Which action is considered preventive maintenance under FAA regulations?

Changing the oil is categorized as preventive maintenance under FAA regulations because it is a routine task aimed at preventing future issues and ensuring the smooth operation of the aircraft's engine. Regular oil changes help to maintain proper lubrication, reduce friction, and extend the lifespan of the engine components. This proactive approach is essential in aviation, as it contributes significantly to overall safety and reliability.

While inspecting the fuel system is crucial for safety, it is classified as a necessary inspection rather than preventive maintenance. Similarly, repairing control systems and replacing the entire engine are considered corrective maintenance actions that address existing issues rather than prevent future problems. In contrast, changing the oil is a straightforward, regular task that is part of a scheduled maintenance plan designed to maintain the aircraft in optimal condition.