The Aerodynamic Action of Triangular Horn-Balanced Control Surfaces on the Supersonic Delta Wing

g(<r, n) = hinge moment increment function defined bv Eq.(9) h{\, n) = hinge moment increment function defined b}^ Eq. (20) Lv = control lift due to control deflection f(a, n) = control lift increment function defined by Eq. (29) The pressure distribution of a supersonic delta wing in the region of influence of a deflected flap type of control with a triangular horn balance is determined on the basis of linearized theory. Both subsonic and supersonic leading edges are considered. General formulas for the control hinge moment increments AHa, AHV are calculated to estimate the effectiveness of an aerodynamic balance of the type considered, and corresponding formulas for the increment in the lift ALV are also developed. The final expressions for the increments are expressed as functions of the delta wing parameter n = tan r tan fx ( r being the leading-edge sweepback and fi the free-stream Mach angle) and a geometrical parameter determined by the control surface configuration. These functions are represented graphically. The results are applicable to full span flaps, provided the Mach waves from the apex of each balance do not intersect the balance area or the leading edge of the opposite wing, and to partial span flaps if the inboard edge does not lie within the Mach cone from the apex of the balance. Formulas for the total hinge moments are given in the case of full span flaps.