Overview
Fatigue is a physiological state of reduced mental or physical performance capability resulting from lack of sleep or increased physical activity that can reduce a pilot's alertness and ability to safely operate an aircraft or perform safety-related duties. Fatigue is a very common factor associated with pilot error. Fatigue has been a major contributor to countless aircraft accidents in both general and commercial aviation. Fatigue is such a serious threat to safety that it was one of the NTSB's "Most Wanted" safety improvements in the transportation industry.