Astronaut group 6

Astronaut Group 6 (the 'XS-11') was announced by NASA on August 11, 1967, the second group of scientist-astronauts. Only five of the eleven were given formal assignments in the Apollo program and these were all non-flying support crew positions. (Chapman was a support crew member on Apollo 14 and Apollo 16; Parker was assigned to Apollo 15 and Apollo 17; England was assigned to Apollo 13 and Apollo 16; and Henize and Allen rounded out the Apollo 15 support crew.)

Assignments for the group were delayed by the requirement to complete a full year of Air Force Undergraduate Pilot Training to become qualified as jet pilots like the Group 4 scientists before them; however, unlike the previous scientist-astronaut group, none of the selectees had previous piloting experience.

Although O'Leary (who objected to the hazards of flight training and resigned from the Astronaut Corps in April 1968) was chosen due to his professional expertise in anticipation of the proposed manned mission to Mars then tentatively envisaged for the mid-1980s, the group's moniker was derived from the perception among NASA senior managers (candidly articulated by Deke Slayton to the group on their first day of work) that they "weren't needed" due to the glut of active astronauts and looming dearth of post-Apollo funding, including the concomitant devolution of the Apollo Applications Program into Project Skylab. After "harboring qualms" about his ability to complete the flight training, Anthony Llewellyn became the second member of the group to resign in August 1968.

Subsequently, Musgrave (who cultivated a notable passion for flying, eventually accumulating over 17,700 hours in 160 different types of civilian and military aircraft) and Lenoir were assigned as backup Science Pilots in the Skylab program, while Chapman, England and Holmquest left in the early 1970s due to the paucity of flight opportunities. (England, who transferred to the U.S. Geological Survey in 1972, would ultimately rejoin the Astronaut Corps for a second nine-year stint in 1979.) The requirement for scientists to be trained as jet pilots was eventually lifted with the creation of the Mission Specialist position in the Shuttle Program. The seven members of Group 6 who stayed with the program after Apollo went on to form the core of early Shuttle Mission Specialists, accomplishing a total of 15 flights.

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