Aviator performance in week-long extended flight operations in a helicopter simulator

Psychological, physiological, and biochemical correlates of aviator crew performance, stress, and fatigue were measured in a week-long flight schedule in a helicopter simulator. Three two-man crews of rotary wing aviators performed 14 h of precision instrument flight on each of 4 successive days and 10 h on the 5th day. Missions involved repetitions of 2-h standardized day and night flight profiles that were occasionally interrupted by simulated emergencies. Aviator performance measures included meeting assigned airspeeds, altitudes, headings, turn rates, and navigation requirements. Pilots slept 4 h each night. Baseline data were collected prior to, and recovery data after, the extended flight schedule. Pilots maintained simulator flight parameters to within acceptable tolerances of assigned headings, airspeeds, and altitudes, even into the morning of the 4th day of the schedule. However, cognitive and judgmental errors were made. Even though flight surgeons deemed them unsafe to fly by the 3rd night, pilots continued to fly well to the 5th day.