Hi Sonja, @1:31, you say that the aerodynamic center does not stay at the same place. Isn't the aerodynamic center defined as a point (at about 25% of chord) about which the pitching moment is constant? Isn't it therefore constant by definition? Thanks for your help.
The AC mentioned here is the wing AC. It shifts with angle of attack. The 25% chord is an arbitrary reference point. The wing AC is at 25% chord if the pitching moment of the wing around this point happens to be zero.
Hi Sonja,
@1:31, you say that the aerodynamic center does not stay at the same place.
Isn't the aerodynamic center defined as a point (at about 25% of chord) about which the pitching moment is constant? Isn't it therefore constant by definition?
Thanks for your help.
The AC mentioned here is the wing AC. It shifts with angle of attack. The 25% chord is an arbitrary reference point. The wing AC is at 25% chord if the pitching moment of the wing around this point happens to be zero.