NACA 135, a North American Aviation F-86A-1-NA Sabre, 47-609, is lowered into the 40′ x 80′ Full Scale Wind Tunnel at NACA’s Ames Aeronautical Laboratory, circa January 1954. (NASA)
During January 1954, a North American Aviation F-86A-1-NA Sabre, 47-609 (NAA s/n 151-38433) was tested in the National Advisory Committee for Aeronautics (NACA) Ames Aeronautical Laboratory Full Scale Wind Tunnel at Moffett Field, California.
NACA 135 variable-stability test aircraft. (NASA)
47-609 had made its first flight 31 July 1948. It was retained by North American for testing. It was redesignated EF-86A, 3 March 1949.
On 10 April 1950, 47-609 was assigned to the NACA Ames Aeronautical Laboratory, designated NACA 135. The airplane was used for evaluation of flying qualities, stability and control, and performance. The Sabre was also used as a variable-stability test bed. It remained with NACA until 15 March 1956.
NACA 135 (F-86A-1-NA 47-609) in the Ames Aeronautical Laboratory 40′ x 80′ Full Scale Wind Tunnel, circa January 1954. (NASA)
Jack Valentine Woolams, Chief Experimental Test Pilot, Bell Aircraft Corporation. (John Trudell/Ancestry)
25 January 1946:¹ Near Pinecastle Army Airfield in central Florida, Bell Aircraft Corporation Senior Experimental Test Pilot Jack Woolams made the first unpowered glide flight of the XS-1 supersonic research rocketplane, 46-062.
46-062 was the first of three XS-1 rocketplanes built by Bell for the U.S. Army Air Corps and the National Advisory Committee for Aeronautics (NACA) to explore flight at speeds at and beyond Mach 1, the speed of sound. The airplane had been rolled out of Bell’s plant at Buffalo, New York, on 27 December 1945. The rocket engine, which was being developed by Reaction Motors, Inc., at Franklin Lakes, New Jersey, was not ready, so the experimental aircraft was carrying ballast in its place for the initial flight tests.
Jack Woolams with the second Bell XS-1, 46-063. (Niagara Aerospace Museum)
The XS-1 was to be air-dropped from altitude by a modified heavy bomber so that its fuel could be used for acceleration to high speeds at altitude, rather than expended climbing from the surface. Bell manufactured B-29B Superfortresses at its Atlanta, Georgia, plant and was therefore very familiar with its capabilities. A B-29, 45-21800, was selected as the drop ship and modified to carry the rocketplane in its bomb bay.
Boeing B-29-96-BW Superfortress 45-21800 carries a Bell XS-1 rocketplane. (Bell Aircraft Museum)
Pinecastle Army Airfield was chosen as the site of the first flight tests because it had a 10,000 foot (3,048 meter) runway and was fairly remote. There was an adjacent bombing range and the base was a proving ground for such aircraft as the Consolidated B-32 Dominator. (Today, Pinecastle A.A.F. is known as Orlando International Airport, MCO.)
Bell XS-1 46-062 was placed in a pit at Pinecastle A.A.F. so that the B-29 drop ship in the background could be positioned over it. (NASA)
The B-29 carrying the XS-1 took off from Pinecastle at 11:15 a.m., and began its climb to altitude. Woolams was in the forward crew compartment. As the bomber reached approximately 10,000 feet (3,048 meters), he entered the bomb bay and climbed down into the cockpit of the research aircraft. At the drop altitude, the B-29 was flying at 180 miles per hour (290 kilometers per hour) with the inboard propellers feathered and flaps lowered to 20°.
The XS-1 dropped away smoothly. Woolams flew the rocketplane to a maximum 275 miles per hour (443 kilometers per hour), indicated air speed, during this first glide test. He described the rocketplane as, “solid as a rock, experiencing absolutely no vibration or noise. At the same time, it felt as light as a feather during maneuvers due to the lightness, effectiveness and nice balance between the controls.” Woolams described the visibility from the cockpit as “not good, but adequate.”
The duration of the first glide flight was about ten minutes. Woolams misjudged his approach to Pinecastle and landed slightly short of the runway, on the grass shoulder, but the XS-1 was not damaged.
The conclusion of Woolams’ flight report is highly complementary of the experimental airplane:
11. Of all the airplanes the writer has flown, only the XP-77 and the Heinkel 162 compare with the XS-1 for maneuverability, control relationship, response to control movements, and lightness of control forces. Although these impressions were rather hastily gained during a flight which lasted only 10 minutes, it is the writer’s opinion that due to these factors and adding to them the security which the pilot feels due to the ruggedness, noiselessness, and smoothness of response of this airplane, it is the most delightful to fly of them all.
—PILOT’S REPORT, Flight 1, by Jack Woolams
Jack Woolams made ten glide flights with 46-062, evaluating its handling characteristics and stability. The aircraft was returned to Bell to have the rocket engine installed, and it was then sent to Muroc Army Airfield in the high desert of southern California for powered flight tests. (Muroc A.A.F. was renamed Edwards Air Force Base in 1949.)
Bell XS-1 46-062 was later named Glamorous Glennis by its military test pilot, Captain Charles E. Yeager, U.S. Army Air Corps. On 14 October 1947, Chuck Yeager flew it to Mach 1.06 at 13,115 meters (43,030 feet). Today the experimental aircraft is on display at the Smithsonian Institution National Air and Space Museum.
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.
An X-1 under construction at the Bell Aircraft Corporation plant, Buffalo, New York. (Bell Aircraft Corporation)
The X-1 has an ogive nose, similar to the shape of a .50-caliber machine gun 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).
46-062 was built with a thin 8% aspect ratio wing, while 46-063 had a 10% thick wing. The wings were tapered, having a root chord of 6 feet, 2.2 inches (1.885 meters) and tip chord of 3 feet, 1.1 inches (0.942 meters), resulting in a total area of 130 square feet (12.1 square meters). The wings have an angle of incidence of 2.5° with -1.0° twist and 0° dihedral. The leading edges are swept aft 5.05°.
The horizontal stabilizer has a span of 11.4 feet (3.475 meters) and an area of 26.0 square feet (2.42 square meters). 062’s stabilizer has an aspect ratio of 6%, and 063’s, 5%.
The fuselage cross section is circular. At its widest point, the diameter of the X-1 fuselage is 4 feet, 7 inches (1.397 meters).
46-062 had an 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.
Front view of a Bell XS-1 supersonic research rocketplane at the Bell Aircraft plant, Buffalo, New York. (Bell Aircraft Museum)
The X-1 was powered by a four-chamber Reaction Motors, Inc., 6000C4 (XLR11-RM-3 ) rocket engine which produced 6,000 pounds of thrust (26,689 Newtons). This engine burned a 75/25 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 was pressurized by nitrogen at 1,500 pounds per square inch (103.4 Bar).
The X-1 was usually dropped from the 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).
Bell X-1 46-062 on the dry lake bed at Muroc Army Airfield, circa 1947. (NASM)
The X-1 had a minimum landing speed of 135 miles per hour (217 kilometers per hour) using 60% flaps.
There were 157 flights with the three X-1 rocket planes. The number one ship, 46-062, 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 at the National Air and Space Museum, Washington, D.C. (NASM)
Jack Valentine Woolams was born on Valentine’s Day, 14 February 1917, at San Francisco, California. He was the second of three children of Leonard Alfred Woolams, a corporate comptroller, and Elsa Mathilda Cellarius Woolams. He grew up in San Rafael, California, and graduated from Tamalpais School in 1935.
Jack Woolams, 1941
After two years of study at The University of Chicago, in 1937 Woolams entered the Air Corps, U.S. Army, as an aviation cadet. He trained as a pilot at Kelly Field, San Antonio, Texas. On graduation, 16 June 1938, he was discharged as an aviation cadet and commissioned as a second lieutenant, Air Reserve. He was assigned to Barksdale Army Air Field, Louisiana, where he flew the Boeing P-26 and Curtiss P-36 Hawk.
On 10 February 1939, Lieutenant Woolams was one of three Air Corps officers thrown into the waters of Cross Lake, near Shreveport, Louisiana, when the boat, owned by Woolams, capsized in 4 foot (1.2 meters) waves. Woolams and Lieutenant J.E. Bowen were rescued after 4 hours in the water, but the third man, Lieutenant Wilbur D. Camp, died of exposure.
Lieutenant Woolams transferred from active duty to inactive reserve status in September 1939 in order to pursue his college education at The University of Chicago, where he was a member of the Alpha Delta Phi (ΑΔΦ) fraternity. While at U. of C., he played on the university’s football and baseball teams, and was a member of the dramatic society. Woolams graduated 18 July 1941 with a Bachelor of Arts (A.B.) degree in Economics.
Mr. and Mrs. Jack V. Woolams, 16 June1941. (Unattributed)
Jack Woolams married Miss Mary Margaret Mayer at the bride’s home in Riverside, Illinois, 16 June 1941. They would have three children. Miss Mayer was also a 1941 graduate from the University of Chicago. She had been Woolams’ student in the Civilian Pilot Training Program.
Woolams became a production test pilot for the Bell Aircraft Corporation at Buffalo, New York. He tested newly-built Bell P-39 Airacobra fighters. As he became more experienced, he transitioned to experimental testing with the P-39, P-63 King Cobra, and the jet-powered P-59 Airacomet.
Jack Valentine Woolams, Chief Experimental Test Pilot, Bell Aircraft Corporation, circa 1946. (Niagara Aerospace Museum)
On 28 September 1942, Jack Woolams flew a highly-modified Bell P-39D-1-BE Airacobra, 41-38287, from March Field, near Riverside, California, to Bolling Field, Washington, D.C., non-stop. The duration of the flight was approximately 11 hours. The modifications were intended to allow P-39s to be flown across the Pacific Ocean to Hawaii and on to the Soviet Union for delivery under Lend Lease.
During the summer of 1943, Woolams flew the first Bell YP-59A Airacomet, 42-108771, to an altitude of 47,600 feet (14,508 meters) near Muroc Army Air Field in California.
On 5 January 1945, Woolams was forced to bail out of a Bell P-59A-1-BE, 44-22616. He suffered a deep laceration to his head as he left the airplane. He lost his flight boots when the parachute opened, and on landing, had to walk barefoot through knee-deep snow for several miles to reach a farm house. The deep snow prevented the company’s ambulance from getting to Woolams. Bell Aircraft president Lawrence D. Bell sent the company’s second prototype Bell Model 30 helicopter, NX41868, flown by test pilot Floyd Carlson, to transport a doctor, J.A. Marriott, M.D., to the location. Another Bell test pilot, Joe Mashman, circled overhead in a P-63 King Cobra to provide a communications link. Later in the day, an ambulance was able to get through the snow to take Woolams to a hospital.
Wreckage of Bell P-59A-1-BE Airacomet 44-22616. Jack Woolams bailed out of this airplane 5 January 1945. (Niagara Aerospace Museum)
Woolams was scheduled to make the first powered flight of the XS-1 during October 1946.
Jack Woolams was killed Friday, 30 August 1946, when his red Thompson Trophy racer, Cobra I, a modified 2,000-horsepower Bell P-39Q Airacobra, crashed into Lake Ontario at over 400 miles per hour. His body was recovered by the U.S. Coast Guard four days later.
Bell Aircraft Corporation experimental test pilots Jack Woolams and Tex Johnston with their modified Bell P-39Q Airacobras, Cobra I and Cobra II. (Niagara Aerospace Museum)
¹ This article was originally dated 19 January 1946. There were known discrepancies as to the date of the first flight from various reliable sources. Recently discovered test flight reports, provided to TDiA by Mr. Roy T. Lindberg, Historian of the Niagara Aerospace Museum, Niagara Falls, New York, have confirmed that the date of the first flight was actually 25 January 1946. The article has been been revised accordingly, as well as to incorporate new information from these reports.
TDiA is indebted to Mr. Lindberg for providing this and other documentation.
North American Aviation XP-51 Mustang 41-038 at Langley Field, Virginia, 29 December 1941. (NASA)
29 December 1941: The first North American Aviation XP-51 fighter prototype, Air Corps serial number 41-038, arrived at the National Advisory Committee for Aeronautics Langley Memorial Aeronautical Laboratory, Langley Field, Hampton, Virginia, for flight testing. This airplane was the fourth production Royal Air Force Mustang Mk.I, North American serial number 73-3101.
The test program resulted in an improved aileron design which significantly improved the Mustang’s maneuverability. The new aileron was used on all production models.
North American Aviation XP-51 41-038 at the NACA Langley Memorial Aeronautical Laboratory. (NASA)
41-038 was returned to Wright Field on 2 November 1942. The second XP-51, 41-039, arrived at Langley in March 1943 for continued testing.
The Mustang Mk.I (NAA Model NA-73) was a single-place, single-engine fighter of all metal construction. It was 32 feet, 3 inches (9.830 meters) long with a wingspan of 37 feet, ½-inch (11.290 meters) and overall height of 12 feet, 2½ inches (3.719 meters). The airplane’s empty weight was 6,280 pounds (25,848.6 kilograms) and loaded weight was 8,400 pounds (3,810.2 kilograms).
North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory, right profile. (NASA)
The Mustang Mk.I/XP-51 was powered by a liquid-cooled, supercharged 1,710.60-cubic-inch-displacement (28.032 liter) Allison Engineering Company V-1710-F3R (V-1710-39) single overhead cam 60° V-12 engine, with a compression ratio of 6.65:1 and a single-stage, single-speed supercharger. This was a right-hand tractor engine (the V-1710 was built in both right-hand and left-hand configurations) which drove a 10 foot, 6 inch (3.200 meter) diameter, three-bladed, Curtiss Electric constant-speed propeller through a 2.00:1 gear reduction.
The V-1710-39 had a Normal Power rating of 880 horsepower at 2,600 r.p.m. at Sea Level; Take Off Power rating of 1,150 horsepower at 3,000 r.p.m. at Sea Level, with 44.5 inches of manifold pressure (1.51 Bar), 5 minute limit; and a War Emergency Power rating of 1,490 horsepower at 3,000 r.p.m., with 56 inches of manifold pressure (1.90 Bar). The V-1710-F3R was 3 feet, ¾ inches (0.934 meters) high, 2 feet, 5-9/32 inches (0.744 meters) wide and 7 feet, 1-5/8 inches (2.175 meters) long. It had a dry weight of 1,310 pounds (594 kilograms).
North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory. (NASA)
The XP-51 tested at Wright Field had a maximum speed of 382.0 miles per hour (614.8 kilometers per hour) at 13,000 feet (3,962 meters) at wide open throttle, and cruise speed of 300 miles per hour (483 kilometers per hour).
Below 20,000 feet (6,096 meters), the Mustang was the fastest fighter in the world. The Mk.I was 30 m.p.h. (48 kilometers per hour) faster than its contemporary, the Curtiss P-40 Warhawk, though both used exactly the same engine. Below 15,000 feet (4,572 meters), the Mustang was also 30–35 m.p.h (48–56 km/h) faster than a Supermarine Spitfire, which was equipped with the more powerful Roll-Royce Merlin V-12.
The service ceiling was 30,800 feet (9,388 meters) and range was 750 miles (1,207 kilometers).
North American Aviation XP-51 41-038 at NACA Langley Memorial Aeronautical Laboratory, rear view. (NASA)
Armament consisted of two synchronized Browning AN-M2 .50-caliber machine guns mounted in the nose under the engine and firing through the propeller, and two more .50-caliber and four Browning .303 Mk.II machine guns in the wings.
North American Aviation XP-51 instrument panel. (U.S. Air Force)
Two Mustang Mk.Is, AG348 and AG354, were taken from the first RAF production order and sent to Wright Field for testing by the U.S. Army Air Corps. These airplanes, assigned Air Corps serial numbers 41-038 and 41-039, were designated XP-51. They would be developed into the legendary P-51 Mustang. In production from 1941 to 1945, a total of 16,766 Mustangs of all variants were built.
North American XP-51 41-038 was transferred to the Smithsonian Institution National Air and Space Museum. It was restored in 1976. It is now in the collection of the EAA AirVenture Museum, Oshkosh, Wisconsin. It has a current FAA registration number, N51NA.
North American Aviation XP-51 41-038 in the collection of the Experimental Aircraft Association AirVenture Museum, Oshkosh, Wisconsin. (EAA AirVenture Museum)
20 November 1953: At Edwards Air Force Base, California, NACA’s High Speed Flight Station research test pilot Albert Scott Crossfield, Jr., rode behind the flight crew of the Boeing P2B-1S Superfortress as it carried the Douglas Aircraft Company D-558-II Skyrocket supersonic research rocketplane to its launch altitude. As the four-engine bomber climbed through 18,000 feet (5,486 meters), Crossfield headed back to the bomb bay to enter the Skyrocket’s cockpit and prepare for his flight.
Douglas D-558-II Skyrocket Bu. No. 37974, NACA 144, on Rogers Dry Lake. (NASA)
The Douglas D-558-II was Phase II of a United States Navy/Douglas Aircraft Company/National Advisory Committee on Aeronautics joint research project exploring supersonic flight. It was a swept-wing airplane powered by a single Reaction Motors LR8-RM-6 four-chamber rocket engine. The Skyrocket was fueled with alcohol and liquid oxygen. The engine was rated at 6,000 pounds of thrust (26.69 kilonewtons) at Sea Level.
There were three Phase II aircraft. Originally, they were also equipped with a Westinghouse J34-W-40 turbojet engine which produced 3,000 pounds of thrust (13.35 kilonewtons). The Skyrockets took off from the surface of Rogers Dry Lake. Once the D-558-II reached altitude, the rocket engine was fired for the speed runs.
As higher speeds were required, the program shifted to an air launch from a B-29 (P2B-1S) drop ship. Without the need to climb to the test altitude, the Skyrocket’s fuel load was available for the high speed runs.
NACA 144. a Douglas D-558-II Skyrocket, Bu. No. 37974, on Rogers Dry Lake. (NASA)
The D-558-II was 42.0 feet (12.80 meters) long, with a wingspan of 25.0 feet (7.62 meters). The leading edge of the wing was swept at a 35° angle and the tail surfaces were swept to 40°. The aircraft weighed 9,421 pounds (4,273 kilograms) empty and had a maximum takeoff weight of 15,787 pounds (7,161 kilograms). It carried 378 gallons (1,431 liters) of water/ethyl alcohol and 345 gallons (1,306 liters) of liquid oxygen.
The mothership, NACA 137, was a Boeing Wichita B-29-95-BW Superfortress, U.S. Air Force serial number 45-21787. It was transferred to the U.S. Navy, redesignated P2B-1S and assigned Bureau of Aeronautics number 84029. Douglas Aircraft modified the bomber for its drop ship role at the El Segundo plant.
Douglas D-558-II Skyrocket, Bu. No. 37974, NACA 144, is dropped from the Boeing P2B-1S Superfortress, Bu. No. 84029, NACA 137. (NASA)
Going above the planned launch altitude, the Superfortress was placed in a slight dive to build to its maximum speed. At the bomber’s critical Mach number (Mcr), the Skyrocket was just above its stall speed. At 32,000 feet (9,754 meters), Crossfield and the Skyrocket were released. The rocketplane fell for about 400 feet (122 meters) before the rocket engine ignited and then it began to accelerate.
A Douglas D-558-II drops away from the Boeing Superfortress mother ship. (Der Spiegel/Schenectady Museum; Hall of Electrical History Foundation/CORBIS)
Crossfield climbed at a steep angle until he reached 72,000 feet (21,946 meters), and then leveled off. Now in level flight, the D-558-II continued to accelerate, quickly passing Mach 1, then Mach 1.5. Crossfield pushed the nose down and began a shallow dive. The Skyrocket, still under full power, built up speed. As it passed through 62,000 feet (18,998 meters) the Skyrocket reached its maximum speed, Mach 2.005, or 1,291 miles per hour (2,078 kilometers per hour).
Scott Crossfield and the Douglas D-558-II Skyrocket, with their support team: two North American F-86 Sabre chase planes and the Boeing P2B-1S Superfortress mothership, at the NACA High Speed Flight Station, Edwards Air Force Base, California, 1 January 1954. (NASA)
Scott Crossfield was the first pilot to fly an aircraft beyond Mach 2, twice the speed of sound. During his career as a test pilot, he flew the Douglas D-558-II, the Bell X-1, and North American X-15. He made 112 flights in rocket-powered aircraft, more than any other pilot.
Albert Scott Crossfield, Jr., Aeronautical Engineer and Test Pilot, 1921–2006. (Jet Pilot Overseas)
6 November 1958: NASA Research Test Pilot John B. (Jack) McKay made the final flight of the X-1 rocketplane program, which had begun twelve years earlier.
Bell X-1E 46-063 made its 26th and final flight after being dropped from a Boeing B-29 Superfortress over Edwards Air Force Base on a flight to test a new rocket fuel.
John B. McKay, NACA/NASA Research Test Pilot. (NASA)
When the aircraft was inspected after the flight, a crack was found in a structural bulkhead. A decision was made to retire the X-1E and the flight test program was ended.
The X-1E had been modified from the third XS-1, 46-063. It used a thinner wing and had an improved fuel system. The most obvious visible difference is the cockpit, which was changed to provide for an ejection seat. Hundreds of sensors were built into the aircraft’s surfaces to measure air pressure and temperature.
The Bell X-1E was 31 feet (9.449 meters) long, with a wingspan of 22 feet, 10 inches (6.960 meters). The rocketplane’s empty weight was 6,850 pounds (3,107 kilograms) and fully loaded, it weighed 14,750 pounds (6,690 kilograms). The rocketplane was powered by a Reaction Motors XLR11-RM-5 rocket engine which produced 6,000 pounds of thrust (26.689 kilonewtons). The engine burned ethyl alcohol and liquid oxygen. The X-1E carried enough propellants for 4 minutes, 45 seconds burn.
The Bell X-1E rocketplane being loaded into NACA 800, a Boeing B-29-96-BW Superfortress mothership, 45-21800, for another test flight. (NASA)
The early aircraft, the XS-1 (later redesignated X-1), which U.S. Air Force test pilot Charles E. (“Chuck”) Yeager flew faster than sound on 14 October 1947, were intended to explore flight in the high subsonic and low supersonic range. There were three X-1 rocketplanes. Yeager’s Glamorous Glennis was 46-062. The X-1D (which was destroyed in an accidental explosion after a single glide flight) and the X-1E were built to investigate the effects of frictional aerodynamic heating in the higher supersonic ranges from Mach 1 to Mach 2.
Bell X-1E 46-063 loaded aboard NACA 800, a Boeing B-29-96-BW Superfortress, 45-21800, circa 1955. (NASA)
The X-1E reached its fastest speed with NASA test pilot Joseph Albert Walker, at Mach 2.24 (1,450 miles per hour/2,334 kilometers per hour), 8 October 1957. Walker also flew it to its peak altitude, 70,046 feet (21,350 meters) on 14 May 1958.
NACA test pilot Joseph Albert Walker made 21 of the X-1E’s 26 flights. In this photograph, Joe Walker is wearing a David Clark Co. T-1 capstan-type partial-pressure suit with a K-1 helmet for protection at high altitudes. (NASA)
There were a total of 236 flights made by the X-1, X-1A, X-1B, X-1D and X-1E. The X-1 program was sponsored by the National Advisory Committee on Aeronautics, NACA, which became the National Aeronautics and Space Administration, NASA, on 29 June 1958.