Tag Archives: Bell Aircraft Corporation

14 October 1947

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Captain Charles Elwood (“Chuck”) Yeager, U.S. Air Force, with “Glamorous Glennis,” the Bell XS-1. (U.S. Air Force/National Air and Space Museum)

14 October 1947: At approximately 10:00 a.m., a four-engine Boeing B-29 Superfortress heavy bomber, piloted by Major Robert L. Cardenas, took off from Muroc Air Force Base (now known as Edwards Air Force Base) in the high desert north of Los Angeles, California. The B-29’s bomb bay had been modified to carry the Bell XS-1, a rocket-powered airplane designed to investigate flight at speeds near the Speed of Sound (Mach 1).

A Bell XS-1 rocketplane carried aloft in the bomb bay of a modified Boeing B-29-96-BW Superfortress, serial number 45-21800. (NASA)
Captain Chuck Yeager with the Bell XS-1 on Muroc Dry Lake, 1947. (Chuck Yeager collection)

Air Force test pilot Captain Charles Elwood (“Chuck”) Yeager, a World War II fighter ace, was the U.S. Air Force pilot for this project. The X-1 airplane had been previously flown by company test pilots Jack Woolams and Chalmers Goodlin. Two more X-1 aircraft were built by Bell, and the second, 46-063, had already begun its flight testing.

Captain Yeager had made three glide flights and this was to be his ninth powered flight. Like his P-51 Mustang fighters, he had named this airplane after his wife, Glamorous Glennis.

Bob Cardenas climbed to 20,000 feet (6,096 meters) and then put the B-29 into a shallow dive to gain speed. In his autobiography, Yeager wrote:

“One minute to drop. [Jack] Ridley flashed the word from the copilot’s seat in the mother ship. . . Major Cardenas, the driver, starts counting backwards from ten. C-r-r-ack. The bomb shackle release jolts you up from your seat, and as you sail out of the dark bomb bay the sun explodes in brightness. You’re looking at the sky. Wrong! You should have dropped level. The dive speed was too slow, and they dropped you in a nose-up stall. . .

Cockpit of Bell X-1, 46-062, Glamorous Glennis, on display at the National Air and Space Museum. (Photo by Eric Long, National Air and Space Museum, Smithsonian Institution)

“I fought it with the control wheel for about five hundred feet, and finally got her nose down. The moment we picked up speed I fired all four rocket chambers in rapid sequence. We climbed at .88 Mach. . . I turned off two rocket chambers. At 40,000 feet, we were still climbing at .92 Mach. Leveling off at 42,000 feet, I had thirty percent of my fuel, so I turned on rocket chamber three and immediately reached .96 Mach. . . the faster I got, the smoother the ride.

“Suddenly the Mach needle began to fluctuate. It went up to .965 Mach—then tipped right off the scale. . . .”

—Brigadier General Charles E. Yeager, U.S. Air Force (Retired), Yeager, An Autobiography, by Chuck Yeager and Leo Janos, Bantam Books, New York, 1985, Pages 120, 129–130.

In his official report of the flight, Yeager wrote:

Date: 14 October 1947

Pilot: Captain Charles E. Yeager

Time: 14 Minutes

       9th Powered Flight

1. After normal pilot entry and subsequent climb, the XS-1 was dropped from the B-29 at 20,000′and at 250 MPH ISA. This was slower than desired.

2. Immediately after drop, all four cylinders were turned on in rapid sequence, their operation stabilizing at the chamber and line pressure reported in the last flight. The ensuing climb was made at .85–.88 Mach, and, as usual, it was necessary to change the stabilizer setting to 2 degrees nose down from its pre-drop setting of 1 degree nose down. Two cylinders were turned off between 35,000′ and 40,000′,  but speed had increased to .92 Mach as the airplane was leveled off at 42,000′. Incidentally, during the slight push-over at this altitude, the lox line pressure dropped perhaps 40 psi and the resultant rich mixture caused chamber pressures to decrease slightly. The effect was only momentary, occurring at .6 G’s, and all pressures returned to normal at 1 G.

3. In anticipation of the decrease in elevator effectiveness at speeds above .93 Mach, longitudinal control by means of the stabilizer was tried during the climb at .83, .88, and .92 Mach. The stabilizer was moved in increments of 1/4–1/3 degree and proved to be very effective; also, no change in effectiveness was noticed at the different speeds.

4. At 42,000′ in approximately level flight, a third cylinder was turned on. Acceleration was rapid and speed increased to .98 mach. The needle of the machmeter fluctuated at this reading momentarily, then passed off the scale. Assuming that the offscale reading remained linear, it is estimated that 1.05 Mach was attained at this time. Approximately 30% of fuel and lox remained when this speed was reached and the meter was turned off.

5. While the usual light buffet and instability characteristics were encountered in the .88–.90 Mach range and elevator effectiveness was very greatly decreased at .94 Mach, stability about all three axes was good as speed increased and elevator effectiveness was regained above .97 Mach. As speed decreased after turning off the motor, the various phenomena occurred n reverse sequence at the usual speed, and in addition, a slight longitudinal porpoising was noticed from .98–.96 Mach which controllable by the elevators alone. Incidentally, the stability setting was not changed from its 2 degree nose down position after trial at .92 Mach.

6. After jettisoning the remaining fuel and lox a 1 G stall was performed at 45,000′. The flight was concluded by the subsequent glide and a normal landing on the lake bed.

CHARLES E. YEAGER
Capt., Air Corps

Chuck Yeager and flown the XS-1 through “the sound barrier,” something many experts had believed might not be possible. His maximum speed during this flight was Mach 1.06 (699.4 miles per hour/1,125.7 kilometers per hour).

Bell X-1 46-062 in flight. Note the “shock diamonds” visible in the rocket engine’s exhaust. (Photograph by Lieutenant Robert A. Hoover, U.S. Air Force)

The Bell XS-1, later re-designated X-1, was the first of a series of rocket powered research airplanes which included the Douglas D-558-II Skyrocket, the Bell X-2, and the North American Aviation X-15, which were flown by the U.S. Air Force, U.S. Navy, NACA and its successor, NASA, at Edwards Air Force Base to explore supersonic and hypersonic flight and at altitudes to and beyond the limits of Earth’s atmosphere.

The X-1 is shaped like a bullet and has straight wings and tail surfaces. It is 30 feet, 10.98 inches (9.423 meters) long with a wing span of 28.00 feet (8.534 meters) and overall height of 10 feet, 10.20 inches (3.307 meters). Total wing area is 102.5 square feet ( 9.5 square meters). At its widest point, the diameter of the X-1 fuselage is 4 feet, 7 inches (1.397 meters). The empty weight is 6,784.9 pounds (3,077.6 kilograms), but loaded with propellant, oxidizer and its pilot with his equipment, the weight increased to 13,034 pounds (5,912 kilograms). The X-1 was designed to withstand an ultimate structural load of 18g.

The X-1 is powered by a four-chamber Reaction Motors, Inc., XLR11-RM-3 rocket engine which produced 6,000 pounds of thrust (26,689 Newtons). This engine burns a mixture of ethyl alcohol and water with liquid oxygen. Fuel capacity is 293 gallons (1,109 liters) of water/alcohol and 311 gallons (1,177 liters) of liquid oxygen. The fuel system is pressurized by nitrogen at 1,500 pounds per square inch (10,342 kilopascals).

The X-1 was usually dropped from a B-29 flying at 30,000 feet (9,144 meters) and 345 miles per hour (555 kilometers per hour). It fell as much as 1,000 feet (305 meters) before beginning to climb under its own power.

The X-1’s performance was limited by its fuel capacity. Flying at 50,000 feet (15,240 meters), it could reach 916 miles per hour (1,474 kilometers per hour), but at 70,000 feet (21,336 meters) the maximum speed that could be reached was 898 miles per hour (1,445 kilometers per hour). During a maximum climb, fuel would be exhausted as the X-1 reached 74,800 feet (2,799 meters). The absolute ceiling is 87,750 feet (26,746 meters).

The X-1 had a minimum landing speed of 135 miles per hour (217 kilometers per hour) using 60% flaps.

Bell X-1 46-063 with its Boeing B-29 Superfortress carrier aircraft, 45-21800. (Flight Test Historical Foundation)

The three X-1 rocketplanes made a total of 157 flights with the three X-1. The number one ship, Glamorous Glennis, made 78 flights. On 26 March 1948, with Chuck Yeager again in the cockpit, it reached reached Mach 1.45 (957 miles per hour/1,540 kilometers per hour) at 71,900 feet (21,915 meters).

The third X-1, 46-064, made just one glide flight before it was destroyed 9 November 1951 in an accidental explosion.

The second X-1, 46-063, was later modified to the X-1E. It is on display at the NASA Dryden Research Center at Edwards Air Force Base.

Glamorous Glennis is on display at the Smithsonian Institution National Air and Space Museum, next to Charles A. Lindbergh’s Spirit of St. Louis.

Bell X-1, 46-062, Glamorous Glennis, on display in the Milestones of Flight gallery at the National Air and Space Museum, Washington, D.C. (Photo by Eric Long, National Air and Space Museum, Smithsonian Institution)

© 2017, Bryan R. Swopes

14 October 1944

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Ann Gilpin Baumgartner, circa 1944. (National Air and Space Museum)

14 October 1944: Ann Gilpin Baumgartner, a member of the Women Airforce Service Pilots (WASPs) assigned as Assistant Operations Officer of the Fighter Section, Flight Test Division, at Wright Field, Dayton, Ohio, made an evaluation flight of the Bell YP-59A Airacomet, becoming the first woman to fly a turbojet-propelled airplane.

The Airacomet was designed and built by the Bell Aircraft Corporation as an interceptor, powered by two turbojet engines. There were three XP-59A prototypes. The first one flew at Muroc Army Airfield on 1 October 1942. The Army Air Corps had ordered thirteen YP-59A service test aircraft. The first of these flew in August 1943 at Muroc.

The Bell YP-59A was conventional single place airplane with retractable tricycle landing gear. It was primarily of metal construction, though the control surfaces were fabric-covered. Its dimensions differed slightly from the XP-59A, having shorter wings with squared of tips, and a shorter, squared, vertical fin. There were various other minor changes, but the exact specifications of the YP-59As are uncertain.

Bell YP-59A-BE Airacomet 42-108775 at Wright Field. (U.S. Air Force)

The primary difference, though, was the change from the General Electric I-A turbojet to the I-16 (later designated J31-GE-1). Both were reverse-flown engines using a single-stage centrifugal compressor and a single-stage turbine. The I-16 produced 1,610 pounds of thrust (7.16 kilonewtons). They were 6 feet, 0 inches long, 3 feet, 5.5 inches in diameter and weigh 865 pounds (392 kilograms),

Even with the two I-16s producing 720 pounds of thrust (3.20 kilonewtons) more than the the XP-59A’s I-A engines, the YP-59A’s performance did not improve. Engineers had a lot to learn about turbojeft engine inlet design.

The YP-59A had a maximum speed of 409 miles per hour (658 kilometers per hour) at 35,000 feet (10,668 meters), and its service ceiling was 43,200 feet (13,167 meters).

Bell YP-59A-BE Airacomet 42-108775 at Wright Field. (U.S. Air Force)

The P-59 was ordered into production and Bell Aircraft Corporation built thirty P-59A and twenty P-59B fighters. These were armed with one M4 37mm autocannon with 44 rounds of ammunition and three Browning AN-M2 .50-caliber machine guns with 200 rounds per gun.

Although a YP-59A had set an unofficial altitude record of 47,600 feet (14,508 meters), the Airacomet was so outclassed by standard production fighters that no more were ordered.

Bell YP-59A-BE Airacomet 42-108775 at Wright Field. (U.S. Air Force)
Ann G. Baumgartner stands on the wing of a North American Aviation T-6 Texan. (U.S. Air Force)

Ann Gilpin Baumgartner was born 27 Aug 1918, at the U.S. Army Hospital, Fort Gordon, Augusta, Georgia. She was the daughter of Edgar F. Baumgartner, engineer and patent attorney, and Margaret L. Gilpin-Brown Baumgartner. After graduating from Walnut Hill High School, Natick, Massachussetts, she studied pre-med at Smith College, Northampton, Massachussetts. She played soccer and was on the swimming team. She graduated in 1939.

Miss Baumgartner worked as a reporter for The New York Times. She took flying lessons at Somerset Hills Airport, Basking Ridge, New Jersey, and soloed after only eight hours. She then bought  Piper Cub to gain flight experience.

Ann G. Baumgartner, WASP Class 43-W-3. (U.S. Air Force)

After being interviewed by Jackie Cochran, Baumgartner joined the Women Airforce Service Pilots (WASPs) 23 March 1943, a member of Class 43-W-3, graduating 11 September 1943 with Class 43-W-5. She was then assigned to Camp Davis Army Airfield, Holly Ridge, North Carolina, where she towed targets for anti-aircraft artillery training.

Miss Baumgartner  was transferred to Wright Field, Dayton, Ohio (now, Wright-Patterson Air Force Base), where she flew the B-24 Liberator and B-29 Superfortress heavy bombers, P-38 Lightning, P-47 Thunderbolt, YP-59A Airacomet, P-82 Twin Mustang fighters, and the Luftwaffe Junkers Ju 88 medium bomber.

While at Wright Field, Miss Baumgartner met Major William Price Carl, who was an engineer associated with the P-82. They were married 2 May 1945, and would have two children.

Miss Baumgartner was released from service 20 December 1944, when the WASPs were disbanded. Following World War II, she was employed as an instrument flight instructor for United Air Lines.

After they retired, Mr. and Mrs. Carl sailed the Atlantic Ocean aboard their sailboat, Audacious.

Mrs. Carl was the author of A WASP Among Eagles and The Small World of Long-Distance Sailors.

Ann Gilpin Baumgartner Carl died at Kilmarnock, Virginia, 20 March 2008, at the age of 89 years. She and her husband, who had died one month earlier, were buried at sea.

Mrs. Ann Baumgartner Carl (1918–2008)

© 2017 Bryan R. Swopes

8 October 1954

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Captain Arthur W. Murray, U.S. Air Force (1918–2011). Murray is wearing a David Clark Co. T-1 capstan-type partial-pressure suit with K-1 helmet for high altitude flight. (U.S. Air Force)
Captain Arthur W. Murray, U.S. Air Force (1918–2011). Murray is wearing a David Clark Co. T-1 capstan-type partial-pressure suit. (U.S. Air Force)

8 October 1954: After two earlier glide flights flown by test pilot Jack Ridley, Captain Arthur Warren (“Kit”) Murray, U.S. Air Force, made the first powered flight of the Bell Aircraft Corporation X-1B rocket-powered supersonic research aircraft, serial number 48-1385.

Five months earlier, Murray had flown the X-1A to an altitude of 90,440 feet (25,570 meters). He was the first pilot to fly high enough to see the curvature of the Earth and a dark sky at mid day.

The X-1B was the third in a series of experimental X-1 rocketplane variants built by the Bell Aircraft Corporation for the United States Air Force and the National Advisory Committee for Aeronautics (NACA), for research into supersonic flight. It was fitted with 300 thermocouples to measure aerodynamic heating. It was the first aircraft equipped with a pilot-controlled reaction control system which allowed for maneuvering the aircraft at high altitudes where normal aerodynamic controls were no longer effective.

NACA 800, a modified Boeing B-29 Superfortress, 45-21800, with the Bell X-1B, at Edwards Air Force Base, 8 April 1958. (NASA)
NACA 800, a modified Boeing B-29 Superfortress, 45-21800, with the Bell X-1B, at Edwards Air Force Base, 9 April 1958. (NASA)

Like the X-1 and X-1A, the X-1B was carried by a modified four-engine B-29 Superfortress heavy bomber (B-29-96-BW 45-21800), before being airdropped at altitudes of 25,000 to 35,000 feet (7,620 to 10,668 meters) near Edwards Air Force Base, California. After its fuel was expended, the pilot would glide for a landing on Rogers Dry Lake.

The X-1B was 35 feet, 7 inches (10.846 meters) long with a wing span of 28 feet (8.53 meters). Its loaded weight was 16,590 pounds (7,520 kilograms). The X-1B was powered by a Reaction Motors XLR11-RM-6 four-chamber rocket engine, fueled with a mixture of water and alcohol with liquid oxygen. It produced 6,000 pounds of thrust (26.689 kilonewtons. The XLR11 was 5 feet, 0 inches (1.524 meters) long, 1 foot, 7 inches (0.483 meters) in diameter, and weighed 210 pounds (95 kilograms). Each of the four thrust chambers were 1 foot, 9¾ inches (0.552 meters) long and 6 inches (0.152 meters) in diameter.

The rocket plane was designed to reach 1,650 miles per hour (2,655 kilometers per hour) and 90,000 feet (27,432 meters).

Bell X-1B (Bell Aircraft Corporation)
Bell X-1B 46-1385 (U.S. Air Force)
Bell X-1B 46-1385 on Rogers Dry Lake (NASA E-2547)
Bell X-1B on Rogers Dry Lake (NASA)
Bell X-1B 46-1385 on Rogers Dry Lake (NASA)

This was Kit Murray’s only flight in the X-1B. After being flown by a number of other Air Force test pilots, including Stuart Childs and Frank Everest, the rocketplane was turned over to NACA for the continued flight test program. NACA research pilots John McKay and Neil Armstrong made those flights.

X-1B 48-1385 made 27 flights. It was retired in January 1958. It is in the collection of the National Museum of the United States Air Force at Wright-Patterson Air Force Base, Ohio.

Bell X-1B 46-1385 parked on Rogers Dry Lake, 30 July 1958. (NASA)
Bell X-1B 46-1385 parked on Rogers Dry Lake, 30 July 1958. (NASA)
Bell X-1B 46-1385 parked on Rogers Dry Lake, 30 July 1958. (NASA)
Bell X-1B 46-1385 parked on Rogers Dry Lake, 30 July 1958. (NASA)

Arthur Warren Murray was born at Cresson, Cambria County, Pennsylvania, 26 December 1918. He was the first of two children of Charles Chester Murray, a clerk, and Elsie Espy Murray.

Arthur Murray attended Huntingdon High School, Huntingdon, Pennsylvania, graduating 4 June 1936, and then studied Juniata College, also in Huntingdon, 1937–1938.

Kit Murray enlisted in the Field Artillery, Pennsylvania National Guard, 17 November 1939. (Some sources state that he served in the U.S. Cavalry.) Murray had brown hair and blue eyes, was 5 feet, 10 inches (1.78 meters) tall and weighed 150 pounds (68 kilograms). Following the United States’ entry into World War II, Sergeant Murray requested to be trained as a pilot. He was appointed a flight officer (a warrant officer rank), Army of the United States, on 5 December 1942. On 15 October 1943 Flight Officer Murray received a battlefield promotion to the commissioned rank of second lieutenant, A.U.S.

Between 6 January and 22 October 1943, Murray flew over 50 combat missions in the Curtiss-Wright P-40 Warhawk across North Africa. After about ten months in the Mediterranean Theater, he returned to the United States, assigned as an instructor flying the Republic P-47 Thunderbolt fighter bomber, stationed at Bradley Field, Hartford, Connecticut.

Lieutenant Murray married Miss Elizabeth Anne Strelic, who had immigrated from Czechoslovakia with her family as an infant, at Atlantic City, New Jersey, 29 December 1943. They would have six children, and foster a seventh. They later divorced. (Mrs. Murray died in 1980.)

Murray was promoted to 1st lieutenant, A.U.S., 8 August 1944. His next assignment was as a maintenance officer. He was sent to Maintenance Engineering School at Chanute Field, Rantoul, Illinois, and from there to the Flight Test School at Wright Field, Dayton, Ohio.

Murray was the first test pilot to be permanently assigned to Muroc Army Air Field (later, Edwards Air Force Base). Other test pilots, such as Captain Chuck Yeager, were assigned to Wright Field and traveled to Muroc as necessary.

Murray’s A.U.S. commission was converted to first lieutenant, Air Corps, United States Army, on 19 June 1947, with date of rank retroactive to 15 October 1946. The U.S. Air Force became a separate military service in 1947, and Lieutenant Murray became an officer in the new service.

Colonel Arthur Warren (“Kit”) Murray, U.S. Air Force.

Later, 1958–1960, Major Murray was the U.S. Air Force project officer for the North American Aviation X-15 hypersonic research rocketplane at Wright Field.

Colonel Murray retired from the U.S. Air Force in 1961. He next worked for Boeing in Seattle, Washington, from 1961 to 1969, and then Bell Helicopter in Texas.

On 4 April 1975, Kit Murray married his second wife, Ms. Ann Tackitt Humphreys, an interior decorator, in Tarrant County, Texas.

Colonel Arthur Warren Murray, United States Air Force (Retired), died at West, Texas, 25 July 2011, at the age of 92 years.

© 2018, Bryan R. Swopes

1 October 1942

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Bell XP-59A Airacomet 42-108784, first flight at Muroc Dry Lake, 1 October 1942. (U.S. Air Force)

1 October 1942: At Muroc Dry Lake, in the high desert north of Los Angeles, California, Bell Aircraft Corporation’s Chief Test Pilot, Robert Morris Stanley, made the first flight of the top secret prototype turbojet-powered fighter, the Bell XP-59A Airacomet, serial number 42-108784. Weather was “C.A.V.U.” (Ceiling and Visibility Unrestricted) and wind was from the west at 20 miles per hour (9 meters per second).

Bell Aircraft Corporation Chief Test Pilot Robert M. Stanley in the cockpit of an XP-59A Airacomet. (National Museum of the United States Air Force)

In his report, Stanley wrote:

4.     All take-offs were made using 15,000 r.p.m. on both engines with flaps fully up and with the airplane pulled off the ground at about 80 to 90 m.p.h. Throttle was applied promptly and acceleration during take-off appeared quite satisfactory. The run was estimated to be in the vicinity of 2,000 feet, possibly more. The first flight reached an altitude of approximately 25 feet, and landing was made using partial power without flaps. This take-off had the wind approximately 60° on the right bow and must be considered a cross-wind take-off.

5.     Aileron and elevator action appear satisfactory, although the rudder force appears undesirably light causing the airplane to yaw somewhat for very light pedal pressures. Left rudder was needed for take-off due to cross wind.

—Bell Aircraft Corp. Pilot’s Report 27-923-001, at Page 1-12, by Robert M. Stanley, 1 October 1942

Bell XP-59A Airacomet 42-108784 disguised with a false propeller. (U.S. Air Force)
One of the three Bell XP-59A prototypes, circa 1942. (U.S. Air Force)
Bell Aircraft Corporation XP-59A Airacomet 42-108784. (U.S. Air Force photo)
Bell Aircraft Corporation P-59 Airacomet with updated national insignia, after August 1943. (U.S. Air Force photo)
Bell Aircraft Corporation XP-59A Airacomet 42-108784. (U.S. Air Force photo)

Stanley made three more flights that day, as high as 100 feet (30.5 meters). The following day, Army Air Corps test pilot Colonel Laurence C. Craigie conducted the “official” first flight, reaching an altitude of 10,000 feet (3,048 meters).

A Bell XP-59A Airacomet prototype in flight near Muroc Army Airfield, 1942. (U.S. Air Force)

Three XP-59A prototypes were built. The number one ship, 42-108784, was affectionately nicknamed Miss Fire, because of the initial difficulty in getting the engines to start.

The Bell XP-59A was conventional single-place airplane with retractable tricycle landing gear. It was primarily of metal construction, though the control surfaces were fabric-covered. The prototype was 38 feet, 10 inches (11.836 meters) long with a wingspan of 49 feet, 0 inches (14.935 meters) and overall height of 12 feet, 3¾ inches (3.753 meters), at rest. The leading edge of the wings were swept aft  7°. The angle of incidence was +2° with -2° twist and 2½° dihedral. The horizontal stabilizer had a span of 16 feet, 8 inches (5.080 meters). Its angle of incidence was +1½° with no dihedral. The vertical fin had 0° offset. The empty weight of the XP-59A was 7,319 pounds (3,320 kilograms) and its maximum gross weight was 10,089 pounds (4,576 kilograms).

A cutaway display of a General Electric I-A turbojet engine. The compressor and turbine are on a single shaft (center). One of the combustion chambers is sectioned at the upper left. (National Museum of the United States Air Force)
A cutaway display of a General Electric I-A turbojet engine. The single-stage centrifugal compressor and single-stage axial-flow turbine are on a single shaft (center). One of the annular combustion chambers is sectioned at the upper left. (National Museum of the United States Air Force)

The experimental fighter was initially powered by two General Electric Type I-A centrifugal reverse-flow turbojet engines, serial numbers 170121 (left) and 170131 (right), each producing 1,250 pounds of thrust (5.561 kilonewtons) at 15,000 r.p.m. These were copies of the British Whittle W.2B engines. They were heavy, underpowered and unreliable.

Performance of the XP-59A was disappointing with a maximum speed of 350 miles per hour (563 kilometers per hour) at Sea Level and 389 miles per hour (626 kilometers per hour) at 35,160 feet (10,717 meters), significantly slower than many piston-engined fighters.

Three XP-59A prototypes and thirteen YP-59A preproduction airplanes were built. The P-59 was ordered into production and Bell Aircraft Corporation built thirty P-59A and twenty P-59B fighters. These were armed with one M4 37mm autocannon with 44 rounds of ammunition and three Browning AN-M2 .50-caliber machine guns with 200 rounds per gun.

Although a YP-59A had set an unofficial altitude record of 47,600 feet (14,508 meters), the Airacomet was so outclassed by standard production fighters that no more were ordered.

Lawrence D. ("Larry") Bell with his XP-59A Airacomet at Muroc Dry Lake. (Robert F. Dorr Collection)
Lawrence D. Bell with his XP-59A Airacomet at Muroc Dry Lake. (Robert F. Dorr Collection)

The race for a jet engine-powered fighter had been ongoing for several years, and the United States’ XP-59A was trailing behind. The first jet airplane, the Heinkel He 178, had made its first flight in Germany three years earlier, on 27 August 1939, though it was a proof-of-concept article, not an operational military aircraft. In the United Kingdom, the Gloster E/28.39, also a proof-of-concept aircraft, though more advanced than the Heinkel, made its first flight, 15 May 1941. The world’s first operational jet fighter, the Messerschmitt Me 262, made its first flight on 18 July 1942. It was nearly two years before production Me 262s entered combat, but they were devastating against bomber formations. The Gloster Meteor, the Allies’ first jet fighter, first flew 5 March 1943, and deliveries to fighter squadrons began in July 1944. The de Havilland DH.100 Vampire made its first flight 20 September 1943, but it did not become operational until after the end of World War II.

The XP-59A flew nearly five months before its British cousin, but would not be assigned to an operational squadron, the 445th Fighter Squadron, 412th Fighter Group, until June 1945.

The first American military jet aircraft, Bell XP-59A Airacomet 42-108784, was preserved by the Army at Muroc, and the engines at Wright Field, Ohio. In 1978, these were given to the Smithsonian Institution National Air and Space Museum where the prototype was later restored and placed on display.g9

The first American jet-powered aircraft, Bell XP-59A Airacomet 42-108784 on display at the National Air and Space Museum. (NASM)

© 2018, Bryan R. Swopes

27 September 1956

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Captain Milburn G. Apt, U.S. Air Force, with a Bell X-2. (U.S. Air Force)
Captain Milburn Grant Apt, United States Air Force, with a Bell X-2. (U. S. Air Force)

27 September 1956: Captain Milburn G. (“Mel”) Apt, United States Air Force, was an experimental test pilot assigned to the Air Force Flight Test Center at Edwards Air Force Base, California. After Frank Everest and Iven Kincheloe had made twelve powered flights in the Bell X-2 supersonic research aircraft, Mel Apt was the next test pilot to fly it.

The X-2 was a joint project of the U.S. Air Force and NACA (the National Advisory Committee on Aeronautics, the predecessor of NASA). The rocketplane was designed and built by Bell Aircraft Corporation of Buffalo, New York, to explore supersonic flight at speeds beyond the capabilities of the earlier Bell X-1 and Douglas D-558-II Skyrocket.

In addition to the aerodynamic effects of speeds in the Mach 2.0–Mach 3.0 range, engineers knew that the high temperatures created by aerodynamic friction would be a problem, so the aircraft was built from stainless steel and K-Monel, a copper-nickel alloy.

The Bell Aircraft Corporation X-2 was 37 feet, 10 inches (11.532 meters) long with a wingspan of 32 feet, 3 inches (9.830 meters) and height of 11 feet, 10 inches (3.607 meters). Its empty weight was 12,375 pounds (5,613 kilograms) and loaded weight was 24,910 pounds (11,299 kilograms).

Bell X-2 46-675 on its transportation dolly at Edwards Air Force Base, California, 1952. (NASA)
The second of two Bell X-2 supersonic research rocketplanes, 46-675, on its transportation dolly at Edwards Air Force Base, California, 1952. On 12 May 1953 this X-2 exploded during a captive test flight, killing Bell’s test pilot Jean L. “Skip” Ziegler. (NASA)

The X-2 was powered by a throttleable two-chamber Curtiss-Wright XLR25-CW-1 rocket engine that produced 2,500–15,000 pounds of thrust (11.12–66.72 kilonewtons)

Rather than use its limited fuel capacity to take off and climb to altitude, the X-2 was dropped from a modified heavy bomber as had been the earlier rocketplanes. A four-engine Boeing B-50D-95-BO Superfortress bomber, serial number 48-096, was modified as the drop ship and redesignated EB-50D.

The launch altitude was 30,000 feet (9,144 meters). After the fuel was exhausted, the X-2 glided to a touchdown on Rogers Dry Lake at Edwards Air Force Base.

Bell X-2 46-674 after drop from Boeing EB-50D Superfortress 48-096. (U.S. Air Force)
Bell X-2 46-674 after drop from Boeing EB-50D Superfortress 48-096. (U.S. Air Force)

With Mel Apt in the cockpit on his first rocketplane flight, the B-50 carried the X-2 to 31,800 feet (9,693 meters). After it was dropped from the bomber, Apt ignited the rocket engine and began to accelerate. He passed Mach 1 at 44,000 feet (13,411 meters) and continued to climb. Apt flew an “extraordinarily precise profile” to reach 72,200 feet (22,007 meters) where he put the X-2 into a dive. The rocket engine burned 12.5 seconds longer than planned, and at 65,589 feet (19,992 meters) the X-2 reached Mach 3.196 (2,094 miles per hour, 3,377 kilometers per hour).

Milburn Apt was the first pilot to exceed Mach 3. He was The Fastest Man Alive.

Bell X-2 46-674 in flight over Southern California, 1955–56. Note the supersonic diamond-shaped shock waves in the rocket engine's exhaust. (Bell aircraft Corporation)
Bell X-2 46-674 in flight over Southern California, 1955–56. Note the supersonic diamond-shaped shock waves in the rocket engine’s exhaust. (Bell Aircraft Corporation)

It was known that the X-2 could be unstable in high speed maneuvers. The flight plan called for Apt to slow to Mach 2.4 before beginning a gradual turn back toward Rogers Dry Lake where he was to land, but he began the turn while still at Mach 3. Twenty seconds after engine burn out, the X-2 began to oscillate in all axes and departed controlled flight. His last radio transmission was, “There she goes.” ¹

Mel Apt was subjected to acceleration forces of ± 6 Gs. It is believed that he was momentarily unconscious. Out of control, the X-2 fell through 40,000 feet (12,192 meters) in an inverted spin. Apt initiated the escape capsule separation, in which the entire nose of the X-2 was released from the airframe. It pitched down violently and Mel Apt was knocked unconscious again. He regained consciousness a second time and tried to parachute from the escape capsule, but was still inside when it hit the desert floor at several hundred miles per hour. Mel Apt was killed instantly.

Since 1950, Milburn G. Apt was the thirteenth test pilot killed at Edwards Air Force Base.

Wreckage of the Bell X-2, 46-674. (U.S. Air Force)
Wreckage of the Bell X-2, 46-674, in the Kramer Hills, east of Edwards Air Force Base. (U.S. Air Force)
Wreckage of the Bell X-2, 46-674. (NASM 9A08208)

Milburn Grant Apt was born at Buffalo, Kansas, 8 April 1924. He was the third child of Oley Glen Apt, a farmer, and Ada Willoughby Apt.

“Mel” Apt enlisted as a private in the Air Corps Enlisted Reserve, United States Army, 9 November 1942. On 23 June 1943, Private Apt was appointed an Aviation Cadet. After completing flight training, Cadet Apt was commissioned a Second Lieutenant, Army of the United States (A.U.S.). He was promoted to First Lieutenant, A.U.S., 4 September 1945. Apt was released from active duty on 11 August 1946. On 10 October 1947, he was reclassified as a Second Lieutenant, Air Corps, United States Army, with date of rank 8 April 1945.

In February 1950, Lieutenant Apt, then stationed at Williams Air Force Base, Arizona, married Miss Faye Lorrie Baker of Phoenix. They would have two children.

Mel Apt earned a Bachelor of Science degree from the University of Kansas, Lawrence, Kansas, in 1951, and a second bachelor’s degree in aeronautical engineering from the Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio. He then attended the U.S. Air Force Experimental Test Pilot School at Edwards Air Force Base, California, graduating in September 1954. Apt was assigned to the Fighter Operations Branch, Air Force Flight Test Center, as a test pilot.

On 22 December 1954, Captain Apt was flying a chase plane during a test at Edwards. The test aircraft crash-landed on the dry lake and caught fire with its pilot trapped inside. Mel Apt, with his bare hands, rescued the other test pilot, saving his life. For this courageous act, he was awarded the Soldier’s Medal.

Captain Apt was posthumously awarded the Distinguished Flying Cross for his flight in the X-2. The medal was presented to his widow in a ceremony at Edwards in March 1957.

Captain Milburn Grant Apt, United States Air Force, was 32 years old at the time of his death. His remains were buried at the Buffalo Cemetery, Buffalo, Kansas.

Captain Iven Carl Kincheloe and Captain Milburn Grant Apt (seated in cockpit) with the Bell X-2 at Edwards Air Force Base, 1956. (Jet Pilot Overseas)

¹ Recommended: Coupling Dynamics in Aircraft: A Historical Perspective, by Richard E. Day, Dryden Flight Research Center, Edwards AFB, California NASA Special Publications 532, 1997.

© 2018, Bryan R. Swopes