This is a quite well researched documentary. However, Mike Collins never flew the X-15 rocket plane as stated. The only member of the Apollo 11 crew who did fly the X-15 was its commander, Neil Armstrong, when he was a civilian test pilot. Mike Collins said in his superb autobiography "Carrying The Fire" that Neil was far and away the most experienced test pilot of all the astronauts because he had flown the X-15.