Comments by "Gort" (@gort8203) on "End of the Spits – The Supermarine Spiteful and Seafang" video.

You have probably read too many of those stories about the Bernoulli principle and that it takes a cambered wing to produce lift. A completely symmetrical airfoil produces lift given an angle of attack. Even flat plate will produce lift.
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@KevTheImpaler A symmetrical airfoil will fly just as well inverted as it does upright. At zero angle of attack it does not produce lift. A positively cambered airfoil will produce lift even at zero AOA, and you have to go to a slight negative AOA to get zero lift. They are not so efficient at inverted flight and required a more exaggerated negative AOA to fly level inverted. Symmetrical or near symmetrical airfoils are common on high performance and aerobatic aircraft.
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