What defines the angle of attack (AOA) in aviation?

The angle of attack (AOA) is defined as the angle between the wing's chord line and the direction of the relative wind. This measurement is critical in aviation as it directly influences lift and drag forces acting on the aircraft.

The wing's chord line is an imaginary straight line that extends from the leading edge to the trailing edge of the wing, while the relative wind is the airflow direction as the aircraft moves through the air. As the angle of attack increases, the lift generated by the wing also increases up to a certain point, after which the wing may stall if the AOA becomes too steep.

Understanding this concept is vital for pilots as managing the angle of attack affects the aircraft's performance during different phases of flight, particularly during takeoff, cruising, and landing. By monitoring AOA, pilots can optimize performance and ensure safe flight operations.