ANY Airfoil's Angle Of Attack or AOA (4) is an aerodynamic one.
It is: The angle between the airfoil chord line and its
direction of motion relative to the air (the resulting Relative
Wind). Several factors will affect rotor blade AOA. Some are
controlled by the pilot and some occur automatically due to the
rotor system design. Pilots are able to adjust AOA by moving the
cyclic and collective pitch controls. However, even when these
controls are held stationary, the AOA constantly changes as the
blade moves around the circumference of the rotor disk. Other
factors affecting AOA, over which the pilot has little control,
are: AOA is one of the primary factors that determines amount of
lift and drag produced by an airfoil. Angle of attack should not
be confused with the Angle Of Incidence. Angle of Incidence (or
AOI) is the angle between the blade chord line and the plane of
rotation of the rotor system. It is a mechanical angle rather
than an aerodynamic angle: In the absence of induced flow and/or
aircraft air