12.52 Cooling Systems

12.52.2 Describe the principle components of aircraft engine air and liquid cooling systems.

Aircraft engines are cooled by two primary methods: air cooling and liquid cooling. Each system uses different components and principles to maintain safe operating temperatures.

Air Cooling System

Air cooling is commonly used in light aircraft piston engines.

Principle:
Heat is transferred directly from the engine to the surrounding airflow.

Principal Components:

• Cylinder fins: Increase surface area to improve heat dissipation.
• Baffles: Direct airflow over the hottest parts of the engine.
• Ducts: Channel cooling air efficiently through the engine compartment.
• Cowling: Encloses the engine and controls airflow to optimise cooling.

Operation:
Air enters through the cowling, is directed by baffles and ducts over the finned cylinders, absorbs heat, and is then expelled. Proper airflow management is critical to prevent overheating and uneven cooling.