TheApollo11Channel's video: Neil Armstrong - Lunar Landing Research Vehicle LLRV Test Flight - 1969

The Bell Aerosystems Lunar Landing Research Vehicle (LLRV) was an Apollo Project era program to build a simulator for the Moon landings. The LLRVs, humorously referred to as "flying bedsteads" was a vertical take-off and landing (VTOL) aircraft. Apollo 11 astronaut, Neil Armstrong -- first human to step onto the Moon's surface -- said the mission would not have been successful without the type of simulation that resulted from the LLRV's. The lunar lander, called a Lunar Excursion Module, or Lunar Module (LM), was designed for vertical landing and takeoff, and was able to briefly hover and fly horizontally before landing. At first glance it seemed that a helicopter could be used to simulate flying the LM, but early test flights proved that it was not even close. Helicopters, or any vertical takeoff and landing (VTOL) aircraft, are subject to the influences of winds, air temperature, and the Earth's gravity. In order to simulate flying near the Moon, the flight vehicle had to automatically nullify the effects of nature so it would behave as if it were operating in a vacuum, and it had to respond as if it were subject to the much lighter lunar gravity.