Bell X-1: Difference between revisions

For the article about the Irish band, see Bell X1.

The Bell X-1, originally XS-1 was the first aircraft to exceed the speed of sound in controlled, level flight. It was the first of the so called X-planes, a series of aircraft designated for testing of new technologies and usually kept highly secret.

Many believe the X-1 was heavily based on the British designed Miles M.52 jet. The Miles M.52 was cancelled by the British government just months away from a test flight, and all technical data regarding it was transferred to Bell. The one critical piece of design transferred from the M.52 to the XS-1 was the all-moving tail, key to supersonic flight control. Later tests show that the Miles M.52 would probably have broken the sound barrier if allowed to fly.

Chalmers "Slick" Goodlin was the original test pilot for the second plane in the X-1 program. He made twenty-six successful flights in both of the X-1 aircraft from September 1946 until June 1947. Bell Aircraft's contract was terminated and was taken over by the United States Air Force.

On October 14, 1947, Captain Charles "Chuck" Yeager of the Air Force flew aircraft #46-062, which he had named 'Glamorous Glennis', after his wife. The rocket-powered aircraft was launched from the belly of a specially modified B-29 and glided to a landing on a runway. Aircraft #46-062 is the model currently on display in the main atrium of the National Air and Space Museum in Washington, DC, on the same side as the Spirit of St. Louis and SpaceShipOne.

The German pilot Hans Guido Mutke claimed to be the first person to break the sound barrier, on April 9, 1945 in a Messerschmitt Me 262, but this claim is disputed. The mysterious 702 mph Me-163B by Dittmar flight is wrapped in mystery and has no Mach number associated with it. Many also contend that George Welch broke the barrier on October 1, 1947 in his XP-86 Sabre during a dive, just two weeks before the X-1. Full confirmation of Welch's achievement is not available, although it is very likely that he exceeded Mach 1 more than once sometime in the October - November, 1947 period, and perhaps as early as October 1.

It should be noted that the intentions of the X-1 experiments were not to exceed the speed of sound in of itself, but to determine if, and then demonstrate that, controlled, sustained flight was possible at supersonic speeds. In the above claims, the sound barrier was supposedly breached by diving aircraft and it would be impossible there to determine if aerodynamic lift could be maintained at those speeds.

Later variants of the X-1 were built to test different aspects of supersonic flight; one of these, the X-1A, with Yeager at the controls, inadvertently demonstrated a very dangerous characteristic of fast (Mach 2-plus) supersonic flight: inertia coupling. Only Yeager's skills as an aviator prevented him from dying that day; later Mel Apt would die testing the Bell X-2 under similar circumstances.

History

X-1 at the Smithsonian

Beginning in 1946, two XS-1 (for "Experimental, Supersonic", later X-1) experimental research aircraft conducted pioneering tests at Muroc Army Air Field (now Edwards Air Force Base) in California to obtain flight data on conditions in the transonic speed range. These early tests culminated in the first piloted flight faster than Mach 1.0, the speed of sound. XS-1 flight number 50 is the first one where the X-1 recorded supersonic flight, at Mach 1.06 peak speed; however, Yeager and many other personnel record the possibility that Flight #49 (also with Yeager piloting), which reached a top recorded speed of Mach 0.997, may have in fact passed the Sound Barrier. (The measurements were not accurate to three significant figures and no sonic boom is recorded for that flight.)

XLR-11 rocket engine

The XS-1 was the first high-speed aircraft built purely for aviation research purposes. The model was never intended for production. She was designed largely in accordance with specifications provided by the National Advisory Committee for Aeronautics (NACA) (now NASA), paid for by the Army Air Forces, and built by Bell Aircraft Inc. The XS-1 #2 (serial number 46-063) was flight tested by the NACA to provide design data for later production high-performance aircraft.

The research techniques used in the X-1 program became the pattern for all subsequent X-craft projects. The NACA X-1 procedures and personnel also helped lay the foundation of America's space program in the 1960s. The X-1 project defined and solidified the post-war cooperative union between U.S. military needs, industrial capabilities, and research facilities. The flight data collected by the NACA in the X-1 tests then provided a basis for American aviation supremacy in the latter half of the 20th century.

As a result of the X-1's initial supersonic flight, the National Aviation Association voted its 1948 Collier Trophy to be shared by the three main participants in the program. Honored at the White House by President Truman were Larry Bell for Bell Aircraft, Captain Yeager for piloting the flights, and John Stack of NACA for the NACA contributions. Years later, Yeager reported that his father, a staunch Republican, refused to shake hands with President Truman (a Democrat).

Specifications (X-1)

Three view diagram

Three view diagram

General characteristics of Bell X-1

• Crew of Plane: 1
• Length of Plane: 30 ft 11 in (9.4 m)
• Wingspan of Plane: 28 ft 0 in (8.5 m)
• Height of Plane: 10 ft 10 in (3.3 m)
• Wing area of Plane: 130 ft² (12 m²)
• Empty: 7,000 lb (3,175 kg)
• Loaded: 12,225 lb (5,545 kg)
• Maximum takeoff: 12,250 lb (5,557 kg)
• Powerplant: Reaction Motors XLR-11-RM3 rocket engine, 6,000 lbf (26.7 kN) thrust

Performance

• Maximum speed: 957 mph (1,541 km·h^-1)
• Range: 5 minutes powered endurance
• Service ceiling: 71,900 ft (21,900 m)
• Wing loading: 94 lb/ft² (463 kg·m^-1)
• Thrust/weight: 0.49

See also

• X-plane

References

TV program: Modern Marvels - Breaking the sound barrier, 2003

External links

• Bell X-1 Milestones of Flight
• NASA's History of the X-1
• Goodlin's NASA biography
• American X-Vehicles: An Inventory X-1 to X-50, SP-2000-4531 - June 2003; NASA online PDF Monograph
• Photo of Glamorous Glennis on display at the National Air and Space Museum in Washington, DC.
• Yeager's personal website

See also

• List of experimental aircraft
• List of rocket planes
• List of X-1 flights - list of XS-1 pilots and flights.
• List of X-1A flights - list of X-1A pilots and flights.
• List of X-1B flights - list of X-1B pilots and flights.
• List of X-1D flights - list of X-1D pilots and flights.
• List of X-1E flights - list of X-1E pilots and flights.
• Mach number
• Miles M.52 - An earlier British design which may have substantially influenced the development of the X-1