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There is plenty of literature that describes how to find the aerodynamic centers (AC) longitudinal position.

But where would it be lateral?

My guess is somewhere near 1/3 out the wing from the fuselage, but I do not know..or would it maybe be close to the mean aerodynamic chord line?

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  • $\begingroup$ This is not an answer, but usually as we have two symmetrical wings, the center in on the symmetry axis. If the wings are loaded differently, then the problem is more complex. $\endgroup$
    – mins
    Commented Apr 9, 2017 at 13:09
  • $\begingroup$ Yes, and that probably why people are more concerned about the longitudinal position. But if an aircraft had only left wing, question is, where would it be.. $\endgroup$
    – Invariant
    Commented Apr 9, 2017 at 13:17
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    $\begingroup$ That question is more relevant than the comments make it: It needs to be answered when the wing spar is sized. The sad truth is: There is a multitude of lateral aerodynamic centers, depending on angle of attack, flap settings, aeroelastic deformation and control surface deflection. It is calculated separately for each of dozens of load cases during design. $\endgroup$ Commented Apr 9, 2017 at 19:15

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For a simple tapered half wing the aerodynamic centre spanwise location is at: $$ y_{ac} = {{b}\over{6}} \cdot {c_r + 2c_t\over c_r+c_t} $$

where $b$ is the span, $c_r$ is the root chord and $c_t$ is the tip chord.

For a symmetric aircraft it should be at the centreline, since it's the combination of the two identical (but opposite sign) locations.

Source is a aicraft sizing code I wrote some years ago, I remember solving the integral for a simple tapered wing. Looking quickly at design books I can find the following image in Raymer, hope this helps:

enter image description here

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    $\begingroup$ Do you have any sources? $\endgroup$ Commented Apr 10, 2017 at 15:31
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    $\begingroup$ what do the various terms mean? $\endgroup$
    – Federico
    Commented Apr 10, 2017 at 19:02
  • $\begingroup$ Added answers in my original answer! $\endgroup$
    – Reno
    Commented Apr 11, 2017 at 15:49
  • $\begingroup$ Since an answer for an arbitrary wing shape probably would be pages of calculations. I am going to accept this answer. My question probably was too broad. $\endgroup$
    – Invariant
    Commented Apr 12, 2017 at 0:44

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