What is Angle of Attack (AOA)
Angle of attack definition
The angle of attack (AOA) or aerodynamic angle is the angle between the chord line of the airfoil (wing) and the direction of the relative wind which you can see in the image below.
Changing Angle of Attack
If the angle of attack increases, the lifting force and induce drag will increase to a certain point. The excessive angle of attack (usually more than 17 degrees) causes the air flowing on the upper surface of the wing to separate from it and, leading to a loss of lift force, which is called a stall.
As you can see in the figure below, as the angle of attack increases, the lift force increases to a certain point, and then the lift force decreases and the wing reaches the stall. The point at which the wing enters the stall is called the critical angle of attack (Stalling Angle of Attack).