Optimizing control of a compound rotorcraft in quasi-steady maneuvers

This study investigates control allocation for a compound rotorcraft to optimize performance in acceleration, pull-up, and turning maneuvers. Simulations of a hypothetical compound rotorcraft based on a UH-60A airframe and main rotor with a wing and pusher propeller are used. The study presents general background on the simulated compound rotorcraft's performance in trim and the trim methodology employed. In addition to the four traditional controls, this study explores two additional control effectors: propeller pitch and symmetric wing flap deflection, which can be optimized for performance in trim or maneuvering flight. Trim analysis of quasi-steady maneuvers is used to gain an understanding of the control allocation that minimizes power required. The results of the optimization are incorporated into a g-command model inversion controller to regulate longitudinal and vertical load factor. A combined longitudinal and vertical load factor command controller is used to ensure optimal control allocation with regards to the propulsive force distribution between the main rotor and propeller, and the lift force distribution between the main rotor and wing.