Why is flying in a fatigued state considered hazardous?

Flying in a fatigued state is considered hazardous primarily because it impairs a pilot's cognitive functions and decision-making abilities. Fatigue can lead to slower reaction times, diminished situational awareness, and decreased attention to detail. When a pilot is fatigued, they may struggle to process information effectively, which can compromise their ability to manage the aircraft and respond to challenges or emergencies.

While longer flight times, increased fuel consumption, and complicated navigation might be factors that arise indirectly from operational decisions, the core issue is the impairment of the pilot's mental and physical capabilities. This impairment creates a risk not only for the pilot but also for passengers and others in the airspace. A fatigued pilot may fail to recognize critical situations or make poor judgment calls, which can lead to severe consequences. Thus, recognizing fatigue as a state of impairment highlights the critical importance of ensuring pilots are well-rested before flying.