Private Pilot License (PPL) Aerodynamics Practice Exam

What factor does not affect the angle of attack at which an airplane wing stalls?

1. Aircraft's weight

2. Aircraft's attitude

3. Aircraft's airspeed

4. Angle of descent

The correct answer is: Aircraft's weight

The angle of attack at which an airplane wing stalls is primarily influenced by factors such as the aircraft's attitude, airspeed, and the dynamics of the flight itself, including the angle of descent. The concept of stall is related to the relationship between the wing's angle of attack and the airflow over the wing. Each wing has a critical angle of attack, beyond which the airflow can no longer smoothly adhere to the wing surface, leading to a loss of lift. Weight, while it affects the overall performance and load on the aircraft, does not directly alter the critical angle of attack for stall. Whether the aircraft is lightly loaded or heavily loaded, the fundamental characteristic of the wing regarding its stall angle remains constant. Therefore, the wing will stall at the same angle of attack regardless of weight variations. In contrast, aircraft attitude influences the angle of attack as it determines the relative position of the wing concerning the oncoming airflow. Airspeed also plays a role since it affects lift generation, but the stall angle itself remains immutable regardless of weight. The angle of descent can affect how quickly an aircraft reaches that stall angle, but it is not a factor that changes the angle of attack at which the stall occurs. Thus, the correct understanding is that