Project Mercury also excluded civilian NASA X-15 pilot Neil Armstrong, though he had been selected by the US Air Force in 1958 for its Man In Space Soonest program, which was replaced by Mercury. Although Armstrong had been a combat-experienced NAP during the Korean War, he left active duty in 1952. Armstrong became NASA's first civilian astronaut in 1962 when he was selected for NASA's second group, and became the first man on the Moon in 1969. It was further stipulated that candidates should be between 25 and 40 years old, no taller than , and hold a college degree in a
Neil Armstrong X-1B. He flew the North American X-15 seven times, including the first flight with the Q-ball system, the first flight of the number 3 X-15 airframe, and the first flight of the MH-96 adaptive flight control system. He became an employee of the National Aeronautics and Space Administration (NASA) when it was established on October 1, 1958, absorbing NACA. Armstrong was involved in several incidents that went down in Edwards folklore or were chronicled in the memoirs of colleagues. During his sixth X-15 flight on April 20, 1962, when Armstrong was testing the MH-96 control system, he flew to a