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Cambered airfoils generate induced drag because they have a pressure differential between the upper and lower surface. However symmetrical airfoils don't. So does this mean that symmetrical airfoils have no induced drag? enter image description here

Image source:https://en.m.wikipedia.org/wiki/File:Airfoil_camber.jpg

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    $\begingroup$ The airfoils alone don't - but the wings made with them do. Especially if they have finite span and produce lift. $\endgroup$ Jun 26 at 14:05

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If an airfoil is producing lift, then it will be producing induced drag.

Both cambered and symmetrical airfoils have an angle of attack at which they produce no lift, no induced drag, and no pressure difference between top and bottom. While this angle lines up nicely with the geometrical mid line of the symmetrical airfoil, it is offset from the apparent mid line of the cambered airfoil.

The cambered airfoil can produce more lift before the stall in the 'normal' lift direction, which is why it tends to be used for surfaces loaded in only one direction, like wings. A symmetrical airfoil would be used for control surfaces which might see equal loading in either direction.

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It depends on the angle of attack. If it is non-zero there will still be a different airflow on both sides - leading to different pressures and thus induced drag.

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