Maintaining skilled performance during extended spaceflight is of critical importance to the health and safety of crewmembers and to the overall success of the mission. During flight it is crucial to know the extent to which the astronauts are operating at levels sufficiently high to ensure safety and mission integrity. Performance in space can also be used to track the effects of weightlessness, sleep deprivation, isolation and confinement, etc.
Performance assessment is also important at other stages of mission development. For example, preflight performance assessment has been a useful tool in understanding engineering and craft-habitability constraints leading to guidelines in the layout and structural composition of spacecraft living and working quarters (Fraser,1968c; Barnes, 1969), and in instrument and control-panel designs (Shackel, 1959; Woodson and Conover, 1965). Performance assessment has also been used in the selection of astronaut candidates (Wilson, 1959; Lovelace, Schwichtenberg, Lift, and Secrest, 1962; Lamb, 1964), in their training, and in the determination of their readiness for flight (Voas, 1961; Kelly and Coons, 1967; Woodling, Faber, van Bockel, Olasky, Williams, Mire, and Homer, 1973). indeed, the measurement and evaluation of performance is basic to the role of men and women in space. In this chapter we consider performance, methods for its assessment and prediction, factors that affect performance, and possible means to sustain optimal performance.