Circadian Rhythm

Definition

The body natural 24-hour biological clock that regulates sleep-wake cycles. Disruption from jet lag, night flying, or irregular schedules increases fatigue risk and degrades cognitive performance.

Related Terms

Fatigue

A state of physical or mental exhaustion that degrades pilot performance. Fatigu...

Duty Time Limitations

Regulations limiting the number of hours a pilot can fly and requiring minimum r...

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