Before Project Mercury, design concepts for manned spacecraft were constrained by a lack of hard facts about the human ability to function in the space environment. Many believed that electronic systems, controlled from the ground or programmed for specific contingencies, offered the only safe and practical means of operating a spacecraft. From this point of view, the person in the spacecraft was simply a passenger, an experimental subject whose main function would be to provide the physiological data needed to define the limits of a human's role in space. Mercury's designers did not completely agree with this philosophy; they conceived a spacecraft in which the pilot could take control of critical systems if necessary and would have some measure of control at all times.2
Within months of the start of Project Mercury NASA selected its first group of pilots for the early earth-orbital flights. The "Original Seven," all military test pilots* with strong engineering backgrounds, were volunteers picked from a list of more than a hundred men provided by the Pentagon [see Appendix 6].3 In view of Mercury's experimental character, the choice of test pilots was appropriate; they were accustomed to dealing with emergencies under stressful conditions and were familiar with the physical and psychological stresses of high-speed flight in unproven aircraft.
In choosing test pilots as its first astronauts, NASA came down on the side of people as active participant in spacecraft operations. It was yet to be shown how much humans could effectively participate, but the astronauts in the first group insisted on giving the pilot as much responsibility for control of the spacecraft as feasible; if the pilot did not operate the spacecraft, what was the point of a person in space (especially a test pilot)? Most of the engineers in the Space Task Group agreed with this viewpoint. In light of their long NACA experience with piloted aircraft, they too inclined toward giving pilots all the control they could safely handle.4
When the first group of astronauts entered the program in April 1959, Project Mercury and the Space Task Group were organizationally in flux. As a result, the Original Seven defined the role of the astronaut for the entire Apollo program. Administratively they reported not to any project office but directly to Robert R. Gilruth, director of the Space Task Group. For most of Gilruth's career in NACA he had worked with pilots, and he took a special interest in this group. Shortly after the astronauts reported aboard he assured them that whenever they had serious concern with any aspect of spacecraft design or mission operations he would see that they were listened to.5
Given this kind of autonomy the astronauts were considerably more than pilots in training to operate a new vehicle. While undergoing training they also took an active part in reviews of spacecraft design and operations planning, offered suggestions from the pilot's point of view, and contributed to the design of the flight simulators that soon became an important part of astronaut training. Each person was assigned an area of spacecraft systems or operations planning (e.g., attitude-control systems, communications, recovery operations) as a prime responsibility; in his specialty he closely followed developments and served as the point of contact between his astronaut colleagues and project engineers.6 Training was strongly engineering- and operations-oriented, a pattern that would be carried into subsequent projects.
* NASA originally intended to issue a general solicitation of applications for the position of "research astronaut-candidate," and considered that several occupations besides test pilot might qualify. President Eisenhower, however, directed the agency to select its astronauts from the ranks of military test pilots; this would simplify selection, keep out undesirable applicants, and eliminate the need to run security checks on the candidates.
2. Loyd S. Swenson, Jr., James M. Grimwood, and Charles C. Alexander, This New Ocean: A History of Project Mercury, NASA SP-4201 (Washington, 1966), p. 174.
3. Ibid., pp. 131, 160-63.
4. Ibid., p. 174.
5. Ibid., p. 235; John H. Glenn, Jr., interview with Robert B. Merrifield, Mar. 15, 1968, transcript in JSC History Office files. For a colorful account of the beginning of the manned space flight program, including the choice of test pilots as the Original Seven astronauts and their experiences through the Mercury program, see Tom Wolfe, The Right Stuff (New York: Farrar, Straus and Giroux, 1979). Wolfe's literary style is objectionable to many, but his treatment of Mercury is (to the present author's knowledge) well researched and is considered by many Mercury participants to accurately convey the spirit of the early days of manned space flight.
6. Swenson, Grimwood, and Alexander, This New Ocean, pp. 235-37.