What does the angle of attack of a fixed pitch propeller depend on?

The angle of attack of a fixed pitch propeller is determined by both the forward speed of the aircraft and the engine speed because these two factors work together to influence the performance of the propeller.

When the engine speed increases, the rotational speed of the propeller blades increases, which can raise the angle of attack and improve thrust. Conversely, when the forward speed of the aircraft increases, the air flowing over the propeller blades can also affect the angle at which the blades meet the oncoming airflow.

Thus, the interaction between forward speed and engine speed creates varying conditions that affect the propeller's angle of attack. This adaptability is essential for optimizing performance during different phases of flight, such as takeoff, cruising, and landing. Understanding this relationship helps in achieving efficient propulsion and maintaining control of the aircraft.