Distributed trailing edge wing flap systems are described. An example wing flap system for an aircraft includes a flap and an actuator. The flap is movable between a deployed position and a retracted position relative to a fixed trailing edge of a wing of the aircraft. The actuator is to move the flap relative to the fixed trailing edge. The actuator is hydraulically drivable via first pressurized hydraulic fluid to be supplied by a hydraulic system of the aircraft. The actuator is also hydraulically drivable via second pressurized hydraulic fluid to be supplied by a local power unit. The local power unit is selectively connectable to an electrical system of the aircraft. The electrical system is to power the local power unit to supply the second pressurized hydraulic fluid.

A helicopter autopilot system includes an inner loop for attitude hold for the flight of the helicopter including a given level of redundancy applied to the inner loop. An outer loop is configured for providing a navigation function with respect to the flight of the helicopter including a different level of redundancy than the inner loop. An actuator provides a braking force on a linkage that serves to stabilize the flight of the helicopter during a power failure. The actuator is electromechanical and receives electrical drive signals to provide automatic flight control of the helicopter without requiring a hydraulic assistance system in the helicopter. The autopilot can operate the helicopter in a failed mode of the hydraulic assistance system. A number of flight modes are described with associated sensor inputs including rate based and true attitude modes.

A system of an aircraft includes a system pump and a booster pump. The system pump is configured to provide hydraulic fluid to the hydraulic system at a first working pressure. The booster pump is configured to supply hydraulic fluid to at least one boostable actuator at a second working pressure higher than the first working pressure. The boostable actuator is operatively coupled to and configured to actuate at least one flight control surface of an aircraft. The booster pump is configured as a high-pressure accumulator and an accumulator energizer, or as a hydraulic actuator pump and a variable speed motor.

A system of an aircraft includes a system pump and a booster pump. The system pump is configured to provide hydraulic fluid to the hydraulic system at a first working pressure. The booster pump is configured to supply hydraulic fluid to at least one boostable actuator at a second working pressure higher than the first working pressure. The boostable actuator is operatively coupled to and configured to actuate at least one flight control surface of an aircraft. The booster pump is configured as a high-pressure accumulator and an accumulator energizer, or as a hydraulic actuator pump and a variable speed motor.

A system for moving a hydraulic actuator that uses the new type of hydraulic no-back device. In some examples, the system comprises: a hydraulic power module for pumping hydraulic fluid through the system to the actuator, a reservoir for receiving said fluid back from said system and said actuator, first and second check valves; a conduit or conduits for fluidly connecting said power module to said check valves and said reservoir; and wherein said conduit or conduits are connected so as to allow said hydraulic fluid to flow from the hydraulic power module to said first check valve, and from said first check valve into said hydraulic actuator, and from said hydraulic actuator to said second check valve and from said second check valve to said reservoir.

A mode valve includes a spool axially moveable within a sleeve in response to a control (e.g. hydraulic or electro-mechanical) command. The spool includes channels and lands, and the sleeve comprising ports in fluid communication with a hydraulic fluid supply and ports in connection with control chambers of an actuator responsive to the valve. The valve also includes first drive means for moving the spool, relative to the sleeve, between a first position, and a second position in which fluid flow from the fluid supply to the actuator chambers through the valve is blocked and wherein a fluid path with a first pressure drop is defined in the mode valve for fluid flow between actuator chambers; the mode valve comprising second drive means for moving the spool relative to the sleeve to a third position in which fluid flow from the fluid supply to the actuator chambers is blocked.

A mode valve includes a spool axially moveable within a sleeve in response to a control (e.g. hydraulic or electro-mechanical) command. The spool includes channels and lands, and the sleeve comprising ports in fluid communication with a hydraulic fluid supply and ports in connection with control chambers of an actuator responsive to the valve. The valve also includes first drive means for moving the spool, relative to the sleeve, between a first position, and a second position in which fluid flow from the fluid supply to the actuator chambers through the valve is blocked and wherein a fluid path with a first pressure drop is defined in the mode valve for fluid flow between actuator chambers; the mode valve comprising second drive means for moving the spool relative to the sleeve to a third position in which fluid flow from the fluid supply to the actuator chambers is blocked.

An aircraft assembly, having: a reference component; a first component and a first actuator, the first actuator configured to move the first component relative to the reference component; a second component and a second actuator, the second actuator configured to move the second component relative to the reference component; a position sensor configured to measure a position of the first component, and to output a position value, the sensor being capable of outputting a plurality of non-zero position values; and a controller configured to control the movement of the second component by the second actuator based at least partially on the position value output by the position sensor

A system of an aircraft includes a system pump and a booster pump. The system pump is configured to provide hydraulic fluid to the hydraulic system at a first working pressure. The booster pump is configured to supply hydraulic fluid to at least one boostable actuator at a second working pressure higher than the first working pressure. The boostable actuator is operatively coupled to and configured to actuate at least one flight control surface of an aircraft. The booster pump is configured as a high-pressure accumulator and an accumulator energizer, or as a hydraulic actuator pump and a variable speed motor.

A system of an aircraft includes a system pump and a booster pump. The system pump is configured to provide hydraulic fluid to the hydraulic system at a first working pressure. The booster pump is configured to supply hydraulic fluid to at least one boostable actuator at a second working pressure higher than the first working pressure. The boostable actuator is operatively coupled to and configured to actuate at least one flight control surface of an aircraft. The booster pump is configured as a high-pressure accumulator and an accumulator energizer, or as a hydraulic actuator pump and a variable speed motor.