“Going to two,” replied Armstrong. "Coming up on eight minutes.’’ “HEY, THERE IT IS!": PITCIIOVER AND P64

After about nine minutes, when P63 had delivered the LM to high gate, typically only 2,200 metres up and 7.5 kilometres from landing, control was passed to Program 64, whose role it was to guide the LM through the approach phase to a point just above the landing site. Many aspects of the descent changed at this point. In particular. P64 did not continue the effort by P63 to reach a point below the surface. Prior to high gate, the crew’s windows had been facing into space, so one of P64’s first actions was to give the crew a chance to see where it was taking them. It fired the RCS thrusters to pitch the spacecraft forward sufficiently to enable the crew to view the horizon ahead – a manoeuvre called pilchover. This change in attitude with respect to the ground meant that the antenna for the landing radar had to rotate to its second position so as to continue to face roughly downwards. Meanwhile, P64 continually rode the engine’s throttle setting to aim for a point 30 metres above and five metres short of where it thought the final landing site was located.

As Pete Conrad waited for P64 to begin, he strained at his window to look for a familiar pattern of craters towards which he had trained to fly. Careful correlation of photographs taken two years earlier by a Lunar Orbiter mission with surface pictures taken by the Surveyor 3 unmanned spacecraft had shown that it had landed within a 200-metrc-diameLer crater that formed the torso of a distinctive pattern of five craters known as the Snowman. Planners had decided that this would make a good target to prove the pinpoint landing capabilities of the Apollo system.

“Standing by for P64.” he told Л1 Bean standing beside him. “I’m trying to cheat and look out there. I think 1 see my crater.” He was the shortest of the astronauts, and was straining against the harness restraint to see the lunar surface in the bottom corner of his triangular window. He had not yet seen his crater.

“Coming through 7,” said Bean as they passed 7,000 feet or 2,150 metres. “P64 Pete.”

“P64,” confirmed Conrad.

“Pitching over,” said Bean as the LM began to tip forward.

“That’s it; there’s LPD,” said Conrad as he brought up the angle display of the landing point designator.

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