Bell X-2

The Bell X -2 Star Buster was a U.S. experimental aircraft, which was used to investigate flight characteristics in the speed range of Mach 2-3. It was a rocket-powered all-metal low-wing monoplane. Supporting and tail were performed in contrast to the direct predecessor, the Bell X -1, swept. Instead of an ejection seat a ejectable nose capsule was installed. For weight reasons for not using a chassis, instead it was landing skids.


One of the problems in attempting to achieve Mach 3, is to ensure a sufficient stability, and control of the aircraft. In addition from about Mach 2.6, the so-called heat wall, in which the aircraft is aerodynamically heated to the extent that conventional metals can not be used anymore. For the study of these extreme conditions, the Bell X -2 was constructed of stainless steel and a copper -nickel alloy and equipped with swept wings and a XLR25 rocket engine that could develop 11-67 kN thrust in two combustion chambers. The X-2 finally was the first aircraft that flew to the edge of the atmosphere at the edge of space.

Service history

On 27 June 1952, the test pilot Jean "Skip" Ziegler led (? ) Has a first gliding flight without using the engine from. The X -2 was hung out to start with a converted B-50 bomber and brought from Edwards Air Force Base on application level. However, this first X-2 was lost at a later towed flight in 1953 by an explosion that took the lives of Ziegler.

Lt.. Col. Frank K. " Pete " Everest led to a second X-2 on 18 November 1955 the first powered flight by. In his ninth and final flight in late July of the following year he exhibited at Mach 2.87 ( 3050 km / h ) to a new unofficial speed record. The X - 2 is not fulfilled so that the expectations placed on them, but without problems. Everest reported that the aircraft at high speeds hardly respond to the control system. Moreover, turned in simulations and wind tunnel tests together with the data from its test flights out that the aircraft would have serious stability problems when it reaches Mach 3.

Some young test pilot, Captain Iven C. Kincheloe and Captain Milburn G. " Mel" Apt, the task was intended for, to conduct the experiments on. On September 7, 1956 by Kincheloe was the first to pilot the 100,000 ft ( 30,500 m) altitude mark when he up to an altitude of 126,200 ft with the X -2 ( 38 466 m ) increased.

Just 20 days later, on the morning of September 27, Mel Apt started out for his first rocket flight of the B-50. His mission was to follow a trajectory that made ​​it possible to implement the available energy of the entrained fuel in a maximum speed. Due to the problems identified respecting any rapid control movements should be avoided beyond Mach 2.7. He could by an extremely tight- preserved trajectory that day exceed the first man to Mach 3, and ultimately in 19,960 m Mach 3.2 reach ( 3370 km / h ). Until then, the flight was smooth, but for unknown reasons, he attempted shortly after reaching the maximum speed of the aircraft to turn sideways while he was still flying well above Mach 3. The cause is a slow -reacting instrument display, which has shown a lower than actual speed suspected. Maybe feared Apt also that he came off too far from the runway at the Rogers Dry Lake. The X-2 got it in a flat spin as it also almost 3 years ago Chuck Yeager had to experience in the X -1A. Unlike Yaeger however Apt could not bring his aircraft back under control, and the X -2 was lost with him.

This event led to discontinuation of the program, even before the National Advisory Committee for Aeronautics could make more detailed studies with the X -2. Nevertheless, they provided valuable research data on high-speed aerodynamics and extreme altitude flight conditions. The further exploration of the high- speed range was continued only with the North American X-15.

Flight test program

Two aircraft resulted in the period 27 June 1952 to September 27, 1956 a total of 20 flights.

  • 46-674, 7 gliding, 10 driven Flights
  • 46-675, 3 driven Flights


  • Crew: 1
  • Length: 11.5 m (37 ft 10 in )
  • Wingspan: 9.8 m (32 ft 3 in )
  • Height: 3.6 m (11 ft 10 in )
  • Empty weight: 5600 kg ( 12,375 lb)
  • Maximum takeoff weight: 11,300 kg ( 24,910 lb)
  • Engine: Curtiss -Wright XLR25 rocket engine 15,000 lbf (67 kN) of static thrust.


  • Maximum speed: Mach 3.196 ( 3370 km / h )
  • Ceiling: 38 466 m ( 126,200 ft)


  • American X - Vehicles: An Inventory X-1 to X-50, SP - 2000-4531 - June 2003; NASA Monograph online PDF ( 1.10 MB )

Pictures of Bell X-2