Before the Apollo astronauts landed on the moon, they first had to practice on Earth. A colloquium at NASA Armstrong Flight Research Center on Oct. 29 marked the 50th anniversary of the first flight of a most unusual vehicle that was used to train the first humans to visit another world – the Lunar Landing Research Vehicle, or LLRV. Guest speakers included former project manager Gene Matranga, engineer Wayne Ottinger, pilot Donald Mallick, and Rocket Shop supervisor Dave Stoddard. Other original LLRV team members present included Glenn Angle and Adam Mello.

In the early 1960s, NASA studied several techniques for simulating descent to the lunar surface. Electronic simulators and a tethered mockup provided valuable training but only a free-flying vehicle could provide a truly high-fidelity simulation. Hubert Drake at NASA’s Flight Research Center (known today as the Armstrong Flight Research Center) conceived a concept that became the LLRV.

Built of aluminum alloy trusses and shaped like a giant four-legged bedstead, the vehicle simulated a lunar landing profile with the help of a 4,200-pound-thrust turbofan engine mounted vertically in a gimbal. Upon reaching the maximum test altitude, the pilot then throttled back until the jet supported just five-sixths of the vehicle's weight, simulating the moon’s reduced gravity. Two variable-thrust hydrogen peroxide rockets controlled the LLRV's rate of descent and horizontal movement. Sixteen smaller hydrogen peroxide thrusters gave the pilot control in pitch, yaw, and roll.

For the initial flights on Oct. 30, 1964, research pilot Joe Walker flew the LLRV three times for a total of just under 60 seconds, reaching a modest peak altitude of 10 feet. Later flights were shared between Walker; Donald Mallick; the Army's Jack Kleuver; and Joseph Algranti and H.E. "Bud" Ream of NASA’s Manned Spacecraft Center (now the Johnson Space Center) in Houston, Texas.

The first LLRV was shipped to Houston in December 1966, followed a month later by its nearly identical twin. Three slightly larger craft joined the training fleet, and all were re-designated Lunar Landing Training Vehicles. Three of the five were later destroyed in non-fatal accidents. Fittingly, the two surviving vehicles are currently displayed at Armstrong and Johnson.

All prime and backup commanders assigned to Apollo lunar landing missions practiced in the craft and later acknowledged the benefits. Apollo 11 astronaut Neil Armstrong, first human to step onto the moon's surface, said the mission would not have been successful without the quality of simulation that resulted from the LLRV's. Other astronauts echoed these feelings.

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NASA research pilot Joe Walker prepares for a flight in the Lunar Landing Research Vehicle. Eventually, all prime and backup commanders assigned to Apollo lunar landing missions practiced in the unusual craft.

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The ungainly-looking LLRV provided research pilots and astronauts with a highly accurate lunar landing simulation. Though a crucial part of the Apollo training program, it earned the undignified nickname, 'The Flying Bedstead.'

Quelle: NASA