The operational environment in which the professional airline pilot functions was described. A study conducted by the Air Line Pilots Association (ALPA) in 1963 revealed that the aeromedical profession and related disciplines had insufficient information and were unable to test and measure fatigue and elements affecting it. The ALPA helped to form a University Study Group on Human Factors in Air Line Air Safety that was to be sponsored by Wright State University. Factors mentioned in the report on a an aircraft crash were fatigue, long duty hours and excessive workload, inadequate nutrition, and poor weather. Environmental factors in jet flight in general included relative hypoxia at cabin altitudes between 5000 and 10,000 feet, along with possible temperature extremes, low humidity, vibration, and noise. Scheduling factors were influenced by economic, statutory, political, operational, labor management, and some nonverbalized variables. Main areas of concern to pilots were transmeridian flight operations, long duty hours, and disruption of biologic rhythms. Duty times were usually long, with multiple short segments, many takeoffs and landings, high workload in crowded airspace, congested airfields and delays that could ruin a schedule. The average professional pilot worked 15 to 18 days per month. Required attention and mental workload were high. Pilots suffered diurnal shifts. Approximately 20 percent of pilots were on call and had to be available on short notice. The author concludes that pilots are now asking for guidance on how to better prepare themselves mentally, physically, and nutritionally for almost constant shift in work schedules.
The Twenty-Four Hour Workday: Proceedings of a Symposium on Variations in Work-Sleep Schedules, Division of Biomedical and Behavioral Science, NIOSH, U.S. Department of Health and Human Services, Cincinnati, Ohio, DHHS (NIOSH) Publication No. 81-127