Patent US 5,951,608

The disclosed flight control system includes a rotor blade speed monitor for monitoring the rotor blade speed of the jet powered tri-mode aircraft and for outputting a rotor blade speed command. The flight control system also includes an aircraft attitude controller for controlling the aircraft attitude of the jet powered tri-mode aircraft. Weighted rotor blade attitude stabilization commands and weighted aero surface attitude stabilization commands are output from the aircraft attitude controller to distribute power, control, and lift between the rotor blade and the aero surfaces. Relative weights of the weighted rotor blade attitude stabilization commands decrease with increasing aircraft travelling velocities, and relative weights of the weighted aero surface attitude stabilization commands increase with increasing velocities. A rotor blade lift controller receives the weighted rotor blade attitude stabilization commands and the rotor blade speed commands, and positions the rotor blade swashplate to adjust lift and control according to these commands. An aero lift controller receives the weighted aero surface attitude stabilization commands and deploys the aero surfaces to generate lift and control according to the received weighted aero surface attitude stabilization commands.