largely dictated by the entry vehicle’s velocity and flight path angle at entry interface.
While operationally more complicated, lifting entry provides a positive means for controlling the entry vehicle’s flight path and thus its landing point. At hypersonic speeds, even a small amount of lift markedly enhances entry vehicle downrange and crossrange capability.
Part of the complication of designing a lifting entry vehicle stems from the need to deal with high levels of heating during entry flight. The vehicle’s shape not only dictates its aerodynamic capabilities, but its aerodynamic heating characteristics as well. Thus, issues of flight path control and airframe survivability are interrelated.
The heyday of lifting body flight research spans the period from 1963 to 1975. For the record, the lifting bodies flown in that era include the following vehicles: M2-F1, M2-F2, M2-F3, HL-10, X-24A and X-24B. Each of these aircraft were piloted. All lifting body flight research was conducted at Edwards Air Force Base, California.
The X-24A was developed by the Martin Company under contract to the United States Air Force. A single X-24A was produced. It measured 24.5 feet in length and had a gross weight of 11,450 pounds. Airframe empty weight was 6,300 pounds.
Though unconventional in shape, the X-24A incorporated full 3-axis flight controls. The aircraft was powered by the venerable XLR-11 rocket motor. This four-chambered propulsion system was rated at 8,500 pounds of sea level thrust. Maximum burn time was on the order of 140 seconds. All landings were conducted deadstick.
The X-24A displayed generally good handling characteristics, but had to be flown precisely. Angle-of-attack had to be maintained between about 4 and 12 degrees. Flight at lower and higher angles-of-attack encountered undesirable aerodynamic control and cross-coupling characteristics.
On Monday, 29 March 1971, X-24A (S/N 66-13551) fell away from the B-52B mothership in an effort to fly a maximum speed mission. NASA research pilot John Manke was at the controls. Manke accelerated the aircraft in a climb and reached a record speed of 1,036 mph (Mach 1.6). Interestingly, it was John Manke who had previously flown the X-24A to its highest altitude of 71,407 feet on 27 October 1970.
The X-24A, like all of the lifting bodies, contributed significantly to the decision to land the Space Shuttle Orbiter deadstick. The lifting bodies, as well as X-aircraft such as the X-1, X-2, and X-15, proved conclusively that an aircraft could reliably (1) manage its energy state and (2) precisely control touchdown point in an unpowered state.
The X-24A flew a total of 28 flight research missions. Following its final flight, the X-24A was then converted to the radically different-appearing X-24B configuration which flew 36 times. Today, the X-24B is displayed in a place of honor in the United States Air Force Museum at Wright-Patterson Air Force Base in Dayton, Ohio.
Forty-five years ago this week, Gemini III was launched into Earth orbit with astronauts Vigil I. Grissom and John W. Young onboard. The 3-orbit mission marked the first time that the United States flew a multi-man spacecraft.
Project Mercury was America’s first manned spaceflight series. Project Apollo would ultimately land men on the Moon and return them safely to the Earth. In between these historic spaceflight efforts would be Project Gemini.
The purpose of Project Gemini was to develop and flight-prove a myriad of technologies required to get to the Moon. Those technologies included spacecraft power systems, rendezvous and docking, orbital maneuvering, long duration spaceflight and extravehicular activity.
The Gemini spacecraft weighed 8,500 pounds at lift-off and measured 18.6 feet in length. Gemini consisted of a reentry module (RM), an adapter module (AM) and an equipment module (EM).
The crew occupied the RM which also contained navigation, communication, telemetry, electrical and reentry reaction control systems. The AM contained maneuver thrusters and the deboost rocket system. The EM included the spacecraft orbit attitude control thrusters and the fuel cell system. Both the AM and EM were used in orbit only and discarded prior to entry.
Gemini-Titan III (GT-3) lifted-off at 14:24 UTC from LC-19 at Cape Canaveral, Florida on Tuesday, 23 March 1965. The two-stage Titan II launch vehicle placed Gemini 3 into a 121 nautical mile x 87 nautical mile elliptical orbit.
Gemini 3’s primary objective was to put the maneuverable Gemini spacecraft through its paces. While in orbit, Grissom and Young fired thrusters to change the shape of their orbital flight path, shift their orbital plane, and dip down to a lower altitude. Gemini 3 was also the first time that a manned spacecraft used aerodynamic lift to change its entry flight path.
As spacecraft commander, Gus Grissom named his cosmic chariot The Molly Brown in reference to a then-popular Broadway show; “The Unsinkable Molly Brown”. Grissom chose the moniker in memory of his first spaceflight experience wherein his Liberty Bell 7 Mercury spacecraft sunk in almost 17,000 feet of water during post-splashdown operations.
At almost two (2) hours into the mission, pilot John Young presented Grissom with his favorite sandwich which had been smuggled onboard. Grissom and Young took a bite of the corned beef sandwich and put it away since loose crumbs could get into spacecraft electronics with catastrophic results. Not amused, NASA management reprimanded the crew after the mission.
Gemini 3 splashed-down in the Atlantic Ocean at 19:16:31 UTC following a 3 orbit mission. The spacecraft landed 45 nautical miles short of the intended splashdown point due to a misprediction of aerodynamic lift. Although hot and sea-sick, Grissom refused to open the spacecraft hatches until the recovery ship USS Intrepid came on station.
Nine (9) additional Gemini space missions would follow the flight of Gemini 3. Indeed, the historical record shows that the Gemini Program would fly an average of every two (2) months by the time Gemini XII landed in December 1966. During that period, the United States would take the lead in the race to the Moon that it would never relinquish.
Fifty-two years ago this week, the United States Navy Vanguard Program registered its first success with the orbiting of the Vanguard 1 satellite. The diminutive orb was the fourth man-made object to be placed in Earth orbit.
The Vanguard Program was established in 1955 as part of the United States involvement in the upcoming International Geophysical Year (IGY). Spanning the period between 01 July 1957 and 31 December 1958, the IGY would serve to enhance the technical interchange between the east and west during the height of the Cold War.
The overriding goal of the Vanguard Program was to orbit the world’s first satellite sometime during the IGY. The satellite was to be tracked to verify that it achieved orbit and to quantify the associated orbital parameters. A scientific experiment was to be conducted using the orbiting asset as well.
Vanguard was managed by the Naval Research Laboratory (NRL) and funded by the National Science Foundation (NSF). This gave the Vanguard Program a distinctly scientific (rather than military) look and feel. Something that the Eisenhower Administration definitely wanted to project given the level of Cold War tensions.
The key elements of Vanguard were the Vanguard launch vehicle and the Vanguard satellite. The Vanguard 3-stage launch vehicle, manufactured by the Martin Company, evolved from the Navy’s successful Viking sounding rocket. The Vanguard satellite was developed by the NRL.
On Friday, 04 October 1957, the Soviet Union orbited the world’s first satellite – Sputnik I. While the world was merely stunned, the United States was quite shocked by this achievement. A hue and cry went out across the land. How could this have happened? Will the Soviets now unleash nuclear weapons on us from space? And most hauntingly – where is our satellite?
In the midst of scrambling to deal with the Soviet’s space achievement, America would receive another blow to the national solar plexus on Sunday, 03 November 1957. That is the day that the Soviet Union orbited their second satellite – Sputnik II. And this one even had an occupant onboard; a mongrel dog name Laika.
The Vanguard Program was uncomfortably in the spotlight now. But it really wasn’t ready at that moment to be America’s response to the Soviets. After all, Vanguard was just a research program. While the launch vehicle was developing well enough, it certainly was not ready for prime time. The Vanguard satellite was a new creation and had never been used in space.
History records that the first American satellite launch attempt on Friday, 06 December 1957 went very badly. The launch vehicle lost thrust at the dizzying height of 4 feet above the pad, exploded when it settled back to Earth and then consumed itself in the resulting inferno. Amazingly, the Vanguard satellite survived and was found intact at the edge of the launch pad.
Faced with a quickly deteriorating situation, America desperately turned to the United States Army for help. Wernher von Braun and his team at the Army Ballistic Missile Agency (ABMA) responded by orbiting Explorer I on Friday, 31 January 1958. America was now in space!
The Vanguard Program regrouped and attempted to orbit a Vanguard satellite on Wednesday, 05 February 1958. Fifty-seven seconds into flight the launch vehicle exploded. Vanguard was now 0 for 2 in the satellite launching game. Undeterred, another attempt was scheduled for March.
Monday, 17 March 1958 was a good day for the Vanguard Program and the United States of America. At 12:51 UTC, Vanguard launch vehicle TV-4 departed LC-18A at Cape Canaveral, Florida and placed the Vanguard I satellite into a 2,466-mile x 406-mile elliptical orbit. On this Saint Patrick’s Day, Vanguard registered its first success and America had a second satellite orbiting the Earth.
Whereas the Soviet satellites weighed hundreds of pounds, Vanguard I was tiny. It was 6.4-inches in diameter and weighed only 3.25 pounds. Soviet Premier Nikita Khrushchev mockingly referred to it as America’s “grapefruit satellite”. Small maybe, but mighty as well. Vanguard I went on to record many discoveries that helped write the book on spaceflight.
Khrushchev is gone and all of those big Sputniks were long ago incinerated in the fire of reentry. Interestingly, the “grapefruit satellite” is still in space and is the oldest satellite in Earth orbit. Vanguard I has completed roughly 200,000 Earth orbits and traveled 5.7 billion nautical miles since 1957. It is expected to stay in orbit for another 200 years. Not bad for a grapefruit.
Thirty-nine years ago this month, a pair of SPRINT ABM interceptors fired from the Kwajalein Missile Range intercepted a reentry vehicle launched from Vandenberg Air Force Base, California. It was the first salvo launch of the legendary hypersonic interceptor.
The Safeguard Anti-Ballistic Missile (ABM) System was developed between the mid-960’s and mid-1970’s to protect United States ICBM sites. Safeguard consisted of an exoatmospheric missile (Spartan) and an endoatmospheric interceptor (SPRINT). In today’s missile defense paralance, we would refer to these vehicles as mid-course and terminal phase interceptors, respectively.
The 3-stage Spartan measured 55 feet in length, weighed 28,700 pounds at launch and had a range of 465 miles. Vehicle maximum velocity was in excess of 4,000 ft/sec. Spartan was armed with a 5-megaton nuclear warhead. Target destruction was effected via neutron flux.
The Solid Propellant Rocket INTerceptor (SPRINT) missile was a 2-stage vehicle. It measured 27 feet in length, weighed 7,500 pounds at launch and had a maximum range of 25 miles. SPRINT was configured with a nuclear warhead that had a yield on the order of several kilotons. Target destruction was also via radiation kill.
SPRINT’s performance was astounding by any measure. One second after first stage rocket motor ignition, the vehicle was already a mile away from the launch site. The Mach 5 stage separation event occurred a little over 1.2 seconds from first stage ignition.
The SPRINT upper stage saw a peak acceleration of 100 g’s and reached Mach 10 in about 6 seconds. Maximum mission duration was 15 seconds.
SPRINT’s rapid velocity build-up produced a correspondingly rapid rise in the vehicle’s surface temperature due to aerodynamic heating. The second stage glowed incandescently in daylight as its surface temperature exceeded that of an acetylene torch. The severe thermal state also resulted in the shock layer flow near the missile’s surface becoming a partially-ionized plasma.
SPRINT electromechanical and electronic equipment had to be ruggedized to handle the extreme shock, vibration, and acceleration environment of flight. In addition, the vehicle was hardened to withstand the severe pressure and electromagnetic pulses associated with a thermonuclear warhead detonation.
SPRINT flight testing started at White Sands Missile Range (WSMR) in November of 1965. Devoted to SPRINT subsystem testing, the WSMR flight test campaign ended in August 1970 and consisted of 42 shots.
Overall Safeguard system testing was conducted at the Kwajalein Missile Range (KMR) beginning in 1970 and extended through 1973. The KMR flight test program consisted of 34 flight tests. The first successful SPRINT intercept of a reentry vehicle took place in December 1970.
On Wednesday, 17 March 1971, SPRINT interceptors FLA-49 and FLA-50 were launched in salvo from Meck Island located on the eastern edge of the Kwajalein Atoll. The target for this mission was a Minuteman I reentry vehicle launched 4,800 miles to the east at Vandenberg Air Force Base. The target was successfully engaged and destroyed.
In October of 1974, a single Safeguard System unit became operational at Grand Forks Air Force Base, North Dakota. Interestingly, by February 1976, this lone deployed unit would be permanently deactivated. Thus ended the Safeguard ABM Program. A combination of high costs, questionable efficacy, lack of congressional support and international politics accounted for its very brief operational life.
Fifty-one years ago this week, NASA’s Pioneer 4 probe flew within 37,000 miles of the lunar surface. In doing so, the spacecraft flew the first successful American lunar flyby mission.
The Pioneer Program was a series of planetary space missions conducted by NASA between 1958 and 1978. The target of the early missions (1958-1960) was the Moon. The one exception was Pioneer 5 which investigated the interplanetary medium between Earth and Venus. Later Pioneer mission (1965-1978) were devoted to investigation of Jupiter and Saturn.
It was tough sledding in the early days of the Pioneer Program where the primary goal was to orbit the Moon. However, launch vehicle reliability was simply too poor and space trajectory control too crude to meet the lunar orbit goal in the lat 1950’s.
Indeed, none of the ten (10) Pioneer missions flown in the 1958-1960 period managed to achieve a lunar orbit of any kind. Interestingly, the United States would not orbit a spacecraft around the Moon until the Lunar Orbiter 1 mission in August of 1966.
While the lunar orbit goal proved too daunting for the early Pioneer Program, a lunar flyby mission was feasible using extant technology. The flyby mission simply required the spacecraft to sweep by the Moon (without impacting the surface) as the probe moved along an interplanetary trajectory towards the Sun. Ultimately, the spacecraft would find itself in solar orbit.
The Pioneer 4 spacecraft was a cone 20-inches in length and 9-inches in diameter. It weighed a mere 13.5 pounds. Spin-stabilization was effected by spinning the vehicle at 400 rpm about its longitudinal axis. Instrumentation was sparse; just a photoelectric sensor and a pair of radiation sensors.
On Tuesday, 03 March 1959, a Juno II launch vehicle carrying the Pioneer 4 spacecraft lifted-off from Cape Canaveral, Florida at 1711 UTC. The 4-stage Juno II was a modification of the Juno I launch vehicle that orbited America’s first satellite (Explorer 1) on Friday, 31 January 1958.
Pioneer 4 was successfully placed into an interplanetary trajectory that saw the probe pass within 37,000 miles of the lunar surface at 22:25 UTC on Wednesday, 04 March 1959. Considering that the Moon is about 238,000 miles from Earth, the flyby wasn’t all that close. However, at the dawn of the space age, it was indeed a significant accomplishment.
Pioneer 4 was powered by mercury batteries; that is, the spacecraft did not use solar cells. Sensor measurements were telemetered back to Earth at 960.05 MHz via a 0.1-Watt transmitter. Earth-based stations tracked the space probe out to a distance of roughly 407,000 miles from Earth.
At 01:00 UTC on Wednesday, 18 March 1959, Pioneer 4 reached the closest point in its eternal orbit about the Sun. Having done so, Pioneer 4 would forever hold the distinction of being the first American spacecraft to transit interplanetary space and reach heliocentric orbit.
Sixty-one years ago this week, a United States two-stage liquid-fueled rocket reached a then-record altitude of 250 miles. Launch took place from Pad 33 at White Sands Proving Ground (WSPG), New Mexico.
The Bumper Program was a United States Army effort to reach flight altitudes and velocities never before achieved by a rocket vehicle. The name “Bumper” was derived from the fact that the lower stage would act to “bump” the upper stage to higher altitude and velocity than it (i.e., the upper stage) was able to achieve on its own.
The Bumper Program, which was actually part of the Army’s Project Hermes, officially began on Friday, 20 June 1947. The project team consisted of the General Electric Company, Douglas Aircraft Company and Cal Tech’s Jet Propulsion Laboratory. A total of eight (8) test flights took place between May 1948 and July 1950.
The Bumper two-stage configuration consisted of a V-2 booster and a WAC Corporal upper stage. The V-2’s had been captured from Germany following World War II while the WAC Corporal was a single stage American sounding rocket. The launch stack measured 62 feet in length and weighed around 28,000 pounds.
Propulsion-wise, the V-2 booster generated 60,000 pounds of thrust with a burn time of 70 seconds. The WAC Corporal rocket motor produced 1,500 pounds of thrust and had a burn time of 47 seconds.
The flight of Bumper-WAC No. 1 occurred on Thursday, 13 May 1948. This was an engineering test flight in which the WAC Corporal achieved a peak altitude of 79 miles. Unfortunately, the next three (3) flights were plagued by development problems of one kind or another and failed to achieve an altitude of even 10 miles.
Bumper-WAC No. 5 was fired from WSPG on Thursday, 24 February 1949. The V-2 burned-out at an altitude of 63 miles and a velocity of 3,850 feet per second. The WAC Corporal accelerated to a maximum velocity of 7,550 feet per second and then coasted to an apogee of 250 miles.
With generation of a very thin bow shock layer and high aerodynamic surface heating levels, the flight of Bumper-WAC No. 5 can be considered as the first time a man-made flight vehicle entered the realm of hypersonic flight. Notwithstanding that achievement, its maximum Mach number of 7.6 would be eclipsed in July of 1950 when Bumper-WAC No. 7 reached Mach 9.
Three (3) more Bumper-WAC missions would follow Bumper-WAC No.5. While Bumper-WAC No. 6 would fly from WSPG, the final two (2) missions were conducted from an isolated Florida launch site in July of 1950.
The hot, bug-infested Floridian launch location, springing-up amongst sand dunes and scrub palmetto, would one day become the seat of American spaceflight. It was known then as the Joint Long-Range Proving Ground. Today, we know it as Cape Canaveral.
The Bumper Program successfully demonstrated the efficacy of the multi-staging concept. Bumper also provided valuable flight experience in stage separation and high altitude rocket motor ignition systems. In short, Bumper played a vital role in helping America successfully develop its ICBM, satellite and manned spaceflight capabilities.
While its historical significance, and even its existence, has been lost to many here in the 21st Century, the Bumper Program played a major role in our quest for the Moon. As such, it will forever hold a hollowed place in the annals of United States aerospace history.
Two years ago this month, a United States Navy STANDARD Missile SM-3 Block IA intercepted and destroyed a failed NRO satellite at an altitude of 133 nautical miles. The relative velocity at intercept was in excess of 22,000 mph.
The United States Navy/Raytheon Missile Systems SM-3 (RIM-161) is the sea-based arm of the Missile Defense Agency’s Ballistic Missile Defense System (BMDS). The 3-stage missile carries a Kinetic Warhead (KW) that provides an exoatmospheric hit-to-kill capability.
In order to ensure a lethal hit, the SM-3 KW guides to a specific aimpoint on the target’s airframe. The ability to reliably do so has been impressively demonstrated in a series of intercept flight tests that began in 2002.
SM-3 rounds are launched from the MK-41 Vertical Launcher System (VLS) aboard United States Navy cruisers and destroyers. The at-sea basing concept provides for a high degree of operational flexibility in the ballistic missile intercept mission.
The Lockheed Martin-built USA-193 was launched on a classified mission from California’s Vandenberg Air Force Base (VAFB) at 2100 UTC on Thursday, 14 December 2006. Shortly after reaching orbit, contact with the 5,000-lb satellite was lost.
By January 2008, USA-193’s orbit had decayed to such an extent that its reentry appeared imminent. Such events raise concerns for the safety of those on Earth who reside within the debris impact footprint. However, there was an additional concern in the case of USA-193. The satellite still had about 1,000-lbs of hydrazine onboard.
Should the USA-193 hydrazine tank survive reentry, those living in the impact area would be exposed to a highly toxic cloud of the volatile substance. Officials concluded that the safest thing to do was to destroy the satellite before it reentered the atmosphere.
On Thursday, 21 February 2008, the USS Lake Erie was on station in the Pacific Ocean west of Hawaii. The US Navy cruiser fired a single SM-3 interceptor at 0326 UTC. Minutes later, the missile’s KW took out the satellite and dispersed its hydrazine load into space. Mission accomplished!
In the aftermath of the satellite take-down, Russia and others predictably accused the United States of using the USA-193 hydrazine issue as an excuse to demonstrate SM-3’s anti-satellite capability. While such capability was indeed demonstrated, noteworthy is the fact that all systems modified to execute the satellite intercept have subsequently been returned to a ballistic missile defense posture.
Forty-eight years ago this month, Project Mercury Astronaut John H. Glenn, Jr. became the first American to orbit the Earth. Glenn’s spacecraft name and mission call sign was Friendship 7.
Mercury-Atlas 6 (MA-6) lifted-off from Cape Canaveral’s Launch Complex 14 at 14:47:39 UTC on Tuesday, 20 February 1962. It was the first time that the Atlas LV-3B booster was used for a manned spaceflight.
Three-hundred and twenty seconds after lift-off, Friendship 7 achieved an elliptical orbit measuring 143 nm (apogee) by 86 nm (perigee). Orbital inclination and period were 32.5 degrees and 88.5 minutes, respectively.
The most compelling moments in the United States’ first manned orbital mission centered around a sensor indication that Glenn’s heatshield and landing bag had become loose at the beginning of his second orbit. If true, Glenn would be incinerated during entry.
Concern for Glenn’s welfare persisted for the remainder of the flight and a decision was made to retain his retro package following completion of the retro-fire sequence. It was hoped that the 3 straps holding the retro package would also hold the heatshield in place.
During Glenn’s return to the atmosphere, both the spent retro package and its restraining straps melted in the searing heat of re-entry. Glenn saw chunks of flaming debris passing by his spacecraft window. At one point he radioed, “That’s a real fireball outside”.
Happily, the spacecraft’s heatshield held during entry and the landing bag deployed nominally. There had never really been a problem. The sensor indication was found to be false.
Friendship 7 splashed-down in the Atlantic Ocean at a point 432 nm east of Cape Canaveral at 19:43:02 UTC. John Glenn had orbited the Earth 3 times during a mission which lasted 4 hours, 55 minutes and 23 seconds. Within short order, spacecraft and astronaut were successfully recovered aboard the USS Noa.
John Glenn became a national hero in the aftermath of his 3-orbit mission aboard Friendship 7. It seemed that just about every newspaper page in the days following his flight carried some sort of story about his historic fete. Indeed, it is difficult for those not around back in 1962 to fully comprehend the immensity of Glenn’s flight in terms of what it meant to the United States.
John Herschel Glenn, Jr. will turn 89 on 18 July 2010. His trusty Friendship 7 spacecraft is currently on display at the Smithsonian National Air and Space Museum in Washington, DC.
Thirty-five years ago today, an USAF F-15A Eagle reached an altitude of 30 km (98,425 feet) 207.8 seconds from brake release. The pilot for the record-breaking mission was USAF Major Roger Smith.
Operation Streak Eagle was a mid-1970’s effort by the United States Air Force to set eight (8) separate time-to-climb records using the McDonnell-Douglas F-15 Air Superiority Fighter. These record-setting flights originated from Grand Forks Air Force Base in North Dakota.
Starting on Thursday, 16 January 1975, the 19th pre-production F-15 Eagle aircraft (S/N 72-0119) was used to establish the following time-to-climb records during Operation Streak Eagle:
3 km, 16 January 1975, 27.57 seconds, Major Roger Smith
6 km, 16 January 1975, 39.33 seconds, Major Willard Macfarlane
9 km, 16 January 1975, 48.86 seconds, Major Willard Macfarlane
12 km, 16 January 1975, 59.38 seconds, Major Willard Macfarlane
15 km, 16 January 1975, 77.02 seconds, Major David Peterson
20 km, 19 January 1975, 122.94 seconds, Major Roger Smith
25 km, 26 January 1975, 161.02 seconds, Major David Peterson
The eighth and final time-to-climb record attempt of Operation Streak Eagle took place on Saturday, 01 February 1975. The goal was to set a new time-to-climb record to 30 km. The pilot was required to wear a full pressure suit for this mission.
At a gross take-off weight of 31,908 pounds, the Streak Eagle aircraft had a thrust-to-weight ratio in excess of 1.4. The aircraft was restrained via a hold-down device as the two Pratt and Whitney F100 turbofan engines were spooled-up to full afterburner.
Following hold-down and brake release, the Streak Eagle quickly accelerated during a low level transition following take-off. At Mach 0.65, Smith pulled the aircraft into a 2.5-g Immelman. The Streak Eagle completed this maneuver 56 seconds from brake release at Mach 1.1 and 9.75 km. Rolling the aircraft upright, Smith continued to accelerate the Streak Eagle in a shallow climb.
At an elapsed time of 151 seconds and with the aircraft at Mach 2.2 and 11.3 km, Smith executed a 4-g pull to a 60-degree zoom climb. The Steak Eagle passed through 30 km at Mach 0.7 in an elapsed time of 207.8 seconds. The apex of the zoom trajectory was about 31.4 km. With a new record in hand, Smith uneventfully recovered the aircraft to Grand Forks AFB.
Operation Streak Eagle ended with the capturing of the 30 km time-to-climb record. In December 1980, the aircraft was retired to the USAF Museum at Wright-Patterson Air Force Base in Dayton, Ohio. It is currently held in storage at the Museum and no longer on public display.
Twenty-four years ago this week, the seven member crew of STS-51L were killed when the Space Shuttle Challenger disintegrated 73 seconds after launch from LC-39B at Cape Canaveral, Florida. It was the first fatal in-flight accident in American spaceflight history.
In remarks made at a memorial service held for the Challenger Seven in Houston, Texas on Friday, 31 January 1986, President Ronald Wilson Reagan expressed the following sentiments:
“The future is not free: the story of all human progress is one of a struggle against all odds. We learned again that this America, which Abraham Lincoln called the last, best hope of man on Earth, was built on heroism and noble sacrifice. It was built by men and women like our seven star voyagers, who answered a call beyond duty, who gave more than was expected or required and who gave it little thought of worldly reward.”
We take this opportunity now to remember the heroic fallen:
Francis R. (Dick) Scobee, Commander
Michael John Smith, Pilot
Ellison S. Onizuka, Mission Specialist One
Judith Arlene Resnik, Mission Specialist Two
Ronald Erwin McNair, Mission Specialist Three
S.Christa McAuliffe, Payload Specialist One
Gregory Bruce Jarvis, Payload Specialist Two
Speaking for his grieving countrymen, President Reagan closed his eulogy with these words:
“Dick, Mike, Judy, El, Ron, Greg and Christa – your families and your country mourn your passing. We bid you goodbye. We will never forget you. For those who knew you well and loved you, the pain will be deep and enduring. A nation, too, will long feel the loss of her seven sons and daughters, her seven good friends. We can find consolation only in faith, for we know in our hearts that you who flew so high and so proud now make your home beyond the stars, safe in God’s promise of eternal life.”
Tuesday, 28 January 1986. We Remember.
One year ago this month, US Airways Flight 1549 successfully ditched in the Hudson River following loss of thrust in both turbofan engines. Incredibly, all 155 passengers and crew members survived.
US Airways Flight 1549 lifted-off from Runway 4 of New York’s LaGuardia Airport at 18:25:56 UTC on Thursday, 15 January 2009. The Airbus 320-214 (N106US) was making its 16,299th flight. Call sign for the day’s flight was Cactus 1549.
Captain Chesley B. Sullenberger III and First Officer Jeffrey B. Skiles were in the cockpit of Cactus 1549. Donna Dent, Doreen Welsh and Sheila Dail served as flight attendants. Together, these crew members were responsible for the lives of 150 airline passengers.
Following a normal take-off, Cactus 1549 collided with a massive flock of Canadian Geese climbing through 3,000 feet. Numerous bird strikes were experienced. Most critically, both CFM56-5B4/P turbofan engines suffered bird ingestion. As Captain Sullenberger suscinctly described it later, the result was “sudden, complete, symmetrical” loss of thrust.
Quickly assessing their predicament, Captain Sullenberger instinctively knew that he could not get his aircraft back to a land-based runway. He was flying too low and slow to make such an attempt. He would have to ditch his 150,000-pound aircraft in the nearest waterway; the Hudson River.
The story of what ensued following loss of thrust is best told by Captain Sullenberger himself. The reader is therefore directed to chapters 13 and 14 of his post-mishap book entitled “Highest Duty”. The bottom line is that the aircraft was successfully ditched in the Hudson River roughly three and half minutes after loss of thrust.
Once the aircraft was on the water, the crew members evacuated all 150 passengers in less than 4 minutes. People either got into life rafts or stood on the aircraft’s wings. It was very cold. Air temperature was 21F with a windchill factor of 11F. The water temperature registered at 36F.
First responders from the New York Waterway quickly came to the aid of Cactus 1549. A total of fourteen vessels responded to the emergency with the first boat arriving within four minutes of the aircraft coming to a stop.
Many selfless acts of compassion and exemplary displays of valor were observed during Cactus 1549 rescue operations. This was true for those amongst the ranks of the rescuers and rescued alike.
Happily and to the great relief of the US Airways flight crew, there was no loss of life resulting from the emergency ditching of Cactus 1549. Now known as “The Miracle on the Hudson”, the events of that harrowing experience on a winter day in NYC will be forever remembered in the annals of aviation.
For their professional efforts in handling the Cactus 1549 in-flight emergency, Chesley Sullenberger, Jeff Skiles, Donna Dent, Doreen Welsh and Sheila Dail received the rarely-awarded Guild of Air Pilots and Air Navigators Master’s Medal on Thursday, 22 January 2009.
In part, the Master’s Medal citation read: “The reactions of all members of the crew, the split second decision making and the handling of this emergency and evacuation was ‘text book’ and an example to us all. To have safely executed this emergency ditching and evacuation, with the loss of no lives, is a heroic and unique aviation achievement.”
To which we say: Amen!
Forty-two years ago this month, a XSM-64 Navaho G-26 flight test vehicle flew 1,075 miles in 40 minutes at a sustained speed of Mach 2.8. It was the 8th flight test of the ill-fated Navaho Program.
The post-World War II era saw the development of a myriad of missile weapons systems. Perhaps the most influential and enigmatic of these systems was the Navaho missile.
Navaho was intended as a supersonic, nuclear-capable, strategic weapon system. It consisted of two (2) stages. The first stage was rocket-powered while the second stage utilized ramjet propulsion. The aircraft-like second stage was configured with a high lift-to-drag airframe in order to achieve strategic reach.
While there were a number of antecedants dating back to 1946, the Navaho Program really began in 1950 as Weapon System 104A. The requirements included a range of 5,500 miles, a minimum cruise speed of Mach 3 and a minimum cruise altitude of 60,000 feet. The payload included an ordnance load of 7,000 pounds delivered within a CEP of 1,500 feet.
North American Aviation (NAA) proposed a 3-phase development plan for WS-104A. Phase 1 involved testing of the missile alone (the X-10) up to Mach 2. Phase 2 covered the testing of the two-stage launch vehicle (the G-26) up to Mach 2.75 and a range of 1,500 miles. Phase 3 would be the ultimate near-production vehicle (the G-38). Only Phase 1 and Phase 2 testing took place.
The Navaho missile-booster vehicle measured 84 feet in length and weighed about 135,000 pounds at lift-off. The launch weight for the booster was 75,000 pounds; most of which was due to the alcohol and LOX propellants. The missile empty weight was 24,000 pounds.
On Friday, 10 January 1958, Navaho G-26 No. 9 (54-3098) lifted-off from LC-9 at Cape Canaveral, Florida. Climbing out under 240,000 pounds of thrust from its dual Rocketdyne XLR71-NA-1 rocket motors, missile-booster separation occurred at Mach 3.15 and 73,000 feet. Following air-start and take-over of twin Wright XRJ47-W-5 ramjets, generating a combined thrust of 16,000 pounds, the Navaho missile initiated a near triple-sonic cruise toward the Puerto Rico target area.
As the Navaho missile approached the environs of Puerto Rico, the vehicle was commanded to initiate a sweeping right-hand turn back towards the Cape. Unfortunately, the right intake experienced an unstart and a concommitant, asymmetric loss of thrust. Underpowered and without a restart capability, the vehicle was subsequently commanded to execute a dive into the Atlantic.
Flight No. 8, although only partially successful, flew longer and farther than any Navaho flight test vehicle. Only G-26 Flight No. 6 flew faster (Mach 3.5).
Although three (3) flights would follow G-26 Flight No. 8, all would suffer failure of one kind or another. In point of fact, the Navaho Program had been canceled on Saturday, 13 July 1957. The final six (6) Navaho flights were simply an attempt to extract the most from the remaining missile-booster rounds. Over 15,000 NAA employees lost their jobs the day Navaho died.
Navaho was cancelled primarily due to the ascendancy of the Intercontinental Ballistic Missile (ICBM). Very simply, an ICBM could deliver nuclear ordnance farther, faster and more accurately than a winged, unstealthy strategic missile. Navaho’s relatively numerous technical issues and programmatic delays simply served to drive the final nail into a long-prepared coffin.
While few today remember or even know of the Navaho Program, its technology has had a profound influence on all manner of aerospace vehicles up to the present day. Interestingly, the Space Shuttle launch vehicle concept bears a strong resemblance to the Navaho missile-booster combination. That is, a winged flight vehicle mounted asymmetrically on a longer boost vehicle.
Forty-two years ago this month, the Surveyor 7 spacecraft soft-landed in the lunar highlands near the Crater Tycho. It was the fifth and last Surveyor vehicle to successfully perform an autonomous landing on the Moon.
In preparation for the first manned lunar landing, the United States conducted an extensive investigation of the Moon using Ranger, Lunar Orbiter and Surveyor robotic spacecraft.
Ranger provided close-up photographs of the Moon starting at a distance of roughly 1,100 nautical miles above the lunar surface all the way to impact. Nine (9) Ranger missions were flown between 1961 and 1965. Only the last three (3) missions were successful.
Lunar Orbiter spacecraft mapped 99% of the lunar surface with a resolution of 200 feet or better. Five (5) Lunar Orbiter missions were flown between 1967 and 1968. All were successful.
Surveyor spacecraft were tasked with landing on the Moon and providing detailed photographic, geologic and environmental information about the lunar surface. Seven (7) Surveyor missions were flown between 1966 and 1968. Five (5) spacecraft successfully landed.
The Surveyor spacecraft weighed 2,300 lbs at lift-off and 674 lbs at landing. The 3-legged vehicle stood within a diameter of 15 feet and measured almost 11 feet in height. Surveyor was configured with a television camera, a surface sampler and an alpha-scattering instrument to determine the chemical composition of the lunar soil.
Surveyor 7 was launched from Kennedy Space Center’s Launch Complex 36A at 06:30:00.545 UTC on Sunday, 07 January 1968. The ride to the Moon was provided by a General Dynamics Atlas-Centaur launch vehicle. It took almost 68 hours to reach the Moon.
On Wednesday, 10 January 1968, Surveyor 7 successfully landed at 01:05:36 UTC on the lunar surface near the North Rim of Tycho Crater. A total of 20,993 photographs were taken during Surveyor 7’s first lunar day. By Friday, 26 January 1968, Surveyor 7 was powered-down for its first lunar night.
On Monday, 12 February 1968, Surveyor 7 was powered-up for its second lunar day of surface operations. The spacecraft took an additional 45 photographs and operated erratically for 9 earth-days. At 00:24 UTC on Wednesday, 21 February 1968, contact with Surveyor 7 was lost for the final time. By 06:48 UTC, the Surveyor 7 mission was officially terminated.
Although seldom remembered today, the Surveyor Program provided America with a wealth of lunar surface information critical to the Apollo Program. Surveyor’s success provided an added measure of confidence in the attainability of a manned lunar landing. Indeed, seventeen (17) months after Surveyor 7 fell silent, Astronauts Armstrong and Aldrin imprinted the lunar surface with their bootprints at Mare Tranquilitatis.
Forty-one years ago this month, three American astronauts became the first men to orbit the Earth’s Moon during the flight of Apollo 8. The flight also featured the first manned flight of the mighty Saturn V rocket booster as well as history’s first superorbital entry of a manned spacecraft.
Following the Apollo 1 tragedy in January of 1967, the United States would not fly another manned space mission until October 1968. That flight, Apollo 7, was a highly successful earth-orbital mission in which the new Block II Apollo Command Module was thoroughly flight-proven.
Notwithstanding Apollo 7 ‘s accomplishments, only 14 months remained for the United States to meet the national goal of achieving a manned lunar landing before the end of the 20th century’s 7th decade. The view held by many in late 1968 was that an already daunting task was now unachievable in the narrow window of time that remained to accomplish it.
The pessimism about reaching the Moon before the end of the decade was easy to understand. The Saturn V moon rocket had not been man-rated. The Lunar Module had not flown. Lunar Orbit Rendezvous (LOR) was untried. Men had not even so much as orbited the Moon. Yet, history would record that the United States would find a way to accomplish that which had never before been achieved.
George Low, manager of NASA’s Apollo Spacecraft Program Office, came up with the idea. Low proposed that the first manned flight of the Saturn V be a trip all the way to the Moon. It was something that Low referred to as the “All-Up Testing” concept. The newly-conceived mission would be flown in December 1968 near Christmas time.
While initially seen as too soon and too risky by many in NASA’s management hierarchy, Low’s bold proposal was ultimately accepted as the only way to meet the national lunar landing goal. Yes, there was additional risk. However, the key technologies were ready, the astronauts were willing, and the risk was tolerable.
Apollo 8 lifted-off from LC-39A at the Kennedy Space Center in Florida on Saturday, 21 December 1968 at 12:51 hours UTC. The crew consisted of NASA astronauts Frank Borman, James A. Lovell, Jr. and William A. Anders. Their target – the Moon – was 220,000 miles away.
After a 69-hour outbound journey, Apollo 8 entered lunar orbit on Tuesday, 24 December 1968 – Christmas Eve. The Apollo 8 crew photographed the lunar surface, studied the geologic features of its terrain, and made other observations from a 60-nautical mile circular orbit. The spacecraft circled the Moon 10 times in slightly over 20 hours.
The most poignant and memorable event in Apollo 8’s historic journey occurred on Christmas Eve night when each of the flight crew took turns reading from the Book of Genesis in the Holy Bible. The solemnity of the moment was evident in the voices of the astronauts. They had seen both the Moon and the Earth from a perspective that none before them had. Fittingly, they expressed humble reverence for the Creator of the Universe on the anniversary of the birth of mankind’s Redeemer.
Apollo 8 departed lunar orbit a little over 89 hours into the mission. Following a nearly 58-hour inbound trip, Apollo 8 reentered the earth’s atmosphere at 36, 221 feet per second on Friday, 27 December 1968. The first manned superorbital reentry was performed in total darkness. It was entirely successful as Apollo 8 landed less than 1 nautical mile from its target in the Pacific Ocean. The USS YORKTOWN effected recovery of the weary astronauts and their trustworthy spacecraft. Mission total elapsed time was 147 hours and 42 seconds.
The year 1968 was a tumultuous one for the United States of America. Martin Luther King and Robert Kennedy had been assassinated. American military blood flowed on the battlefields of Vietnam and civilian blood was let in countless demonstrations taking place in the nation’s cities. The ill-posed sexual revolution continued to eat away at the country’s moral moorings.
But, as is so often the case, an event from the realm of flight, now newly extended to lunar space, reminded us of our higher nature and potential. For a too brief moment, Apollo 8 put our collective purpose for being here into sharp focus. Perhaps a short phrase in a telegram sent to Frank Borman from someone he had never met said it best: “You saved 1968!”
However, looking through the lens of history, we now know that Apollo 8 did much more than end the penultimate year of the 1960’s on a positive note. Indeed, Apollo 8 saved the entire Apollo Program.
One-hundred and six years ago this month, the Wright Flyer became the first aircraft in history to achieve powered flight. The site of this historic event was Kill Devil Hills near Kitty Hawk, North Carolina.
Americans Wilbur and Orville Wright began their legendary aeronautical careers in 1899. In just four short years, the brothers would go from complete aeronautical novices to inventors and pilots of the world’s first successful powered aircraft. Interestingly, neither man attended college nor received even a high school diploma.
The Wright Flyer measured roughly 21 feet in length and had a wing span of approximately 40 feet. The biplane aircraft had an empty weight of 605 lbs. Power was provided by a single 12 horsepower, 4-cylinder engine that drove twin 8.5 foot , two-blade propellers.
The Flyer made a powered take-off run along a 60-foot wooden guide rail. The aircraft was mounted on a two-wheel dolly that rode along the track and was jettisoned at lift-off. The Flyer pilot lay prone in the middle of the lower wing. Twin elevator and rudder surfaces provided pitch and yaw control, respectively. Roll control was via differential wing warping.
The Wright Brothers had come close to achieving a successful powered flight with the Wright Flyer on Monday, 14 December 1903. Wilbur, who had won the coin toss, was the pilot for the initial attempt. However, the Flyer stalled and hit the ground sharply just after take-off. Wilbur was unhurt, but repair of the damaged aircraft would take two days.
The next attempt flight took place on Thursday, 17 December 1903. The weather was terrible. Windy and rainy. Even after the rain abated, the wind continued to blow in excess of 20 mph. The Wrights decided to fly anyway. It was now Orville’s turn as command pilot.
Orville took his position on the Flyer and was quickly launched into the wind. Once airborne, the aircraft proved difficult to control as it porpoised up and down along the flight path. Nonetheless, Orville kept the Flyer in the air for 12 seconds before landing 120 feet from the take-off point. Other than a damaged skid, the aircraft was intact and the pilot unhurt. Powered flight was a reality!
Three more flights followed on that momentous occasion as the brothers alternated piloting assignments. The fourth flight was the longest in both time aloft and distance flown. With Wilbur at the controls, the Wright Flyer flew for 59 seconds and landed 852 feet from the take-off point.
The Wright Brothers father, Milton, would soon learn of the epic events that December day in North Carolina. Orville’s verbatim Western Union telegram message sent to Dayton, Ohio read:
Success four flights thursday morning all against twenty one mile wind started from Level with engine power alone average speed through air thirty one miles longest 57 [sic] seconds inform Press home Christmas.
Fifty-six years ago this month, USAF Major Charles E. Yeager set an unofficial world speed record of 1,650 mph (Mach 2.44) in the Bell X-1A flight research aircraft. In the process, Yeager nearly lost his life.
The USAF/Bell X-1A was a second generation X-aircraft intended to explore flight beyond Mach 2. It measured 35.5 feet in length and had a wing span of 28 feet. Gross take-off weight was 16,500 pounds.
Like its XS-1 forebear, the X-1A was powered by an XLR-11 rocket motor which produced a maximum sea level thrust of 6,000 lbs. The XLR-11 burned 9,200 pounds of propellants (alcohol and liquid oxygen) in roughly 270 seconds of operation.
Departing Edwards Air Force Base, California on Saturday, 12 December 1953, Yeager and the X-1A (S/N 48-1384) were carried to altitude by a USAF B-29 mothership (S/N 45-21800 ). X-1A drop occurred at 240 knots and 30,500 feet. Within ten seconds, Yeager lit off three of the XLR-11’s four rocket chambers and started to climb upstairs.
Yeager fired the 4th chamber of the XLR-11 passing through 43,000 feet and initiated a pushover at 62,000 feet. The maneuver was completed at 76,000 feet; higher than planned. In level flight now and traveling at Mach 1.9, the X-1A continued to accelerate in the thin air of the stratosphere.
Yeager quickly exceeded Scott Crossfield’s briefly-held Mach 2.005 record set on Friday, 20 November 1953. However, he now had to be very careful. Wind tunnel testing had revealed that the X-1A would be neutrally stable in the directional channel as it approached Mach 2.3.
As Yeager cut the throttle around Mach 2.44, the X-1A started an uncommanded roll to the left. Yeager quickly countered with aileron and rudder. The X-1A then rapidly rolled right. Full aileron and opposite rudder failed to control the roll. After 8 to 10 complete revolutions, the aircraft ceased rolling, but was now inverted.
In an instant, the X-1A started rolling left and then went divergent in all three axes. The aircraft tumbled and gyrated through the sky. Control inputs had no effect. Yeager was in serious trouble. He could not control his aircraft and punching-out was not an option. The X-1A had no ejection seat.
Chuck Yeager took a tremendous physical and emotional beating for more than 70 seconds as the X-1A wildly tumbled. Normal acceleration varied between plus-8 and negative 1.3 G’s. His helmet hit the canopy and cracked it. He struck the control column so hard that it was physically bent. His frantic air-to-ground communications were distinctly those of a man who was convinced that he was about to die.
As the X-1A tumbled, it decelerated and lost altitude. At 33,000 feet, a battered and groggy Yeager found himself in an inverted spin. The aircraft suddenly fell into a normal spin from which Yeager recovered at 25,000 feet over the Tehachapi Mountains situated northwest of Edwards. Somehow, Yeager managed to get himself and the X-1A back home intact.
The culprit in Yeager’s wide ride was the then little-known phenomenon identified as roll inertial coupling. That is, inertial moments produced by gyroscopic and centripetal accelerations overwhelmed aerodynamic control moments and thus caused the aircraft to depart controlled flight. Roll rate was the critical mechanism since it coupled pitch and yaw motion.
The X-1A held the distiction of being the fastest-flying of the early X-aircraft until the Bell X-2 reached 1,900 mph (Mach 2.87) in July of 1956. Yeager’s harrowing experience in December 1953 would be his last flight at the controls of a rocket-powered X-aircraft. For his record-setting X-1A mission, he was awarded the 1953 Harmon Trophy.
Forty-six years ago this month, USAF Major Robert W. Smith zoomed the rocket-powered Lockheed NF-104A to an unofficial record altitude of 120,800 feet. This mark still stands as the highest altitude ever achieved by a United States aircraft from a runway take-off.
A zoom maneuver is one in which aircraft kinetic energy (speed) is traded for potential energy (altitude). In doing so, an aircraft can soar well beyond its maximum steady, level altitude (service ceiling). The zoom maneuver has both military and civilian flight operations value.
The USAF/Lockheed NF-104A was designed to provide spaceflight-like training experience for test pilots attending the Aerospace Research Pilot School (ARPS) at Edwards Air Force Base, California. The type was a modification of the basic F-104A aircraft. Three copies of the NF-104A were produced (S/N’s 56-0756, 56-0760 and 56-0762). It was the ultimate zoom flight platform.
In addition to a stock General Electric J79-GE-3 turbojet, the NF-104A was powered by a Rocketdyne LR121-NA-1 rocket motor. The J79 generated 15,000 pounds of thrust in afterburner and burned JP-4. The LR-121 produced 6,000 pounds of thrust and burned a combination of JP-4 and 90% hydrogen peroxide. Rocket motor burn time was on the order of 90 seconds.
The NF-104A was kinematically capable of zooming to altitudes approaching 125,000 feet. As such, it was a combined aircraft and spacecraft. The pilot had to blend aerodynamic and reaction controls in the low dynamic pressure environment near the zoom apex. He was also required to fly in a full pressure suit for survival at altitudes beyond the Armstrong Line.
On Friday, 06 December 1963, Bob Smith took-off from Edwards and headed west for the Pacific Ocean. Out over the sea, he changed heading by 180 degrees in preparation for the zoom run-in. At a point roughly 100 miles out, Smith then accelerated the NF-104A (S/N 56-0760) along a line that would take him just north of the base. Arriving at Mach 2.4 and 37,000 feet, Smith then initiated a 3.75-g pull to a 70-degree aircraft pitch angle. Turbojet and rocket were at full throttle.
Things happened very quickly now. Smith brought the turbojet out of afterburner at 65,000 feet and then moved the throttle to the idle detent at 80,000 feet. The rocket motor burned-out around 90,000 feet. Smith controlled the aircraft (now spacecraft) over the top of the zoom using 3-axis reaction controls. The NF-104A’s arcing parabolic trajectory subjected him to 73 seconds of weightlessness. Peak altitude achieved was 120,800 feet above mean sea level.
On the back side of the zoom profile, Bob Smith restarted the windmilling J79 turbojet and set-up for landing at Edwards. He touched down on the main runway and rolled out uneventfully. Total mission time from brake-release to wheels-stop was approximately 25 minutes.
Much more could be said about the NF-104A and its unique mission. Suffice it to say here that two of the aircraft ultimately went on to serve in the ARPS from 1968 to 1971. The only remaining aircraft today is 56-0760 which sits on a pole in front of the USAF Test Pilot School at Edwards.
Bob Smith went on to make many other noteworthy contributions to aviation and his nation. Having flown the F-86 Sabre in Korea, he volunteered to fly combat in Viet Nam in his 40th year. Stationed at Korat AFB in Thailand, he commanded the 34th Fighter Squadron of the 388th Tactical Fighter Wing. Smith flew 100 combat missions in the F-105; many of which involved the infamous Pack VI route in North Viet Nam.
Bob Smith is a true American hero. Like so many of the airmen of his day, Smith is a man whose dedication, service, and courage went largely unnoticed and unappreciated by his fellow countrymen. However, for those who know the true character and heart of Bob Smith and those of his ilk, we offer this sincere, but clearly inadequate sentiment: Thank You.
Eighty years ago this month, a four-man crew became the first Antarctic explorers to fly over the Earth’s South Pole. The aircraft used to make the historic flight was a Ford Trimotor.
While substantial exploration of the Artic and Antarctic by land and sea had occurred far earlier, exploration of these regions by air was in its infancy during the decade of the 1920’s. Of particular focus was the goal to fly over both the North and South Poles.
The historic first flight to the South Pole originated from Little America, an exploration base camp situated on Antartica’s Ross Ice Shelf. Distance to the South Pole was about 800 miles as the crow flies.
A Ford Trimotor aircraft, the Floyd Bennett (S/N NX4542), was selected for the epic polar air journey. The crew consisted of pilot Bernt Balchen, co-pilot Harold June, navigator Richard E. Byrd, and radio operator Ashley McKinley.
The fabled Trimotor was well-suited for the rigors of polar flight. The all-metal aircraft measured 50-feet in length and had a wing span of 76-feet. Empty weight was roughly 6,500 pounds. Power was provided by a single 520-HP Wright Cylone and a pair of 200-HP Wright Whirlwind radial engines.
Following departure from Little America at 02:39 UTC, the Floyd Bennett headed for the South Pole. Navigation was via sun compass due to the proximity of the South Magnetic Pole.
Myriad glaciers, massifs, plateaus, and crevasses marked the stark, rugged landscape unfolding under the Floyd Bennett’s flight path. The most imposing of these geological features were the Queen Maud Mountains that towered more than 11,000 feet above sea level.
Pilot Balchen struggled to get his aircraft over the high mountain pass that runs between Mounts Fridtjof and Fisher. The crew jettisoned empty fuel cans and hundreds of pounds of precious food to lighten the load. The Floyd Bennett cleared the terrain by about 600 feet.
Just after 1200 UTC (local midnight) on Friday, 29 November 1929, the Floyd Bennett and its crew flew over the Earth’s South Pole. After briefly loitering around the Pole, the aircraft headed back to Little America at 1225 UTC.
According to plan, Balchen landed the airplane to take on 200 gallons of fuel that had been pre-positioned at the base of the Liv Glacier. The Floyd Bennett took-off again and landed back at Little America around 21:10 UTC. Total mission time was nearly 19 hours.
United States Navy Commander Richard E. Byrd now had flown over both poles. He would go on to successfully explore the Antarctic for many more years. For his part in the South Pole overflight, Byrd was promoted to the rank of Rear Admiral.
Today, the aircraft that made the first flight over the South Pole in November 1929 is displayed in the Heroes of the Sky exhibit at the Henry Ford Museum in Dearborn, Michigan.
Forty-eight years ago this month, a United States Navy YF4H-1 Phantom II set a world absolute speed record of 1,606.342 mph. Piloting the record flight was United States Marine Corps Lieutenant Colonel Robert B. Robinson.
The McDonnell Douglas YF4H-1 Phantom II was first flown in May 1958. The aircraft measured 58 feet length with a wing span of 38 feet. Gross take-off weight was 44,000 pounds. A pair of General Electric J79-GE-8 turbojets produced a total of 34,000 pounds of thrust in afterburner.
The YF4H-1 was the first in a long line of Phantom II variants that would eventually see a production run of 5,195 aircraft. Second only to the nearly 10,000 production units of the multi-variant North American F-86 Sabre.
Since 1961 marked the 50th anniversary of Naval Aviation, the US Navy planned to celebrate by establishing a series of speed records. The aircraft of choice was their super-powered Phantom II. Operation SAGEBURNER was the low altitude speed program (i.e., 125 feet off the deck) while Operation SKYBURNER was the high altitude speed component.
On Wednesday, 22 November 1961, the second YF4H-1 (S/N 142260) took-off from Edwards Air Force Base, California in an attempt to surpass the existing world absolute speed record. A United States Air Force F-106 Delta Dart, piloted by Major Joseph W. Rogers, held the existing record of 1,525.96 mph which was set on Tuesday, 15 December 1959.
Robinson had to fly a precisely-timed and positioned flight profile to extract maximum performance from his YF4H-1. FAI rules required the aircraft to enter the Edwards speed course in level flight and to make two runs. The final speed mark would be the average of the two runs.
The Phantom II was a big airplane and had to carry a lot of fuel. In addition to a full internal fuel load, the aircraft carried a 600-gallon centerline tank and a pair of 370-gallon wing tanks. Following take-off to the east, climb-out was made to the south toward El Centro, California. Arriving in the area, Robinson made a sweeping left-hand turn over the Salton Sea and accelerated the aircraft north back towards Edwards.
As the aircraft gained speed, Robinson dropped the empty centerline fuel tank over the Chocolate Mountains gunnery range. Then, arriving over the Bristol Dry Lake range, he punched-off the empty wing tanks. The aircraft was now lighter and aerodynamically cleaner.
Robinson approached the Edwards speed course from the east in full afterburner. The Phantom II exited the 20-mile course quickly. Following his first pass, Robinson came out of afterburner, made a Mach 0.9 turn to the south, cruised 105 miles out and then made the turn back to Edwards for the second speed pass.
His aircraft lighter now and not having to concern himself with the logistics of dropping empty fuel tanks, Robinson was clocked at over 1,700 mph on his second time through the Edwards speed course. The two-run average was 1,606.342 mph; a new world absolute speed record.
The F-4 Phantom II would go on to a lengendary combat career in both the United States Navy and United States Air Force. Among many distinctions, the McDonnel Douglas F-4 Phantom II is the only aircraft to have seen service with both the USAF Thunderbirds (1969-1973) and the USN Navy Blue Angels (1969-1974) flight demonstration squadrons.
For setting the world absolute speed record in 1961, Operation SKYBURNER pilot Bob Robinson was presented with the Distinguished Flying Cross by the then-Secretary of the Navy, John B. Connally.
Five years ago today, the NASA X-43A scramjet-powered flight research vehicle reached a record speed of over 6,600 mph (Mach 9.68). In doing so, the X-43A broke its own record speed of Mach 6.83 (4,600 mph) and became the fastest airbreathing aircraft of all time.
In 1996, NASA initiated a technology demonstration program known as HYPER-X. The central goal of the HYPER-X Program was to successfully demonstrate sustained supersonic combustion and thrust production of a flight-scale scramjet propulsion system at speeds up to Mach 10.
Also known as the HYPER-X Research Vehicle (HXRV), the X-43A aircraft was a scramjet test bed. The aircraft measured 12 feet in length, 5 feet in width, and weighed close to 3,000 pounds. The X-43A was boosted to scramjet take-over speeds with a modified Orbital Sciences Pegasus rocket booster.
The combined HXRV-Pegasus stack was referred to as the HYPER-X Launch Vehicle (HXLV). Measuring approximately 50 feet in length, the HXLV weighed slightly more than 41,000 pounds. The HXLV was air-launched from a B-52 mothership. Together, the entire assemblage constituted a 3-stage vehicle.
The third and final flight of the HYPER-X program took place on Tuesday, 16 November 2004. The flight originated from Edwards Air Force Base, California. Using Runway 04, NASA’s venerable B-52B (S/N 52-0008) started its take-off roll at approximately 21:08 UTC. The aircraft then headed for the Pacific Ocean launch point located just west of San Nicholas Island.
At 22:34:43 UTC, the HXLV fell away from the B-52B mothership. Following a 5 second free fall, rocket motor ignition occurred and the HXLV initiated a pull-up to start its climb and acceleration to the test window. It took the HXLV 75 seconds to reach a speed of slightly over Mach 10.
Following rocket motor burnout and a brief coast period, the HXRV (X-43A) successfully separated from the Pegasus booster at 109,440 feet and Mach 9.74. The HXRV scramjet was operative by Mach 9.68. Supersonic combustion and thrust production were successfully achieved. Total engine-on duration was approximately 11 seconds.
As the X-43A decelerated along its post-burn descent flight path, the aircraft performed a series of data gathering flight maneuvers. A vast quantity of high-quality aerodynamic and flight control system data were acquired for Mach numbers ranging from hypersonic to transonic. Finally, the X-43A impacted the Pacific Ocean at a point about 850 nautical miles due west of its launch location. Total flight time was approximately 15 minutes.
The HYPER-X Program was now history. Supersonic combustion and thrust production of an airframe-integrated scramjet had indeed been achieved for the first time in flight; a goal that dated back to before the X-15 Program. Along the way, the X-43A established a speed record for airbreathing aircraft and earned several Guinness World Records for its efforts.
As a footnote to the X-43A story, the HYPER-X Flight 3 mission would also be the last for NASA’s fabled B-52B mothership. The aircraft that launched many of the historic X-15, M2-F2, M2-F3, X- 24A, X-24B and HL-10 flight research missions, and all three HYPER-X flights, would take to the air no more. In tribute, B-52B (S/N 52-0008) now occupies a place of honor at a point near the North Gate of Edwards Air Force Base.
Forty-three years ago this month, NASA’s pioneering spaceflight program, Project Gemini, was brought to a successful conclusion with the 4-day flight of Gemini XII. Remarkably, the mission was the tenth Gemini flight in 20 months.
Boosted to Earth orbit by a two-stage Titan II launch vehicle, Gemini XII Command Pilot James A. Lovell, Jr. and Pilot Edwin E. “Buzz” Aldrin, Jr. lifted-off from Cape Canaveral’s LC-19 at 20:46:33 UTC on Friday, 11 November 1966. The flight was Lovell’s second trip into space and Aldrin’s first.
Like almost every Gemini mission before it, Gemini XII was not a glitch-free spaceflight. For instance, when the spacecraft’s rendezvous radar began acting oddly, the crew had to resort to sextant and chart to complete the last 65 nautical miles of the rendezvous with their Agena Target Vehicle. But, overcoming this and other obstacles served to provide the experience and instill the confidence needed to meet the truly daunting challenge that lay ahead; landing on the Moon.
Unquestionably, Gemini XII’s single most important contribution to the United States manned space effort was validating the notion that a well-trained astronaut could indeed do useful work in an Extra-Vehicular Activity (EVA) environment. The exhausting and even dangerous EVA experiences of Gene Cernan on Gemini IX and Dick Gordon on Gemini XI brought into sharp focus the challenge of performing even seemingly simple work assignments outside the Gemini spacecraft.
Buzz Aldrin performed a trio of EVA’s on Gemini XII. Two of these involved standing in his seat with the hatch open. The third involved a tethered EVA or space walk. On the latter, Aldrin successfully moved about the exterior of the Gemini-Agena combination without exhausting himself. He also used a special-purpose torque wrench to perform a number of important work tasks. Central to Aldrin’s success was the use of foot restraints and auxiliary tethers to anchor his body while floating in a weightless state.
Where others had struggled and not been able to accomplish mission EVA goals, Buzz Aldrin came off conqueror. One of the chief reasons for his success was effective pre-flight training. A pivotal aspect of this training was to practice EVA tasks underwater as a unique means of simulating the effects of weightlessness. This approach was found to be so useful that it has been used ever since to train American EVA astronauts.
Lovell and Aldrin did many more things during their highly-compressed 4-day spaceflight in November of 1966. Multiple dockings with the Agena, Gemini spacecraft maneuvering, tethered stationkeeping exercises, fourteen scientific experiments, and photographing a total eclipse occupied their time aloft.
On Tuesday, 15 November 1966, on their 59th orbit, a tired, but triumphant Gemini XII crew returned to Earth. The associated reentry flight profile was automated; that is, totally controlled by computer. Yet another first and vital accomplishment for Project Gemini. Splashdown was in the West Atlantic at 19:21:04 UTC.
While Gemini would fly no more, both Lovell and Aldrin certainly would. In fact, both men would play prominent roles in several historic flights to the Moon. Jim Lovell flew on Apollo 8 in December 1968 and Apollo 13 in April 1970. And of course, Buzz Aldrin would walk on the Moon at Mare Tranquilitatis in July 1969 as the Lunar Module Pilot for Apollo 11.
Fifty-six years ago this month, the USN/Douglas D-558-II Skyrocket became the first aircraft to fly at twice the speed of sound. This historic event took place on Friday, 20 November 1953 at Edwards Air Force Base, California.
The D-558-II was a United States Navy (USN) X-aircraft and first flew in February of 1948. It was contemporaneous with the USAF/Bell XS-1. The aircraft measured 42 feet in length with a wing span of 25 feet. Maximum take-off weight was 15,266 pounds. Douglas manufactured a trio of D-558-II aircraft (Bureau No.’s 37973, 37974 and 37975).
The original version of the swept-wing D-558-II had both rocket and turbojet propulsion. The latter system providing a ground take-off capability. However, like other early X-aircraft such as the XS-1, X-1A, X-2 and X-15), the D-558-II achieved max performance through the use of a mothership and rocket power alone.
On that record-setting day in November 1953, the D-558-II (Bureau No. 37974) was carried to the drop altitude of 32,000 feet by a USN P2B-1S (Bureau No. 84029). NACA test pilot A. Scott Crossfield was in the D-558-II cockpit. Although ailing with the flu, Crossfield was not about to let a little urpiness force him to miss today’s events!
Following drop, Crossfield ignited the Reaction Motors LR8-RM-6 (USN designation for the XLR-11) rocket motor and started uphill. After closely adhering to a carefully planned climb schedule, Crossfield initiated a pushover at 72,000 feet that resulted in a shallow dive. Passing through 62,000 feet, the D-558-II hit 1,291 mph; Mach 2.005.
The D-558-II reached Mach 2 due to a confluence of several factors. First, Crossfield flew the profile as briefed. Second, temperatures at altitude that day were unusually low. This lowered the speed of sound and thus increased Mach number. Third, the ground crew did an extraordinary job of optimizing the D-558-II for the max speed mission.
Expanding on the last point mentioned above, extension tubes were added to the LR8-RM-6 rocket motor. This increased thrust from 6,000 to 9,000 pounds. The aircraft was then cold-soaked overnight in an effort to maximize its propellant load. Finally, external airframe gaps and panel openings were taped over and the aircraft was waxed and polished in an effort to minimize aerodynamic drag.
Scott Crossfield received the 1954 Lawrence B. Sperry Award for his Mach 2 exploits. The record-setting aircraft (Bureau No. 37934) is currently displayed at the National Air and Space Museum in Washington, D.C. in tribute to its many contributions to aviation history.
Fifty-five years ago this month, the USAF/Douglas X-3 Stiletto research aircraft exhibited a then little known dynamic instability mode during a flight test with NACA test pilot Joseph A. Walker at the controls.
The X-3 was designed to fly at speeds up to Mach 2. The aircraft was approximately 67 feet in length and had a wing span on the order of 23 feet. Gross weight was 23,840 pounds.
A pair of Westinghouse J46-WE-1 turbojets were intended to power the X-3. However, protracted developmental problems and installation issues with these powerplants would eventually prevent their use in the aircraft.
The X-3 was ultimately outfitted with a pair of Westinghouse J34-WE-17 turbojets. The result was that the X-3 was now underpowered and could barely fly supersonically. Maximum achieved Mach number was 1.21 and that was in a 30-deg dive!
Notwithstanding the above, the X-3 took to the air 54 times between October 1952 and May 1956 for the purpose of conducting transonic flight research. It would be on its 43rd flight that the X-3 would make its most important contribution to aviation.
On Wednesday, 27 October 1954, Joe Walker took-off in the X-3 (S/N 49-2892) from Edwards Air Force Base, California. At Mach 0.92 and 30,000 feet, Walker applied left aileron at fixed-rudder in an effort to develop a rapid roll response. To Walker’s utter amazement, the X-3 went wild in both pitch and yaw.
Although it seemed to last much longer, Walker was able to recover control of the X-3 within 5 seconds of his initial left aileron input. In true test pilot fashion, Walker again made an abrupt rudder-fixed left aileron input at Mach 1.05. The same thing happened. However, this time the aircraft’s motions were more violent.
Happily, Walker again recovered control of the X-3. Having had enough of flight test frontiersmanship for one day, Walker uneventfully recovered the aircraft to Edwards.
The phenomenon that Joe Walker and the X-3 encountered that day in 1954 is known as Inertial Roll Coupling. It is a resonant divergence in either pitch or yaw due to the presence of roll rate. Aircraft like the X-3, which have low longitudinal and/or directional static stability as well as high pitch-to-roll and yaw-to-roll moment of inertia ratios, are especially susceptible to this phenomenon.
As a postscript to our story, the phenomenon of Inertial Roll Coupling had been hypothesized by the NACA’s William H. Phillips back in June of 1948. For Joe Walker in October of 1954, engineering theory would become flight test fact in a few terrifying seconds high in the skies over Edwards Air Force Base.
Forty-one years ago this month, NASA successfully conducted the first manned Apollo Earth-orbital mission with the flight of Apollo 7. This mission was a critically-important milestone along the path to the first manned lunar landing in July 1969.
The launch of Apollo 7 took place from Launch Complex 34 at Cape Canaveral Air Force Station, Florida at 15:02:45 UTC on Friday, 11 October 1968. The flight crew consisted of NASA astronauts Walter M. Schirra, Donn F. Eisele, and R. Walter Cunningham. Their primary goal was to thoroughly qualify the new Apollo Block II Command Module (CM) during 11 days in space.
Apollo 7 was not only the first flight of the Block II CM, but in fact the first manned mission in the Apollo Program. Apollo 7 also featured the first use of the Saturn IB launch vehicle in a manned mission. Apollo 7’s critical nature stemmed from the tragic Apollo 1 fire that took the lives of Virgil I. (Gus) Grissom, Edward H. White II, and Roger B. Chaffee on Friday, 27 January 1967.
The Apollo 1 fire was attributed to numerous deficiencies in the design, construction, and testing of its Block I CM. The Block II spacecraft flown on Apollo 7 was a major redesign of the Apollo Command Module and was in every sense superior to the Block I vehicle. However, it had taken 21 months to return to flight status and the Nation’s goal of a manned lunar landing within the decade of the 1960’s was in serious jeopardy.
The Apollo 7 crew orbited the Earth 163 times at an orbital altitude that varied between 125 and 160 nautical miles. In that time, they rigorously tested every aspect of their Block II CM. This testing included 8 firings of the Service Propulsion System (SPS) while in orbit. Apollo 7 splashdown occurred in the Atlantic Ocean near the Bermuda Islands at 11:11:48 UTC on Tuesday, 22 October 1968.
The Nation’s Lunar Landing Program overwhelmingly got the unqualified success that it desperately needed from the Apollo 7 mission. The Apollo Block II CM would provide yeoman service throughout the time of Apollo. The spacecraft would also go on to see service in the Skylab and Apollo-Soyuz Test Project programs.
While the technical performance of the Apollo 7 crew was unquestionably superb, their interaction with Mission Control at Johnson Spacecraft Center (JSC) in Houston, Texas was quite strained. The crew suffered from head colds through much of the mission and the food quality was poor. Coupled with Houston’s incessant attempts to cramp more tasks into each moment of the mission, Apollo 7 Commander Schirra took control of his ship and made the ultimate decisions as to what work would be performed onboard the spacecraft.
The flight of Apollo 7 would be Wally Schirra’s last mission in space as he had announced prior to flight. Schirra holds the distinction of being the only astronaut to have flown Mercury, Gemini, and Apollo missions.
Interestingly, Apollo 7 was not only Schirra’s last time in space, but it was Donn Eisele’s and Walt Cunningham’s first and last space mission as well. That there is a direct connection between this historical fact and the crew’s insubordinative behavior during Apollo 7 is obvious to the inquiring mind.
Sixty-two years ago this month, the legendary USAF/Bell XS-1 experimental aircraft exceeded the speed of sound when it reached a maximum speed of 700 mph (Mach 1.06) at 45,000 feet.
Bell Aircraft Corporation of Buffalo, New York built three copies of the XS-1 under contract to the United States Army Air Forces (USAAF). The aircraft were designed to approach and then fly beyond the speed of sound.
The Bell XS-1 was 31-feet in length and had a wing span of 28 feet. Gross take-off weight was around 12,500 lbs. The aircraft had an empty weight of about 7,000 lbs. Propulsion was provided by a Reaction Motors XLR-11 rocket motor capable of generating a maximum thrust of 6,000 lbs.
On the morning of Tuesday, 14 October 1947, the XS-1 (S/N 46-062) dropped away from its B-29 mothership (S/N 45-21800 ) as the pair flew at 220 mph and 20,000 feet. In the XS-1 cockpit was USAAF Captain and World War II ace Charles E. Yeager. The young test pilot had named the aircraft Glamorous Glennis in honor of his wife.
Following drop, Yeager sequentially-lit all four XLR-11 rocket chambers during a climb and push-over that ultimately brought him to level flight around 45,000 feet. The resulting acceleration profile propelled the XS-1 slightly beyond Mach 1 for about 20 seconds. Yeager then shutdown the rocket, decelerated to subsonic speeds, and landed the XS-1 on Muroc Dry Lake at Muroc Army Airfield, California.
The world would not find out about the daring exploits of 14 October 1947 until December of the same year. As it was, the announcement came from a trade magazine that even today is sometimes referred to as “Aviation Leak”.
Today, Glamorous Glennis is prominently displayed in the Milestones of Flight hall of the National Air and Space Museum located in Washington, DC. For his efforts in breaking the sound barrier, Chuck Yeager was a co-recipient of the 1948 Collier Trophy.
Forty-two years ago this month, USAF Major William J. “Pete” Knight piloted the fabled USAF/North American X-15A-2 hypersonic research aircraft to a record speed of 4,520 mph – about a mile and a quarter per second.
North American’s original X-15 production run consisted of three (3) aircraft. The X-15A-2 was a rebuild of the 2nd airframe (S/N 56-6671) which had been severely damaged during an emergency landing at Mud Lake, Nevada in November of 1962.
The rebuilt aircraft was configured with a pair of droppable propellant tanks that allowed the type’s XLR-99 rocket engine to operate 60 seconds beyond the stock X-15’s 80-second burn time. Among other modifications, the aircraft also carried a pylon-mounted dummy ramjet in the ventral region of the aft fuselage.
With the addition of the external propellant tanks, the X-15A-2 was really a three-stage vehicle. The first stage was the NASA NB-52B mothership which launched the X-15 at Mach 0.82 and 45,000 feet. The second stage consisted of the propellant-laden external tanks which were jettisoned at Mach 2.0 and 70,000 feet. The third stage was the X-15A-2 with its entire internal propellant load.
Due to the increased speed of the X-15A-2, the aircraft was covered with Martin MA-25S ablator to protect it from the higher aerodynamic heating loads. The baseline ablator was pink in color and gave the X-15A-2 a rather odd appearance. Fortunately, application of a white wear/sealer over the ablator gave the aircraft a more dignified look.
On Tuesday, 03 October 1967, Pete Knight and the X-15A-2 dropped away from the NB-52B (S/N 52-008) at the start of the X-15 Program’s 188th mission. Knight ignited the XLR-99 rocket engine and excuted a pull-up followed by a pushover to level flight at a little over 102,000 feet. Aircraft speed at XLR-99 burnout was 4,520 mph (Mach 6.7).
As the aircraft decelerated following burnout, Knight executed a series of pre-planned flight maneuvers to acquire vital aerodynamics data. However, passing through Mach 5.5, he received an indication in the cockpit that a high temperature condition existed in the XLR-99 engine bay.
Knight attempted to jettison the aircraft’s remaining propellants, but to no avail. The jettison tubes were welded shut by whatever was happening in the engine bay. This meant he would land heavier and faster than usual. Fortunately, Knight’s piloting skills allowed him to get the X-15A-2 on to Rogers Dry Lake in one piece.
As flight support personnel inspected the X-15A-2 airframe following Knight’s emergency landing, they were alarmed at what they found. The aft ventral region of the aircraft had incurred significant thermal damage. Further, the dummy ramjet was gone.
As reported in the classic NASA document, TM-X-1669, higher-than-expected aerodynamic heating levels were responsible for the damage to the X-15A-2.
First, shock wave/boundary layer interaction heating on the lower fuselage just ahead of the pylon (1) completely destroyed the ablator in that region and (2) penetrated the Inconel-X airframe structure. This introduced very high temperature air into the X-15 engine bay.
Second, impingement of the dummy ramjet nose shock on the detached bow shock coming off of the pylon produced a shear layer that focused on the pylon leading edge. The resulting heating rates were of sufficient magnitude and duration to both burn away the pylon ablator and burn through the pylon structure. The weakened pylon attachment eventually failed and the dummy ramjet departed the main airframe.
Pete Knight will forever hold the record for the fastest X-15 flight. However, the X-15A-2 never flew again. Only 11 more flights remained in the X-15 Program at the time. A lack of time and funding meant that little was to be gained by repairing the thermally-damaged aircraft.
As for the final disposition of the X-15A-2 (S/N 56-6671), the aircraft’s remaining ablator was removed with its external surface cleaned-up and original markings restored. The aircraft now resides in a place of honor at the National Museum of the United States Air Force located at Wright-Patterson AFB in Dayton, Ohio.
Fifty-three years ago this month, the Bell X-2 rocket-powered research aircraft reached a record speed of 2,094 mph with USAF Captain Milburn G. “Mel” Apt at the controls. This corresponded to a Mach number of 3.2 at 65,000 feet.
Mel Apt’s historic achievement came about because of the Air Force’s desire to have the X-2 reach Mach 3 before turning it over to the National Advisory Committee For Aeronautics (NACA) for further flight research testing. Just 20 days prior to Apt’s flight in the X-2, USAF Captain Iven C. Kincheloe, Jr. had flown the aircraft to a record altitude of 126,200 feet.
On Thursday, 27 September 1956, Apt and the last X-2 aircraft (S/N 46-674) dropped away from the USAF B-50 motherhip at 30,000 feet and 225 mph. Despite the fact that Apt had never flown an X-aircraft, he executed the flight profile exactly as briefed. In addition, the X-2’s twin-chamber XLR-25 rocket motor burned propellant 12.5 seconds longer than planned. Both of these factors contributed to the aircraft attaining a speed in excess of 2,000 mph.
Based on previous flight tests as well as flight simulator sessions, Apt knew that the X-2 had to slow to roughly Mach 2.4 before turning the aircraft back to Edwards. This was due to degraded directional stability, control reversal, and aerodynamic coupling issues that adversely affected the X-2 at higher Mach numbers.
However, Mel Apt was now faced with a difficult decision. If he waited for the X-2 to slow to Mach 2.4 before initiating a turn back to Edwards Air Force Base, he quite likely would not have enough energy and therefore range to reach Rogers Dry Lake. On the other hand, if he decided to initiate the turn back to Edwards at high Mach number, he risked having the X-2 depart controlled flight. Apt opted for the latter.
As Apt increased the aircraft’s angle-of-attack, the X-2 careened out of control and subjected him to a brutal pounding. Aircraft lateral acceleration varied between +6 and -6 g’s. The battered pilot ultimately found himself in a subsonic, inverted spin at 40,000 feet. At this point, Apt effected pyrotechnic separation of the X-2’s forebody which contained the cockpit and a drogue parachute.
X-2 forebody separation was clean and the drogue parachute deployed properly. However, Apt still needed to bail out of the X-2’s forebody and deploy his personal parachute to complete the emergency egress process. But, it was not to be. Mel Apt ran out of time, altitude, and luck. He lost his life when the X-2 forebody that he was trying to escape from impacted the ground at several hundred miles an hour.
Mel Apt’s flight to Mach 3.2 established a record that stood until the X-15 exceeded it in August 1960. However, the price for doing so was very high. The USAF lost a brave test pilot and the lone remaining X-2 on that fateful day in September 1956. The mishap also ended the USAF X-2 Program. NACA never did conduct flight research with the X-2.
However, for a few terrifying moments, Mel Apt was the fastest man alive.
Fifty-two years ago this month, the United States successfully tested a USAF/Douglas Thor missile for the first time. Thor Vehicle 105, launched from Launch Complex 17 at Cape Canaveral, flew 1,100 miles down the Eastern Test Range (ETR) on Saturday, 21 September 1957.
Named after the Norse god of thunder, the Thor (PGM-17A) was designed as a nuclear-armed Intermediate Range Ballistic Missle (IRBM). Operational Thor missiles were armed with a single W49 nuclear warhead having an explosive yield equivalent to 1.44 megatons of TNT.
The Thor measured 65 feet in length and had a maximum diameter of 8 feet. Weighing 110,000 pounds at lift-off, the test vehicle climbed-out on 150,000 pounds of thrust generated by its single Rocketdyne LR79-NA-9 first stage rocket motor. The powerplant used LOX/Kerosene propellants and had a nominal burn time of 165 seconds. Specific impulse was around 280 seconds.
Following development flight testing, the Thor would become the first operational ballistic missile deployed by the United States. Sixty Thor missiles were tended by twenty RAF missile squadrons scattered throughout the United Kingdom from 1958 through 1963.
Although its tour of duty was brief, the Thor served as an effective deterent to Soviet agression until the arrival of the first true Intercontinental Ballistic Missiles (ICBM). Interestingly, the Thor IRBM would become the basis for the first Delta launch vehicles, descendants of which remain in active service up to the current day.
Thirty-five years ago this month, the legendary USAF/Lockheed SR-71A Blackbird triple-sonic aircraft established an official world speed record as it traversed the 5,446.87 statute miles between London and Los Angeles in 3 hours 47 minutes and 39 seconds. Average speed was 1,435.59 mph.
The all-USAF crew of Captain Harold B. Adams (Pilot) and Major William C. Machorek (RSO) flew the historic mission in aircraft S/N 61-17972 on Friday, 13 September 1974. In their rapid east-to-west journey, the record-setting aircraft and its crew crossed 7 separate time zones.
To gain an added appreciation for the Blackbird’s impressive performance, one might consider the following. The Earth rotates through an arc distance of a little over 1,000 miles in one hour. The Blackbird averaged over 1,400 miles arc distance in one hour. In that sense, the aircraft out-raced the sun as it flew more than one-fifth the total distance around the globe.
Fittingly, the crew of Adams and Machorek received the FAI’s prestigous De La Vaulx medal in honor of their London-to-Los Angeles world speed record which stands to this very day.
Fifty-three years ago today, the USAF/Bell X-2 research aircraft flew to an altitude of 126,200 feet. This accomplishment took place on the penultimate mission of the type’s 20-flight aeronautical research program. The date was Friday, 07 September 1956.
The X-2 was the successor to Bell’s X-1A rocket-powered aircraft which had recorded maximum speed and altitude marks of 1,650 mph (Mach 2.44) and 90,440 feet, respectively. The X-2 was designed to fly beyond Mach 3 and above 100,000 feet. The X-2’s primary mission was to investigate aircraft flight control and aerodynamic heating in the triple-sonic flight regime.
The X-2 had a gross take-off weight of 24,910 lbs and was powered by a Curtis-Wright XLR-25 rocket motor which generated 15,000-lbs of thrust. Aircraft empty weight was 12,375 lbs. Like the majority of X-aircraft, the X-2 was air-launched from a mothership. In the X-2’s case, an USAF EB-50D served as the drop aircraft. The X-2 was released from the launch aircraft at 225 mph and 30,000 feet.
The pilot for the X-2 maximum altitude mission was USAF Captain Iven Carl Kincheloe, Jr. Kicheloe was a Korean War veteran and highly accomplished test pilot. He wore a partial pressure suit for survival at extreme altitude.
While the dynamic pressure at the apex of his trajectory was only 19 psf, Kincheloe successfully piloted the X-2 with aerodynamic controls only. The X-2 did not have reaction controls. Mach number over the top was supersonic (approximately Mach 1.7).
Kicheloe’s maximum altitude flight in the X-2 (S/N 46-674) would remain the highest altitude achieved by a manned aircraft until August of 1960 when the fabled X-15 would fly just beyond 136,000 feet. However, for his achievement on this late summer day in 1956, the popular press would refer to Iven Kicheloe as the “First of the Space Men”.
We take pause this week from our regular aerospace retrospective and consider a topic of a different nature. Such a change-of-pace seems quite natural as summer wanes and legions of new and returning education seekers troop through the portals of our country’s universities. However, rather than focus on the matriculating crowd, we will set our sights on those who have completed their formal education and are now members of the American aerospace workforce.
Education does not end with the granting of a diploma or even a collection of diplomas. This is especially the case in today’s aerospace industry which encompasses so many disciplines and technical specialties. And the list grows as new technology emerges. For the successful aerospace engineer, learning and gaining technical knowledge is truly a daunting career-long process.
The majority of one’s technical skills, critical knowledge, and lessons-learned are acquired on the job. However, professional short courses also serve a vital role in one’s career development. A well designed and capably taught aerospace professional short course provides the engineer with critical specialty knowledge and disciplinary technical context in a very short amount of time. And it does so at low cost.
Aerospace professional short courses are most typically taught by subject matter experts (SME’s) who have successfully plied their trade over a career that often spans decades. These SME’s know their specialty area intimately by virtue of this vast experience. Further, they are often passionate about and notable contributors to their technical discipline.
Somewhat fortuitously, the majority of SME’s who teach aerospace professional short courses are often very good technical instructors. They understand what the learner needs to know and how to convey that knowledge. A capable aerospace professional short course instructor also has an uncanny ability to inspire his or her audience to learn and grow. That kind of instruction is infectious and makes it a true pleasure to learn.
While there is certainly more to say concerning the merits of the aerospace professional short course, it seems appropriate to end this session with the following observation. Among the most valuable aspects of the aerospace professional short course are (1) the review and understanding of key aerospace historical events and (2) the transmittal of hard-won engineering lessons-learned.
In the fast-paced, competitive, high-stakes and cost-conscious aerospace market of the 21st century, the victory will most often go to those who learn from and clearly remember the experiences of the past.
Forty-six years ago this month, NASA chief research pilot Joseph A. Walker flew X-15 Ship No. 3 (S/N 56-6672) to an altitude of 354,200 feet. This flight would mark the highest altitude ever achieved by the famed hypersonic research vehicle. The date was Thursday, 22 August 1963.
Carried aloft by NASA’s NB-52A (S/N 52-0003) mothership, Walker’s X-15 was launched over Smith Ranch Dry Lake, Nevada at 17:05:42 UTC. Following drop at around 45,000 feet and Mach 0.82, Walker ignited the X-15’s small, but mighty XLR-99 rocket engine and pulled into a steep vertical climb.
The XLR-99 was run at 100 percent power for 85.8 seconds with burnout occurring around 176,000 feet on the way uphill. Maximum velocity achieved was 3,794 miles per hour which tranlates to Mach 5.58 at the burnout altitude. Following burnout, Walker’s X-15 gained an additional 178,200 feet in altitude as it coasted to apogee.
Joe Walker went over the top at 354,200 feet (67 miles). Although he didn’t have much time for sight-seeing, the Earth’s curvature was strikingly obvious to the pilot as he started downhill from his lofty perch. Walker subsequently endured a hefty 5-g’s of eyeballs-in normal acceleration during the backside dive pull-out. The aircraft was brought to a wings-level attitude at 70,000 feet. Shortly after, Walker greased the landing on Rogers Dry Lake at Edwards Air Force Base, California.
The X-15 maximum altitude flight lasted 11 minutes and 8 seconds from drop to nose wheel stop. In that time, Walker and X-15 Ship 3 covered 305 miles in ground range. The mission was Ship No. 3’s 22nd flight and the 91st of the X-15 Program.
For Joseph Albert Walker, the 22nd of August 1963 marked his 25th and last flight in an X-15 cockpit. The mission qualified him for Astronaut Wings since he had exceeded the 328,000 foot (100 km) FAI/NASA standard set for such a distinction. Ironically, the historic record indicates that Joe Walker never officially received Astronaut Wings for this flight in which the X-15 design altitude was exceeded by over 100,000 feet.
Forty-nine years ago this month, USAF Captain Joseph W. Kittinger, Jr. successfully completed a daring parachute jump from 102,800 feet (19.5 miles). The historic bailout took place on Tuesday, 16 August 1960 over the Tularosa Basin of New Mexico.
Kittinger’s jump was the final mission of the three-jump Project Excelsior flight research effort which focused on manned testing of the Beaupre Multi-Stage Parachute Parachute (BMSP). The system was being developed to provide USAF pilots with a means of survival from an extreme altitude ejection.
Transport to jump altitude was via a 3-million cubic foot helium balloon. Kittinger rode in an open gondola. He was protected from the harsh environment by an MC-3 partial pressure suit as well as an assortment of heavy cold-weather clothing. Kittinger and his jump wardrobe and flight gear weighed a total of 313 pounds
The Excelsior III mission was launched just north of Alamogordo, New Mexico at 11:29 UTC. Ninety-three minutes later, Kittinger’s fragile balloon reached float altitude. At 13:12 UTC, Kittinger stepped out of the gondola and into space. As he did so, he said: “Lord, take care of me now!”
The historic record shows that Joe Kittinger experienced a free-fall that lasted 4 minutes and 36 seconds. During this time, he fell 85,300 feet (16.2 miles). Incredibly, Kittinger reached a maximum free-fall velocity of 614 miles per hour (Mach 0.92) passing through 90,000 feet.
The BMSP worked as advertised. Kittinger entered the cloud deck obscuring his Tularosa Basin landing point at 21,000 feet. Main parachute deployment occurred at 17,500 feet. Total elapsed time from bailout to touchdown was 13 minutes and 45 seconds.
While Joe Kittinger and the Excelsior team focused on flight testing technology critical to the survival of fellow aviators, a byproduct of their efforts were aviation records that stand to this very day. Those achievements include: highest parachute jump (102,800 feet), longest free-fall duration (4 minutes 36 seconds), and longest free-fall distance (85,300 feet).
Forty-three years ago today, the Lunar Orbiter 1 spacecraft began its 92 hour trip to the Moon. Lunar Orbiter 1 rode into space aboard an Atlas-Agena D launch vehicle which lifted-off from Pad 13 at Cape Canaveral, Florida. Lift-off time was 19:26 UTC on Wednesday, 10 August 1966.
Lunar Orbiter 1 was the first of five moon mapping missions launched over a period of 12 months as part of the Lunar Orbiter Program. The primary purpose of this program was to thoroughly map the surface of Earth’s nearest neighbor in space preparatory to the historic Apollo lunar landings.
At 15:34 UTC on Sunday, 14 August 1966, Lunar Orbiter 1 was inserted into a highly elliptical lunar orbit that measured 117.5 miles by 1,160 miles. Orbital plane inclination and period of the 850-pound spacecraft was 12.2-deg and 208-minutes, respectively. By Friday, 26 August 1966, the Lunar Orbiter 1 perilune had been lowered to just 25.2-miles.
Lunar Orbiter 1 took photographs of the lunar surface between 18 August and 29 August. Onboard film processing was completed by 30 August and transmission to Earth of 211 high and medium resolution photographs was completed at 20:02 UTC on Wednesday, 14 September 1966. This event, which occurred on Mission Day 35, marked the completion of the photographic portion of the spacecraft’s mission.
Lunar Orbiter 1 imaged nearly 2 million square miles of the Moon’s surface to a resolution of 200 feet or better. This was 10 times better than that obtained from earth-based cameras. Lunar Orbiter 1 also provided the first views of earth as seen from the Moon.
Lunar Orbiter 1 would continue to orbit the Moon for another 45 days. As it did so, the spacecraft provided a wealth of micrometeoroid, gravitational, and radiation measurements that helped lunar scientists better understand the complex lunar environment.
The Lunar Orbiter 1 mission ended on Saturday, 29 October 1966 (Mission Day 80) during its 577th lunar orbit. This intentional action was necessary to make way for the next Lunar Orbiter mission in November. The impact site is located at 6.35-deg N and 160.72-deg E on the far side of the Moon.
Fifty-eight years ago this week, a United States Navy Viking rocket soared to an altitude of 136 miles. In doing so, it eclipsed the previous single stage altitude record of 114 miles set by a captured German V-2 rocket on Tuesday, 17 December 1946. The mission was part of the Navy’s 12-flight Viking Rocket flight test series conducted between May 1949 and February 1955.
At 1659 UTC on Tuesday, 07 August 1951, Viking No. 7 was fired from LC-33 at White Sands Proving Ground (WSPG), New Mexico. Burnout velocity was 5,865 feet per second following a rocket motor burn time of 72 seconds. Viking No. 7 weighed 10,730 pounds at lift-off (roughly 8,000 pounds of which were propellants) and carried a scientific payload of 394 pounds.
Viking No. 7 was the last of the early Viking rocket configurations which measured 49-feet in length and had a diameter of 32-inches. Starting with Viking No. 8, the rocket’s airframe was modified to carry more propellants for greater altitude performance and measured 42-feet (length) by 45-inches (diameter). This modification allowed Viking No. 11, flown from WSPG on Monday, 24 May 1954, to capture the all-time Viking altitude record of 158 miles.
Although almost forgotten today, the Viking Rocket Program played a vital role in the history of American rocketry. Viking was the first large, liquid-fueled rocket developed by the United States. It’s rocket motor generated 21,000 pounds of lift-off thrust and employed an innovative two-axis gimbal system for pitch and yaw control. Fin-mounted reaction jets provided roll control.
The Viking Rocket Program provided a tremendous amount of scientific data about Earth’s atmospheric properties such as pressure, temperature, density, winds, and composition. Additionally, Viking formed the technological basis for a number of 1950’s rocket systems including the Navy’s Vanguard satellite launcher and the USAF Titan ICBM.
Forty years ago today, Apollo 11 astronauts Neil A. Armstrong, Edwin E. Aldrin, Jr., and Michael Collins arrived back at the Johnson Spacecraft Center (MSC) in Houston, Texas following their epic journey to and safe return from the Moon.
Following splashdown in the Pacific Ocean on Thursday, 24 July, 1969, the Apollo 11 astronauts and their Command Module Columbia were brought aboard the USS Hornet. Concerned that they would infect Earthlings with lunar pathogens, NASA quarantined the astronauts in the Mobile Quarantine Facility (MQF), which was a converted vacation trailer.
The Hornet steamed for Hawaii and transferred the MQF for airlift to Ellington Air Force Base, Texas. Following landing, the MQF and its heroic occupants were transported to the MSC. Once there, the astronauts and several medical staff were transferred from the MQF to more substantial accomodations known as the Lunar Receiving Laboratory (LRL).
Combined stay time in the MQF and LRL was 21 days. During their forced confinement, Armstrong, Aldrin, and Collins debriefed the Apollo 11 mission, rested, and mused about their unforgettable experiences at the Moon.
The Apollo 11 astronauts were released from the LRL on Thursday, 13 August 1969, having never contracted or transmitted a lunar disease.
Forty years ago today, the United States of America landed two men on the surface of the Moon.
The Apollo 11 Lunar Module Eagle landed in Sea of Tranquility region of the Moon on Sunday, 20 July 1969 at 20:17:40 UTC. Less than seven hours later, astronauts Neil A. Armstrong and Edwin E. Aldrin, Jr. became the first human beings to walk upon Earth’s closest neighbor. Fellow crew member Michael Collins orbited high overhead in the Command Module Columbia.
As Apollo 11 commander, Neil A. Armstrong was accorded the privilege of being the first man to step foot upon the Moon. As he did so, Armstrong spoke these words: “That’s one small step for Man; one giant leap for Mankind”. He had intended to say: “That’s one small step for ‘a’ man; one giant leap for Mankind”.
Armstrong and Aldrin explored their Sea of Tranquility landing site for about two and a half hours. Total lunar surface stay time was 22 hours and 37 minutes. The Apollo 11 crew left a plaque affixed to one of the legs of the Lunar Module’s descent stage which read: “Here Men From the Planet Earth First Set Foot Upon the Moon; July 1969, A.D. We Came in Peace for All Mankind”.
Following a successful lunar lift-off, Armstrong and Aldrin rejoined Collins in lunar orbit. Approximately seven hours later, the Apollo 11 crew rocketed out of lunar orbit to begin the quarter million mile journey back to Earth. Columbia splashed-down in the Pacific Ocean at 16:50:35 UTC on Thursday, 24 July 1969. Total mission time was 195 hours, 18 minutes, and 35 seconds.
With completion of the flight of Apollo 11, the United States of America fulfilled President John F. Kennedy’s 25 May 1961 call to land a man on the Moon and return him safely to the Earth before the decade of the 1960’s was out. It had taken 2,982 demanding days and much national treasure to do so.
Mission Accomplished, Mr. President.
Forty years ago this week, the epic flight of Apollo 11, the first mission to land men on the Moon, began with launch from the Kennedy Space Center (KSC) at Merritt Island, Florida. Nearly 1-million people gathered around America’s famous space complex to witness the historic event. An estimated 1-billion viewers worldwide watched the proceedings on television.
The names of the Apollo 11 crew are now legend: Mission Commander Neil A. Armstrong, Lunar Module Pilot Edwin E. Aldrin, Jr., and Command Module Pilot Michael Collins. Each astronaut was making his second spaceflight.
The overall Apollo 11 spacecraft weighed roughly 100,000 pounds and consisted of 3 major components: Command Module, Service Module, and Lunar Excursion Module (LEM). Out of American history came the names used to distinguish two of these components from one another. The Command Module was named Columbia, the feminine personification of America, while the Lunar Excursion Module received the appellation Eagle in honor of America’s national bird.
The Apollo-Saturn V launch stack measured 363-feet in length, had a maximum diameter of 33-feet, and weighed 6.7-milllion pounds at ignition of its five F-1 engines. The vehicle rose from the Earth on 7.7-million pounds of lift-off thrust.
The acoustic energy produced by the Saturn’s first stage propulsion system was unlike anything in common experience. The sound produced was like intense, continuous thunder even miles away from the launch point. Ground and structure shook disturbingly and a person’s lungs vibrated within their chest cavity.
Lift-off of Apollo 11 (AS-506) from KSC’s LC-39A occurred at 13:32 UTC on Wednesday, 16 July 1969. The target for the day’s launch, the Moon, was 218,096 miles distant from Earth. It took 12 seconds just for the massive Apollo 11 launch vehicle to clear the launch tower. However, a scant 12 minutes later, the Apollo 11 spacecraft was safely in low earth orbit (LEO) traveling at 17,500 miles per hour.
Following checkout in earth orbit, trans-lunar injection, and earth-to-moon coast, Apollo 11 entered lunar orbit nearly 76 hours after lift-off. Now, the big question: Would they make it? Even Apollo 11’s Command Module Pilot, Michael Collins, estimated that the chance of a successful lunar landing on the first attempt was only 50/50. The answer would soon come. History’s first lunar landing attempt was now only 24 hours away.
Thirty-three years ago this month, on the seventh anniversary of the first manned lunar landing, Viking I became the first spacecraft to successfully land on the surface of the planet Mars. The primary purpose of the mission was to search for signs of life on the Martian surface.
The Viking I mission began with launch from Earth on Wednesday, 20 August 1975. Lift-off of the Titan IIIE-Centaur launch vehicle from Cape Canaveral, Florida took place at 2122 UTC. The Viking I orbiter-lander payload mass at lift-off was 7,766 lbs.
After chasing Mars for 11 months and 500,000,000 miles, Viking I entered Martian orbit on Saturday, 19 June 1976. The original plan called for a landing on Sunday, 04 July. However, imaging of the intended landing site from orbit revealed that a landing there would be a high risk venture. With this revelation, Viking project scientists went into high stress mode to locate a suitable alternate landing location.
On Tuesday, 20 August 1976, the Viking I lander separated from the Viking orbiter at 0851 UTC in preparation for the deorbit burn.
The Viking I atmospheric deceleration sequence began at roughly 1,000,000 feet above the Martian surface. An ablating aeroshell both slowed and protected the vehicle from aerodynamic heating down to 19,000 feet. At this point, a 52.5-foot diameter parachute was deployed to provide further slowing. At 4,000 feet, the aeroshell and parachute were jettisoned and the craft’s retro-rockets were fired
The Viking I lander touched-down at Chryse Planitia (“Golden Plain” in the Greek) at 1153 UTC having completed the first successful Martian entry, descent, and landing (EDL) mission. The Viking I landing mass was on the order of 1,320 lbs. (Point of clarification: the photo above was taken by Viking II which landed on Mars at Utopia Planitia (“Nowhere Plain”) on Friday, 03 September 1976.)
Viking I went on to perform a variety of first-ever scientific investigations on Mars. Key instrumentation included several cameras, a surface sampler arm, a meterology boom, a seismometer, and a variety of other sensors. In its search for signs of life, Viking I was also configured with an internal biology compartment and gas chromatograph mass spectrometer.
The Viking I lander was designed to function for a minimum of 90 days on the surface of Mars. In reality, it continued to function and provide useful science for over 6 years (contact lost 13 November of 1982). While it rewrote the book in terms of Martian planetary science, Viking I did not in fact discover defintive signs of life on Mars.
On Saturday, 29 June 1957, the USAF/Convair XB-58A (S/N 55-660) first attained its double-sonic design airspeed when it flew to Mach 2.03 at an altitude of 43,250 feet. This historic achievement took place on the type’s 24th flight. The mission totaled 1 hour and 55 minutes and was commanded by Convair test pilot B. A. Erickson
The B-58A Hustler was the United States first supersonic-capable bomber and was originally designed for the strategic mission. The aircraft was powered by four (4) General Electric J79-GE-5A turbojets generating 62,400 lbs of sea level thrust in afterburner. Maximum take-off weight was nearly 177,000 lbs.
Convair’s stunning delta-winged bomber was 97 feet in length with a wing span of 57 feet. Wing area was roughly 1,550 square feet. Aircraft maximum height was 30 feet as measured from the ground to the top of the vertical tail.
Flight crew for the B-58A consisted of the pilot, bombadier/navigator, and defensive systems operator. The crew was arranged in tandem with each crew member seated in a separate cockpit. The type carried thermonuclear ordnance. A total of 116 B-58A aircraft were manufactured.
The B-58A performance was impressive then and now. It had a maximum speed of 1,400 mph and a service ceiling of 63,400 feet. The aircraft could climb in excess of 17,000 feet per minute at gross take-off weight and up to 46,000 feet per minute near minimum weight.
The B-58A had a difficult gestation due to its advanced design and demanding performance requirements. A large number of aircraft and flight crews were lost due to a variety of flight control and structural problems. First flight took place on 11 November 1956 with the type finally entering the USAF inventory on 15 March 1960.
The USAF/Convair B-58A Hustler was operational for nearly 10 years and was retired on 31 January 1970. The aircraft was never used in anger.
On Monday, 21 June 2004, Scaled Composite’s SpaceShipOne flew to an altitude of 62.214 statute miles. The flight marked the first time that a privately-developed flight vehicle had flown above the 62-statute mile boundary that entitles the flight crew to FAI-certified astronaut wings. As a result, SpaceShipOne pilot Mike Melvill became history’s first private citizen astronaut.
SpaceShipOne Mission 15P began with departure from California’s Mojave Spaceport at 0647 PDT. Carrying SpaceShipOne at the centerline station, Scaled’s White Knight aircraft climbed to the drop altitude of 47,000 feet.
At 0750 PDT, the 7,900-pound SpaceShipOne fell away from the White Knight and Melvill immediately ignited the 16,650-pound thrust hybrid rocket motor. Melvill quickly then pulled SpaceShipOne into a vertical climb.
Passing through 60,000 feet, SpaceShipOne experienced a series of uncommanded rolls as it encountered a wind shear. Melvill struggled with the controls in an attempt to arrest the roll transient. Then, late in the boost, the vehicle lost primary pitch trim control. In response, Melvill switched to the back-up system as he continued the ascent.
Rocket motor burnout occurred at 180,000 feet with SpaceShipOne traveling at 2,150 mph. It now only weighed 2,600 pounds. The vehicle then coasted to an apogee of 62.214 statute miles (328,490 feet). The target maximum altitude was 68.182 statute miles (360,000 feet). However, the control problems encountered going upstairs caused the trajectory to veer somewhat from the vertical.
Melvill experienced approximately 3.5 minutes of zero-g flight going over the top. He had some fun during this period as he released a bunch of M&M’s and watched the chocolate candy pieces float in the SpaceShipOne cabin.
Back to business now, Melvill transitioned SpaceShipOne to the high-drag feathered configuration in preparation for the critical entry phase of the mission. The vehicle initially accelerated to over 2,100 mph in the airless void before encountering the sensible atmosphere. At one point during atmospheric entry, Melvill experienced in excess of 5 g’s deceleration.
At 57,000 feet, Melvill reconfigured SpaceShipOne back to the standard aircraft configuration for powerless flight back to the Mojave Spaceport. Fortunately, the aircraft was a very good glider. The control problems encountered during the ascent resulted in atmospheric entry taking place 22 statute miles south of the targeted reentry point.
SpaceShipOne touched-down on Mojave Runway 12/30 at 0814 PDT; thus ending an historic, if not harrowing mission.
After the flight, Mike Melvill had much to say. But perhaps the following quote says it best for the rest of us who can only imagine what it was like: “And it was really an awesome sight, I mean it was like nothing I’ve ever seen before. And it blew me away, it really did. … You really do feel like you can reach out and touch the face of God, believe me.”
Forty-four years ago this month, Astronaut Edward H. White II became the first American to perform what in NASA parlance is referred to as an Extra Vehicular Activity (EVA). In simple terms; a space walk.
White, Mission Commander James A. McDivitt and their Gemini IV spacecraft were launched into low Earth orbit by a two-stage Titan II launch vehicle from LC-19 at Cape Canaveral Air Force Station, Florida. The mission clock started at 15:15:59 GMT on Thursday, 03 June 1965.
On the third orbit, less than five hours after launch, White opened the Gemini IV starboard hatch. He stood in his seat and mounted a camera to capture his historic space stroll. He then cast-off from Gemini IV and became a human satellite.
White was tethered to Gemini IV via a 15-foot umbilical that provided oxygen and communications to his EVA suit. A gold-plated visor on his helmet protected his eyes from the harsh glare of the sun. The space-walking astronaut was also outfitted with a hand-held maneuvering unit that used compressed oxygen to power its small thrusters. And, like any good tourist, he also took along a camera.
Ed White had the time of his all-too-brief life in the 22 minutes that he walked in space. The sight of the earth, the spacecraft, the sun, the vastness of space, the freedom of movement all combined to make him exclaim at one point, “I feel like a million dollars!”.
Presently, it was time to get back into the spacecraft. But, couldn’t he just stay outside a little longer? NASA Mission Control and Commander McDivitt were firm. It was time to get back in; now! He grudgingly complied with the request/order, plaintively saying: “It’s the saddest moment of my life!”
As Ed White got back into his seat, he and McDivitt struggled to lock the starboard hatch. Both men were exhausted, but ebullient as they mused about the successful completion of America’s first space walk.
Gemini IV would eventually orbit the Earth 62 times before splashing-down in the Atlantic Ocean at 17:12:11 GMT on Sunday, 07 June 1965. The 4-day mission was another milestone in America’s quest for the moon.
The mission was over and yet Ed White was still a little tired. But then, that was easy to understand. In the time that he was outside the spacecraft, Gemini IV had traveled almost a third of the way around the world.
Now, that’s a long walk.
Forty-three years ago today, XB-70A Valkyrie Air Vehicle No. 2 (62-0207) took-off from Edwards Air Force Base, California for the final time.
The crew for this flight included aircraft commander and North American test pilot Alvin S. White and right-seater USAF Major Carl S. Cross. White would be making flight No. 67 in the XB-70A while Cross was making his first. For both men, this would be their final XB-70A flight.
In the past several months, Air Vehicle No. 2 had set speed (Mach 3.08) and altitude (74,000 feet) records for the type. But on this fateful day, 08 June 1966, the mission was a simple one; some minor flight research test points and a photo shoot.
The General Electric Company, manufacturer of the massive XB-70A’s YJ93-GE-3 turbojets, had received permission from Edwards USAF officials to photograph the XB-70A in close formation with a quartet of other aircraft powered by GE engines. The resulting photos were intended to be used for publicity.
The formation, consisting of the XB-70A, a T-38A (59-1601), an F-4B (BuNo 150993), an F-104N (N813NA), and an F-5A (59-4898), was in position at 25,000 feet by 0845. The photographers for this event, flying in a GE-powered Gates Learjet (N175FS) stationed about 600 feet to the left and slightly aft of the formation, began taking photos.
The photo session was planned to last 30 minutes, but went 10 minutes longer to 0925. Then at 0926, just as the formation aircraft were starting to leave the scene, the frantic cry of Midair! Midair Midair! came over the communications network.
Somehow, the NASA F-104N, piloted by NASA Chief Test Pilot Joe Walker, had collided with the right wing-tip of the XB-70A. Walker’s out-of-control F-104 then rolled inverted to the left and sheared-off the XB-70A’s twin vertical tails. The F-104N fuselage was severed just behind the cockpit and Walker died instantly in the process.
Curiously, the XB-70A continued on in steady, level flight for about 16 seconds despite the loss of its primary directional stability lifting surfaces. Then, as White attempted to control a roll transient, the XB-70A rapidly departed controlled flight.
As the doomed aircraft torturously pitched, yawed and rolled, its left wing structurally failed and fuel spewed furiously from its fuel tanks. White was somehow able to eject and survive. Cross never left the aircraft and rode it down to impact just north of Barstow, California.
A mishap investigation followed and (as always) blame was assigned. However, none of that changed the facts that on this, the Blackest Day at Edwards, American aviation lost two of its best men and aircraft in a flight mishap that never should have happened.
White Eagle Aerospace History Blog 
