FAA Powerplant Written Practice Test

Where are the cooling fins typically located on air-cooled engines?

1. Near the fuel injector

2. On the intake manifold

3. Cylinder heads and cylinder barrels

4. At the exhaust outlet

The correct answer is: Cylinder heads and cylinder barrels

Cooling fins are strategically placed on air-cooled engines primarily on the cylinder heads and cylinder barrels. This design is crucial because these fins increase the surface area available for heat dissipation, allowing the engine to effectively cool itself as air flows over them during operation. In air-cooled engines, efficient temperature management is vital to prevent overheating, which can lead to engine failure. The fins work by allowing a larger area for the surrounding air to absorb heat away from the engine components, promoting better thermal performance. The other options do not provide effective locations for heat dissipation in air-cooled engines. Fuel injectors, intake manifolds, and exhaust outlets serve very different purposes, such as fuel delivery and gas expulsion, but they are not designed for cooling in the same way that the cylinder heads and barrels with fins are.