GB855993A - Control apparatus for aircraft - Google Patents

Abstract

855,993. Controlling aircraft. SPERRY GYROSCOPE CO. Ltd. Oct. 31, 1958 [Nov. 22, 1957], No. 36499/57. Class 4. [Also in Group XXIX] Control apparatus for an aircraft having a control surface formed as a set of independent sections movable in unison to apply torque about a control axis, one or more sections being movable by a manual controller, includes one or more main actuators each connected to move one section, an instrument detecting angular movement of the aircraft about the control axis, and means responsive, during manual control, to the output signal from the instrument, to control one or more, but not all, of the main actuators to cause control surface section movement to oppose the detected angular movement. In the Figure, the two sections 11, 12, of the surface are controlled by actuators 13, 14 thesmelves controlled by valves 15, 16 adjustable by the output rods 22, 23 of differential levers 20, 21, each having one input from a mechanical follow up feed back rod 24, 25 and another input from a manual controller 17. Movement of the manual controller thus effects corresponding movement in unison of sections 11, 12. A further input displacement to valve 16 is provided through an auxiliary differential lever 27 in rod 23, and an actuator 26 energized by an autopilot 18 detecting short term oscillations of the aircraft about the control axis. The actuator 26 may also be energized in accordance with angular movement. rate of movement, or acceleration about the control axis. The surface section 12 alone will be moved to correct these oscillations. The surface may comprise further sections, each actuated by the manual controller through a differential lever and main actuator, similarly to section 11. There may also be a section 28 actuated, like section 12, either by the manual controller or by the autopilot 18 or a duplicate autopilot. In this case, a comparator 31 compares the two actuator valve displacements, and gives a warning if a discrepancy of more than a predetermined magnitude occurs. The signals from the autopilot may be limited in magnitude. Such control systems may be applied to two or all three of the aircraft principal axes. Specification 828,785 is referred to.