Flight control design and simulation handling qualities assessment of high-speed rotorcraft

The U.S. Army Aviation Development Directorate has developed generic high-fidelity flight-dynamics models of two advanced high-speed rotorcraft configurations—a lift offset coaxial helicopter with a pusher propeller and a tiltrotor. The models were developed to provide the government with independent control-system design, handling-qualities analysis, and simulation research capabilities for these types of aircraft in support of the Future Vertical Lift initiate. Full flight envelope explicit model following control systems were designed for both configurations using a multi-objective optimization approach to meet a comprehensive set of stability, handling qualities, and performance requirements. The control laws for both aircraft were evaluated in a piloted simulation experiment at the NASA Ames Vertical Motion Simulator using a series of high-speed handling qualities demonstration maneuvers. This paper discusses the control laws and the results of the piloted handling qualities assessment. The results from the simulation experiment show overall assigned Level 1 handling qualities for both aircraft.