Abstract: A fluidic stiffness enhancing circuit for use with a fluid driven piston type actuator includes a fluid conduit arrangement that interconnects two variable volume chambers of the actuator upon occurrence of a loss of system pressure to at least one of the chambers. The fluid conduit arrangement incorporates an inertance device for controlling the rate of flow of fluid therethrough so as to control the pressures in the two chambers in response to external forces applied to the actuator piston and thereby the stiffness of the actuator.

Abstract: A system for controlling the wing sweep angle of the wings of an aircraft over their entire sweep range, including a detector for determining aircraft speed and altitude, a digital computer for receiving signals from the detector to produce output signals in response to the input signals therefrom, control apparatus responsive to signals from the computer, an actuator for moving the wings of the aircraft in response to the control apparatus, and a cross-shaft for synchronizing the movement of the wings. A manual controller is also included for manual control of the actuator.