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NACA 2412
Airfoils can generally be described by the formulas laid out by the National Advisory Committee for Aeronautics (NACA), an aerospace agency that immediately preceded NASA. The NACA 2412 airfoil has a camber (the degree to which the airfoil is asymmetrical) of 2 percent, with the maximum camber located 40 percent of the way from the leading edge of the foil. The maximum thickness of the wing is 12 percent of the length of the "chord" -- the distance between the leading edge of the airfoil and its trailing edge. This airfoil is, therefore, of medium thickness, suitable for relatively high lift and low speeds; this is the airfoil used in most Cessna aircraft, including the Cessna 172, 182 and 208.
NACA 23018
Compared to the NACA 2412, the 23018 airfoil is designed for greater comparative lift. It has a slightly lower camber of 1.8 percent and a substantially greater chord thickness of 18 percent, producing a wing that produces more lift -- a lift coefficient of .3. The 23018 is useful for aircraft that travel relatively slowly (compared to jets) but require large amounts of lift, such as the Lockheed 1049 Constellation, a propeller-driven airliner of the 1940s and '50s.
BAC 449-451
Modern airliners have more complex airfoils that can't always be accurately described by NACA formulae. The Boeing 737, for example, has a wing with a variable-chord airfoil -- different at the wing roots, midsection and tip. The foil is thinner -- between 10 and 15 percent of the chord length -- which offers less drag at the jetliner's higher speeds; the camber is also less than that found on propeller-driven aircraft, ranging from .2 to 1.45 percent.
NACA 43012
Glider aircraft also have complex airfoils -- they need to be able to generate lift over a wide range of different airspeeds and angles of attack. The 43012 airfoil, used on gliders such as the Schweizer 2-33, is thin like the BAC 449 but has a much greater camber of 3.4 percent; viewed from the side, the airfoil is markedly asymmetrical, with the thickest part of the upper camber coming near the leading edge of the foil and the thickest part of the lower camber located much closer to the trailing edge.
NACA 64A010
Early jet fighter aircraft, like Grumman's F9F, used foils similar to the 64A010 -- this airfoil has no camber at all, being symmetrical when viewed from the side. This means that with a zero-degree "angle-of-attack" -- how far up or down the aircraft is pitched -- the wing generates no lift. It's a thin wing, too, intended to produce low drag as the maximum thickness is only 10 percent.
NACA 65108
Thinner wings are still known as "supercritical" airfoils, and they generally see use in aircraft designed to operate primarily or exclusively at supersonic speeds where most of the lift can come from the angle-of-attack and the most important thing is reducing drag generated by the foil. The 65108 airfoil, seen from the side, is almost completely flat -- it's notable as the airfoil used on the Bell X-1, the first aircraft to break the sound barrier.