FAA Powerplant Written Practice Test

What is the primary function of the compressor in a gas turbine engine?

1. To cool the engine

2. To supply air for combustion

3. To reduce noise emissions

4. To condense exhaust gases

The correct answer is: To supply air for combustion

The primary function of the compressor in a gas turbine engine is to supply air for combustion. This is crucial because the compressor increases the pressure and temperature of the incoming air before it enters the combustion chamber. By compressing the air, the compressor allows for a greater mass of air to mix with fuel, which in turn supports a more efficient and powerful combustion process. This step is essential for maximizing the efficiency of the engine and enabling it to perform effectively. The compressor receives ambient air and compresses it to a higher pressure, which not only enhances the combustion efficiency but also ensures that the engine operates within its designed parameters. This burnt mixture of air and fuel then expands through the turbine, generating the thrust or power required for the operation of the aircraft. Other functions such as cooling the engine, reducing noise emissions, or condensing exhaust gases are not primary roles of the compressor. Instead, they relate to different components and systems within the engine that manage thermal efficiency, noise control, and exhaust processes.