An auxiliary wing and flap assembly for an aircraft which is to be extendable from a retracted position to a deployed position. Relative to the chord of the wing, the split flap is located directly adjacent the trailing edge of the wing with the auxiliary wing assembly being located at approximately the mid length of the chord of the wing. A split flap assembly extends approximately one-half the length of the aircraft wing with the auxiliary wing assembly extending the total length of the aircraft wing. The split flap is extendable to assume approximately a sixty degree angle relative to the bottom surface of the aircraft wing while the auxiliary wing assembly is extendible to assume a maximum of ninety degree angle relative to the bottom surface of the aircraft wing. The chord length of the split flap is equal to approximately 0.15 of the chord length of the aircraft wing while the auxiliary wing assembly has an airfoil-shaped member that has a chord length of approximately 0.25 the chord length of the aircraft wing.