What is the angle of attack in relation to an airfoil?

The angle of attack is defined as the angle between the chord line of an airfoil and the direction of the relative wind. This angle is critical in the study of aerodynamics because it directly influences the lift generated by the wing. As the angle of attack increases, the lift increases up to a certain point; beyond that, the airflow can separate from the wing, resulting in a stall condition.

The distinction of the angle of attack lies mainly in how it relates to both the airfoil and the airflow. It is not merely the position of the wing relative to the horizon or the aircraft's pitch, nor does it pertain to the descent angle. Consequently, only the correct understanding of this angle in relation to both the airfoil's chord line and the incoming relative wind provides a proper basis for understanding flight dynamics and performance.