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Cowl Flap Controls: How Pilots Open and Close Cowl Flaps


Cowl flaps play an important role in regulating engine temperatures in many airplanes. Located at the bottom of an engine’s cowling, they increase airflow to keep temperatures in check. Air will flow into the cowling and around the engine, thereby regulating the engine’s temperature so that it doesn’t overheat.

Cowl flaps, however, support different positions. They can be open, or they can be closed. Open cowl flaps promote airflow while subsequently providing greater cooling power for the airplane’s engines. Closed cowl flaps, in comparison, restrict airflow. So, how do pilots open and close cowl flaps?

Overview of Cowl Flap Controls

If an airplane has cowl flaps, the controls for it will likely be located in the cockpit. Using these controls, pilots can open and close the airplane’s cowl flaps.

Cowl flap controls allow pilots to open and close the airplane’s cowl flaps. As previously mentioned, cowl flaps in the open position will promote airflow around the airplane’s engines, whereas cowl flaps in the closed position will restrict airflow. Pilots can specify the desired cowl flap position via the cowl flap controls in the cockpit

When Do Pilots Use the Cowl Flap Controls?

Pilots will typically open the airplane’s cowl flaps prior to takeoff. This is because takeoffs require a significant amount of engine power while maintaining low airspeed.

Due to the low airspeed associated with takeoff, airplanes often require supplementary cooling, which is where the cowl flaps come into play. By opening the cowl flaps, pilots can help regulate the airplane’s engine temperatures during takeoffs and other low-airspeed operations. Once the airplane has achieved cruising altitude, pilots will typically close the cowl flaps.

Manual vs Automatic Cowl Flaps

While most cowl flaps support manual operation via cowl flap controls in the cockpit, some of them work automatically. They are designed to open and close automatically in response to factors such as engine temperature and airspeed.

If the airplane’s engine or engines get too hot, the cowl flaps may open automatically to facilitate airflow. Alternatively, if the airplane’s airspeed drops too low, the cowl flaps may open automatically. Automatic cowl flaps such as these don’t require manual operation; pilots can focus their attention elsewhere while allowing the automatic cowl flaps to open and close accordingly.

In Conclusion

Airplanes may have automatic or manual cowl flaps. Those with manual cowl flaps have controls in the cockpit. Using these controls, pilots can open and close the airplane’s cowl flaps.