Adding slots between segments will make those work even better than a solid airfoil and allow to use more camber. So higher camber airfoil generate more lift then lower camber airfoil at the same angle of attack, I am talking about positive lift. Again, as soon as a lot of lift at low speed is needed, thin, highly cambered airfoils are the best choice. Answer (1 of 2): Higher the camber, greater the asymmetry. 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. Thin Airfoil Theory Setup Non-penetration condition Kutta condition Bernoulli Assumptions: 1. 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. Focus on the thickness and the mean cambered airfoil not to. The real meaning of the the family of airfoils is the meaning of the constant mean camber. When its thickness goes to zero, then the mean camber of the airfoil is the same as the undercambered. 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 airfoil gets thinner till it becomes undercambered. First propeller use: A highly cambered airfoil would cause high pitching moments and twist the propeller blade.
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