Again, as soon as a lot of lift at low speed is needed, thin, highly cambered airfoils are the best choice. Note that aircraft with a high wing loading use extensive and extensible high lift devices which turn their wings into thin, highly cambered structures for landing. This is similar to the use on propellers: A wider operating range requires to move away from the narrow optimum offered by those highly cambered airfoils. As soon as the aircraft needs to cover a wider speed range, however, a lower camber is needed to keep drag low at high speed. Those with low maximum speed like human powered or electric propulsion aircraft prefer those airfoils because they create the needed lift at the lowest possible speed, so the aircraft can fly with the limited installed power. Use on wings: Some aircraft do indeed use highly cambered airfoils. Those are more stubby and enjoy much narrower variations in flow conditions, so the highly cambered, thin airfoil is indeed the best choice here. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features Press Copyright Contact us Creators. Note that indeed thin, highly cambered airfoils are used on compressors and turbines in jet engines. In off-design points (i.e., most of the time) the propeller would have poor performance when compared with one which tolerates more diverse conditions. Of course you can pre-twist the blade so it will assume the correct shape in the desired operating point, but a propeller needs to work over a wide range of operating points, from take-off roll to high speed flight at altitude. The first reference also I have seen, but could not implement effectively the different approcahes suggested over there. First propeller use: A highly cambered airfoil would cause high pitching moments and twist the propeller blade. The idea being to get back the thickness and camber distribution for any arbitrary airfoil (with high camber).
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