ABSTRACT
This chapter deals with issues relating to sleep and fatigue, and includes the basic concepts of biological rhythms, sleep/wakefulness cycles, and the nature and function of sleep. These areas are then applied to aviation with relation to time zone crossing, shift work, and sleep management. Although time awake is important in determining readiness for sleep, there is also a circadian rhythm of sleepiness. The stages of sleep are determined from the patterns of the electroencephalogram, electrooculogram, and electromyogram activity. Sleep loss, or partial sleep deprivation is an occupational hazard of commercial flying and any other form of shift work. The main problem of both time zone shifts and shift work, is that they cause desynchronization of body rhythms. The ability to gain sleep when the body is out of phase with local time is an important requirement for long-haul crews and for any pilot flying at night.
