The Lunar Landing Research Vehicle (LLRV), built by Bell Aerosystems, was an Apollo Project era program to build a VTOL simulator for the Moon landings. The LLRVs were flown at what is now the NASA Dryden Flight Research Center, at Edwards Air Force Base, California, to study and analyze piloting techniques needed to fly and land the Apollo Lunar Module in the moon's low gravity environment.
The LLRV was powered by a General Electric CF700-2V turbofan engine with a thrust of 4,200 lb (19 kN), mounted vertically in a gimbal. It was throttled to provide thrust equivalent to 5/6th of the vehicle’s weight, thus simulating the moon’s 1/6 gravitational pull. Hydrogen peroxide rockets then simulated the behavior of a lunar lander's controls during landing.
Two LLRVs were built, which led to three Lunar Landing Training Vehicles (LLTVs) used by Apollo astronauts at what is now Johnson Space Center in Houston, Texas. Neil Armstrong was flying LLRV-1 on May 6, 1968 when it went out of control. He ejected safely and the vehicle crashed. Later, two of the LLTVs were also crashed, with pilots also safely ejecting.
By Mike Hirschberg