The F-15 has an all-metal semi-monocoque fuselage with a large-cantilever, shoulder-mounted wing. The wing planform of the F-15 suggests a modified cropped delta shape with a leading-edge sweepback angle of 45°. Ailerons and a simple high-lift flap are located on the trailing edge. No leading-edge maneuvering flaps are used. This complication was avoided by the combination of low wing loading and fixed leading-edge camber that varies with spanwise position along the wing. Airfoil thickness ratios vary from 6% at the root to 3% at the tip.