The flight rest requirement includes an uninterrupted sleep opportunity of how many hours?

• A. 6 hours
• B. 8 hours
• C. 10 hours
• D. 12 hours

Answer: (B)

Eight hours of uninterrupted sleep opportunity is the standard rest window. The idea being tested is that flight crews must have a solid, uninterrupted block of time during a rest period to sleep, so they can recover and perform safely on the next duties. Eight hours gives most people a full chance to enter and complete multiple sleep cycles, helping reduce fatigue when they resume flying. It also fits with general recommendations for adult sleep and with fatigue-management practices in aviation.

Six hours is usually not enough to achieve a full sleep cycle for many people, which can leave lingering fatigue. Ten or twelve hours would exceed what's typically required and would be harder to fit into schedules while still meeting duty-time limits.