A reversible camber airfoil rib has a first side and a second side that are adjoined at an angle along an interrupted common inner edge extending longitudinally from a leading edge to a trailing edge. An aperture extends through the common inner edge and enables the rib to pivotally couple with a mast about an axis that is transverse to the mast axis. The aperture also allows the rib to slide along the mast. Each of the sides of the rib has a cambered outer edge which supports an airfoil surface. A plurality of the ribs and attending components when enclosed in a flexible covering provides a reversible camber airfoil for use on a wind-powered vehicle.