Reconfigurable Flight Controls

For the military helicopter in combat, the loss of a control surface under any circumstance usually translates into either an emergency landing or complete loss of control. A critical factor in determining the pilot's chance of maintaining control is the level of redundancy in control effectors, or more correctly, the lack of such redundancy. Unlike fixed-wing aircraft, the control effectors on the conventional helicopter are integrated, so that, in the event of a failure, the pilot's task of determining the proper control strategies and continuing to a safe landing is extremely difficult. There is a potential for assisting the pilot on future designs by implementing reconfigurable flight control system (RFCS) algorithms. Such approaches are showing promise for fixed-wing aircraft; their application to helicpoters, however, requires a recognition of the distinct differences between fixed- and rotary-wing aircraft controls and responses. This proposal presents an approach to the subject starting with demonstrating the feasibility of producing a controllable impaired aircraft. If funded, the Phase I work will examine all possible failures for a current helicopter, focusig on one example critical failure. For this failure the feasible flight control laws to provide Level 3 (or better) flying qualities will be dveloped.