How often must a crewmember operate the airplane emergency equipment after initial training?

The correct interval for a crewmember to operate the airplane emergency equipment after initial training is 24 calendar months. This requirement is established to ensure that crewmembers maintain their skills and familiarity with the emergency equipment, which is essential for safety in the event of an emergency. Regular practice helps to reinforce the knowledge and proficiency required to operate such equipment effectively. Allowing a longer duration, such as 24 months, can be critical, as it ensures that crewmembers have enough time to refresh their skills, which could be vital in a real emergency scenario.

In contrast, intervals such as 6, 12, or 18 months may not align with regulatory requirements, and shorter intervals might not allow for adequate retention of emergency procedures and equipment use.