THE PITCH-YAW-ROLL COUPLING PROBLEM OF GUIDED MISSILES AT HIGH ANGLES OF PITCH
NAVAL ORDNANCE LAB WHITE OAK MD WHITE OAK United States
Pagination or Media Count:
A study has been made of the pitch-yaw-roll coupling problem to determine a how the problem arises, b the general effects of this coupling on the flight of missiles, and c how the adverse effects of the coupling can be minimized. The coupling results primarily from the fact that at high angles of attack, the pressure on the windward side of the missile is greater than on the lee side. For equal deflections of the vertical control surfaces, the surface on the windward side will produce a higher force than the one on the lee side, thereby producing a rolling moment as well as a side force. In addition, when the angle of pitch and the angle of roll are not equal to zero, the vortices from the fuselage nose introduce control surface forces in such a manner as to cause a rolling moment, which a so affects the coupling. The general effects of this coupling have been to render some missiles uncontrollable under certain conditions of angle of pitch and Mach number, and other missiles to become merely more difficult to control precisely. These adverse effects may be minimized by proper guidance systems and aerodynamic design.