One of the 11 scientist-astronauts selected by NASA in August 1967, Allen underwent jet pilot training at Vance Air Force Base in Oklahoma, where he earned the "outstanding flying" award. He served as mission scientist, support crewman, and capcom for the Apollo 15 lunar landing in 1971. Between 1972 and 1978 he held several administrative positions while retaining his astronaut status: he was a consultant on science and technology to the President's Council on International Economic Policy in 1974, and from 1975 to 1978 he was assistant administrator for legislative affairs at NASA headquarters in Washington, DC.
After returning to the Johnson Space Center, Allen was a member of the support crew and capcom for the first Shuttle mission, STS-1.
Allen flew on two space shuttle missions, in 1982 and 1984. Allen took part in the first salvage mission in space history. As a mission specialist aboard Shuttle flight 51-A on November 1984, Allen and fellow astronaut Dale Gardner performed two space walks during which the errant satellites Palapa B-2 and Westar VI were retrieved and loaded aboard the orbiter Discovery for return to Earth.
Allen was also a mission specialist aboard the first operational Shuttle mission, STS-5 in November 1982 and supervised the first launching of a satellite, SBS-C, from the Shuttle.
Reference:
Who's Who in Space, Macmillian, 1999.