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Seraphin2288

I'm designing the wing of a new aeromodel and I need a few informations for the structural design of the wing box that I couldn't find in the few litterature I have by now. So, here comes the question...

For the sizing of the box beam that will be the main resistant part of the wing, I need to know the location of the lift to calculate the bending moment and torque applied on the beam. The spanwise lift equation is (quite) easy to obtain for the calculation of bending moment.

My problem in then to find the chordwise location of the lift to calculate the torque applied on the wing box.

The most obvious would be to locate it at the quarter chord (aerodynamic center of the airfoil section), yet in some books they locate it at about 45% of the local chord (which would be the center of pressure, if I'm not mistaking).

Do you know which value is used in aeronautical engineering ? I thought that maybe it is equivalent to account the lift at 0.25c and add the pitching moment using the pitching moment coefficient of the airfoil or to apply a single vertical force (equal to the lift, of course) at 0.45c, but I'm really not sure...

Who could help me ?? :D

Thanks everybody !