Refer to figures.

*Camber is the asymmetry between two acting surfaces on an airfoil. For a helicopter, these are the upper and lower surfaces of the rotor blades.*

**A completely symmetrical airfoil** will intersect the vertical axis of the graph at the origin (0) and generates zero lift at zero alpha.

** A positively cambered airfoil **will generate more lift at the same speed (thus, has a higher C

_{L}), than a symmetric airfoil and, therefore, intersects the vertical axis above the origin

__generating zero lift even at a negative angle of attack__.**A negatively cambered airfoil** will generate less lift at the same speed (thus, has a lower C_{L} at a certain speed), than a symmetric airfoil and, therefore, intersects the vertical axis below the origin. An example of a negatively cambered airfoil is the tail's horizontal stabilizer.

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