Sixty-seven years ago today, the USAF/Bell XS-1 became the first aircraft of any type to achieve supersonic flight during a climb from a ground take-off. The daring feat took place at Muroc Air Force Base with USAF Captain Charles E. “Chuck” Yeager at the controls of the rocket-powered 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 capability 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 originally designed to be ground-launched.
In the best tradition of inter-service rivalry, the Navy claimed that the D-558-I at the time 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 served!
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 somewhat fragile landing gear, the XS-1 propellant load was restricted to 50% of capacity. This provided approximately 100 seconds of rocket-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 only 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 desert 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 a test pilot named Chuck Yeager who brought victory home to the blue suiters.
Forty-seven years ago this month, three American astronauts became the first men to orbit the Earth’s Moon during the flight of Apollo 8. This epic mission also featured the first manned flight of the mighty Saturn V launch vehicle 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, it may be said that Apollo 8 saved the entire Apollo Program.
Fifty 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 or nearly fourteen days.
Project Gemini was the critical bridge between America’s fledgling 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 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 space faring activity had come just 20 days previous. Indeed, Alan B. Shepard 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 Seven (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. The astronauts 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 comfort 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 recovery ship. 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 demanding existence, the Gemini 7 crew did their job. Gemini 7 was a resounding success. More, Project Gemini had achieved another key milestone. The Moon now seemed a bit closer.
Fifty-six years ago today, 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.
Sixty-two years ago this week, 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, the legendary test pilot very 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.
Fifty-six years ago this month, a USAF/Convair F-106A Delta Dart interceptor was clocked at 1,525.695 mph on an 11-mile straight course at Edwards Air Force Base, California. This mark still stands as an absolute speed record for a single-engine turbojet-powered aircraft.
The USAF/Convair F-106 Delta Dart was designed for the all-weather interceptor role in defense of CONUS. As such, the Delta Dart’s primary mission was to seek out Soviet bomber formations and destroy same using its internally-carried missiles. Armament consisted of either (1) a quartet of Hughes AIM-4 Falcon missiles and a single AIM-26A Falcon missile or (2) a single Douglas AIR-2 Genie missile.
A member of the fabled Century Series, the Delta Dart was produced in two variants. The single place version was known as the F-106A while the dual place version was designated as the F-106B. Though primarily a trainer, this aircraft was also combat-capable. A total of 340 Delta Dart aircraft were manufactured by Convair; 277 F-106A’s and 63 F-106B’s.
The F-106A Delta Dart measured 70.7 feet in length and had a wing span of 38.25 feet. Gross Take-Off Weight (GTOW) and Empty Weight were 34,510 lbs and 24,420 lbs, respectively. Power was supplied by a single Pratt and Whitney J75-17 afterburning turbojet which produced 24,500 lbs of thrust at sea level.
The sleek Delta Dart was aerodynamically very clean. This was due in large measure to use of fuselage area ruling and a thin delta planform wing. The F-106A could climb at 29,000 feet per minute and had a service ceiling of 57,000 feet. Maximum unrefueled range was on the order of 2,700 nm.
Due to its impressive performance, USAF employed the F-106A in an attempt to regain the single-engine absolute speed record from the Soviets in late 1959. The existing record of 1,483.84 mph had been established in 1956 by a Soviet Ye-66 aircraft specially designed for setting the speed mark. The Air Force’s absolute speed record attempt was codenamed Project Firewall.
USAF originally selected F-106A (S/N 56-0459) to make the 1959 absolute speed record attempt. The aircraft was modified slightly to optimize its speed performance. However, 56-0459 experienced engine compressor stall problems and did not set the actual record. Rather, an unmodified F-106A (S/N 56-0467) was called into service and set the speed record reported here.
On Tuesday, 15 December 1959, USAF Major Joseph W. Rogers departed Edwards Air Force Base in a quest to establish a new absolute speed record for a single-engine turbojet-powered aircraft. Flying at 40,000 feet, Rogers and his F-106A averaged 1,525.695 mph over an 11-mile straight course to set a new speed mark.
For his remarkable airmanship on Project Firewall, Joe Rogers was presented with the Distinguished Flying Cross, the DeLavaulx Medal, and the Thompson Trophy. Rogers went on to a remarkable military career spanning 29 years. He retired in 1975 as a full colonel.
For its part, the Delta Dart went on to a 28-year operational life (1959-1987) with the United States Air Force and the Air National Guard. Considered by many to be the finest interceptor in aviation history, the Delta Dart is known to this day as the Ultimate Interceptor.
Forty-eight 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, perished when his aircraft was ripped 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.
Eleven 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 eclipsed 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.
Fifty-four 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.
Thirty-four 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 records that this projected flight rate was much too optimistic.
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. The final mission of the Space Shuttle Program (STS-135) was flown by Atlantis in July 2011.
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.
