AFOQT Practice Test

Which propeller type has a blade angle that cannot be changed by the pilot?

1. Variable pitch propeller

2. Fixed pitch propeller

3. Turbo-propeller

4. Multi-blade propeller

The correct answer is: Fixed pitch propeller

The correct response is that the fixed pitch propeller has a blade angle that cannot be adjusted by the pilot. In a fixed pitch propeller, the angle of the blades is set at a specific angle during manufacturing and remains constant while the aircraft is in operation. This means that the performance characteristics of the propeller, such as thrust and efficiency, are predetermined, making it simpler but less versatile compared to other types of propellers. In contrast, a variable pitch propeller allows the pilot to adjust the blade angle during flight, enabling better performance in different phases of operation, such as takeoff, cruising, and landing. Turbo-propellers can also have variable pitch blades, and while multi-blade propellers refer to the number of blades and can be fixed or adjustable, they do not inherently dictate adjustability of the pitch. The fixed pitch design is straightforward and reliable, making it an effective choice for certain types of aircraft, especially those with less complex performance requirements.