Cowl Flaps

Adjustable openings on the engine cowling that regulate the amount of cooling air flowing over the engine cylinders. Cowl flaps are opened during high-power, low-airspeed operations (such as climb and ground operations) to increase cooling airflow and prevent the engine from overheating. They are typically closed during cruise flight to reduce aerodynamic drag and allow the engine to reach optimal operating temperature. The pilot monitors cylinder head temperature to determine the appropriate cowl flap position.