What is the purpose of feathering a propeller?

• A. Minimize drag when the engine is shut down
• B. Increase thrust during takeoff
• C. Increase RPM during climb
• D. Improve fuel economy during cruise

Answer: (A)

Feathering a propeller is about minimizing drag when the engine isn’t producing thrust. By turning the blades to a high pitch and aligning them with the oncoming airflow, the blades present as little surface area as possible, so they stop acting like a big windmill and simply ride with the air. This drastically reduces the drag the propeller would cause, which helps the airplane glide more efficiently after an engine failure or during windmilling conditions. It does not create extra thrust, nor is it used to boost RPM or cruise fuel economy—feathering is specifically about reducing drag in non-thrust scenarios.