What defines fatigue according to the International Civil Aviation Organization?

The correct answer outlines fatigue as a state of reduced performance capability, which aligns with the understanding of fatigue within aviation safety and operational contexts according to the International Civil Aviation Organization (ICAO). This definition emphasizes that fatigue diminishes an individual's ability to perform tasks effectively, which is critical to ensuring safety in aviation operations.

When crew members experience fatigue, their cognitive functions, reaction times, and overall awareness can become compromised, potentially leading to errors or accidents. This understanding is essential for managing crew schedules, implementing resting protocols, and enhancing training programs that aim to combat fatigue in aviation. Recognizing fatigue as a condition that can significantly undermine performance is vital for maintaining safety standards in the industry.