Buzz Aldrin on July 20, Aldrin and Armstrong entered "Eagle", and began the final preparations for lunar descent. At 17:44:00 "Eagle" separated from the "Columbia". Collins, alone aboard "Columbia", inspected "Eagle" as it pirouetted before him to ensure the craft was not damaged, and that the landing gear was correctly deployed. Throughout the descent, Aldrin called out navigation data to Armstrong, who was busy piloting the "Eagle". Five minutes into the descent burn, and above the surface of the Moon, the LM guidance computer (LGC) distracted the crew with the first of several unexpected alarms that indicated that it could not complete
Buzz Aldrin fell to Aldrin to complete Gemini's EVA goals. NASA formed a committee to give him a better chance of success. It dropped the test of the Air Force's astronaut maneuvering unit (AMU) test that had given Gordon trouble on Gemini 11 so Aldrin could focus on EVA. NASA revamped the training program, opting for underwater training over parabolic flight. Aircraft flying a parabolic trajectory had given astronauts an experience of weightlessness in training, but the delay between parabolae imposed a rest period. It also encouraged performing tasks quickly, whereas in space they had to be done slowly and deliberately. Training