Abstract: A control system is specifically designed to improve the performance of an aircraft or other vehicle having undesirable dynamic characteristics. For this purpose there is employed a compensator, either hydromechanical or electrical (hydro-electrical) depending upon the basic control system, which is incorporated into that system and modifies command inputs to the directional controls of the vehicle. This compensator is designed and preset to impose predetermined dynamic characteristics on the command inputs so as to create a resulting input which eliminates or substantially diminishes the undesirable dynamic characteristics.