FAA Powerplant Written Practice Test

How is an aircraft engine classified when it has been operated continuously for at least one hour within the past 30 days?

1. Inactive storage

2. Active storage

3. Temporary storage

4. Normal operation

The correct answer is: Active storage

When an aircraft engine has been operated continuously for at least one hour within the past 30 days, it is classified as active storage. This classification indicates that the engine is not in a dormant state but has been used recently, thus maintaining its readiness for operation. Active storage suggests that the engine's components are being kept in good condition due to the recent operational use, which helps prevent issues like corrosion or the degradation of lubricants and seals. Regular operation ensures that moving parts are adequately lubricated and that the engine is functioning within its designed parameters. The other classifications, such as inactive storage and normal operation, do not apply in this context because inactive storage refers to engines that have not been operated for a predetermined time, and normal operation implies continuous use without interruption rather than a recency within the last 30 days. Temporary storage often implies a short-term status but does not specifically denote the operational use criterion required for active storage classification.