FAA Powerplant Written Practice Test

How often should an engine be operated to ensure it achieves normal service life?

1. At least once a week

2. At least once a month

3. At least once every 30 days

4. Every flight

The correct answer is: At least once every 30 days

Operating an engine regularly is crucial for maintaining its health and ensuring it achieves its normal service life. Running the engine at least once every 30 days is recommended to prevent issues like fuel system deterioration, oil contamination, and moisture accumulation that can occur when an engine sits idle for prolonged periods. By operating the engine within this timeframe, various components receive necessary lubrication, and the combustion process helps to burn off any deposits that may form, thereby maintaining the overall functionality and reliability of the engine. This practice also helps in exercising different engine systems, which can identify potential problems before they lead to more significant issues. While more frequent operation, such as every flight or at least once a week, may provide even greater assurance of engine health, the key factor is ensuring that it runs frequently enough to mitigate the risks associated with inactivity. The recommendation of once every 30 days is a balance that helps maintain engine lubrication and minimizes the buildup of harmful substances without requiring overly burdensome frequencies.