What does Part 117 emphasize regarding duty fitness?

Part 117 focuses on the fitness for duty of crew members and emphasizes the importance of ensuring that pilots are in optimal physiological and psychological condition to perform their responsibilities effectively. This regulation acknowledges that fatigue can significantly impair a crew member's performance, making it critical that all flight crew members are fit for duty before operating an aircraft. This ensures both safety and compliance with regulations designed to minimize fatigue-related risks.

The options regarding specific training, wellness checks for passengers, or limitations on who it applies to do not directly align with the core intent of Part 117. Rather, it is centered around the responsibility of the crew to assess their own fitness for duty as a primary safety measure. Ensuring that crew members are fit for duty directly contributes to maintaining the highest safety standards in flight operations.