Human Performance for Military and Civilian Operations in Space

It is now almost four years since the first astronaut, Gagarin, orbited the earth in a space vehicle on 12 April 1961. Since his exploit, there have been four American and six Russian manned orbital flights of varying durations up to 120.7 hours. From these flights much has been learned about human performance capabilities in space, which is the subject of this paper. There is no longer any doubt, for example, that astronauts can provide the same quality of human judgment, decision making, and skilled manual performance that we have learned to expect of test pilots. In most of the Project Mercury fights the astronauts contributed greatly to successful mission completion through their ability to take over vital control functions and manually override malfunctioning automatic equipment. The value and contribution of man in many types of space vehicles has certainly been demonstrated beyond question. The manned space flights up to now, however, have explored only a limited part of the total spectrum of human activities being considered for future flights. With minor exceptions, all the astronauts remained tied in their seats. Except for the firing of retrorockets for re-entry, they have maneuvered their vehicles only in attitude. Future flights, already planned or being seriously considered, call for astronaut activities and capacities that go far beyond those already accomplished. Among the major astronaut activities being considered for future flights are: 1. Missions of much longer duration, extending into weeks and months. 2. Locomotion inside vehicle to perform maintenance, scientific experiments,