The Aerobee rocket was one of the United States' most produced and productive sounding rockets. Developed by the Aerojet Corporation, the Aerobee was designed to combine the altitude and launching capability of the V-2 with the cost effectiveness and mass production of the WAC Corporal. More than 1000 Aerobees were launched between 1947 and 1985, returning vast amounts of astronomical, physical, aeronomical, and biomedical data.
Development
Research using V-2 rockets after World War II produced valuable results concerning the nature of cosmic rays, the solar spectrum, and the distribution of atmospheric ozone. However, the limited supply and the expense of assembling and firing the V-2 rockets, as well as the small payload capacity of the first purpose-built sounding rocket, the WAC Corporal, created demand for a low cost sounding rocket to be used for scientific research. An Applied Physics Laboratory (APL) effort led by James Van Allen led to a contract presented 17 May 1946 by the Naval Research Laboratory (NRL) to Aerojet, at the time a producer of WAC Corporal rockets, for the procurement of 20 liquid-fueled sounding rockets capable of carrying a payload to an altitude of . 15 of the new rockets would be allocated to APL, and 5 to NRL. Aerojet was to be the prime contractor while Douglas Aircraft, also a producer of WAC Corporals, would provide aerodynamic engineering and take on some of the production.
The Aerojet designation for the new rocket was "Aerobee", a contraction of Aerojet, manufacturer of the engine, and Bumblebee, a Navy guided missile program. It was a single-stage, liquid-fueled, fin-stabilized rocket, using a solid-propellant rocket motor as a booster. This booster was jettisoned after 2.5 seconds of operation. The nose cone containing the telemetry transmitter and the scientific payload was recoverable and returned to earth on a parachute. As with its progenitor, the WAC Corporal, the Aerobee required a tall launch tower to provide the necessary stability until the relatively slowly accelerating rocket gained enough speed for its fins to be effective in controlling attitude. Launch towers were adjustable in inclination and azimuth to compensate for wind.
On 25 September 1947, a dummy Aerobee attached to a live engine was launched from White Sands Missile Range, New Mexico for flight testing. This was followed (after two more dummy tests in October) by the first complete Aerobee launch on 24 November. The flight was terminated after 35 seconds when the rocket's tail began yawing back and forth. This Aerobee was the first rocket fired by the US Navy at White Sands and the subject of the first comprehensive missile range safety program.
The next Aerobee launch, on 5 March 1948, was a complete success, achieving an altitude of and breaching the boundary of space (as defined by the World Air Sports Federation).
Operational history
Early launches
The original Aerobee design was designated RTV-N-8 by the Navy and XASR-1 by Aerojet and the Army. This rocket was powered by the XASR-1, a version of the 21AL-2600 engine also used in the Nike Ajax.
The XASR-1 engine was superseded by the XASR-2, which used helium for fuel tank pressurization instead of compressed air. First flying in late 1949, Aerobees using the new engine were designated RTV-N-10(a) by the Navy and RTV-A-1 by the Air Force. Variants on this design employed by the Air Force included the RTV-A-1a, which used an Aerojet AJ10-25 sustainer with of thrust, but with a shorter duration; the RTV-A-1c, identical but without a solid rocket booster; the RTV-A-1b, using the XASR-1 engine, but with chemical pressurization; and the RTV-A-1d, using the engine of the −1a, with chemical pressurization, and launched without booster.
The Navy also evolved their XASR-2 Aerobees. The RTV-N-10b used a variant of the −10a's engine with a higher specific impulse; the RTV-N-10c was a production variant of the −10b. The USAF fielded a production version of the RTV-N-10b, which did not get an official designation.
On 2 December 1949, the Air Force launched its first Aerobee from Holloman AFB Launch Complex A. Though the rocket flew to nearly in altitude and took the first color motion-pictures of the Earth from space, the payload was lost and not recovered until 13 July 1950, by which point the film (as well as x-ray emulsions that has also been carried aboard) were unsalvageable. This inauspicious beginning was followed by 32 more Aerobee flights, most of which were successful, including the first successful flight of a monkey, on 18 April 1951.