What controls the amount of air cooling in a pressure cowling system?

What controls the amount of air cooling in a pressure cowling system?

• A. The throttle position.
• B. The exit air is controlled by cowl flaps.
• C. The fuel-air mixture ratio.
• D. The engine oil level.

Answer: (B)

In a pressure cowling, the cooling air flow is regulated by how easily air can exit the cowling. The exit air is controlled by the cowl flaps, which open or close to adjust the amount of air that can leave through the cowling. When the flaps open, more air can escape, increasing cooling of the engine fins and cylinders. When they close, the exit is restricted, reducing cooling. Throttle position, the fuel–air mixture, and engine oil level influence how much heat the engine generates, but they don’t set the rate of cooling air flow through the cowling. The primary control of cooling air in this system is the cowl flaps.

In a pressure cowling, the cooling air flow is regulated by how easily air can exit the cowling. The exit air is controlled by the cowl flaps, which open or close to adjust the amount of air that can leave through the cowling. When the flaps open, more air can escape, increasing cooling of the engine fins and cylinders. When they close, the exit is restricted, reducing cooling.

Throttle position, the fuel–air mixture, and engine oil level influence how much heat the engine generates, but they don’t set the rate of cooling air flow through the cowling. The primary control of cooling air in this system is the cowl flaps.