Lunar Landing Research, 45 Years Ago

Forty-five years ago today — October 30, 1964 — NASA pilot Joseph Walker took off from the South Base area of Edwards Air Force Base on the first flight in a Lunar Landing Research Vehicle (LLRV).

(LLRV in flight. NASA image ECN-506, from the NASA Dryden photo collection.)

Walker flew the vehicle three times that day; his total flight time was just under 60 seconds, and he reached a peak altitude of about ten feet. That may not sound too impressive, but think about how difficult the thing must have been to fly:

Built of aluminum alloy trusses and shaped like a giant four-legged bedstead, …. the LLRV had a General Electric CF-700-2V turbofan engine mounted vertically in a gimbal, with 4,200 pounds of thrust. The engine got the vehicle up to the test altitude and was then throttled back to support five-sixths of the vehicle’s weight, simulating the reduced gravity of the moon. Two hydrogen peroxide lift rockets with thrust that could be varied from 100 to 500 pounds handled the LLRV’s rate of descent and horizontal movement. Sixteen smaller hydrogen peroxide rockets, mounted in pairs, gave the pilot control in pitch, yaw and roll.

And remember, all of this was done with primitive computers by today’s standards. Today, we might build it so that a control computer would measure the vehicle’s movements and its shifting center of gravity, and compensate automatically; they didn’t have that luxury, which to me makes their accomplishment even more impressive.

Eventually the three LLRVs were sent to Houston, and joined by two Lunar Landing Training Vehicles (LLTVs), which lunar module pilots used to train for the descent to the moon. Without them, the Apollo lunar landings would have been much more difficult — maybe impossible.

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