A landing gear controller (120) to control extension and retraction of a landing gear for an aircraft, the landing gear controller (120) configured to cause, during an aircraft take-off or landing procedure, a landing gear extension and retraction system (110) to perform only a first portion of a landing gear extension or retraction process, on the basis of a status of the aircraft and prior to receiving a command for the landing gear to be extended or retracted.

A landing gear controller (120) to control extension and retraction of a landing gear for an aircraft, the landing gear controller (120) configured to cause, during an aircraft take-off or landing procedure, a landing gear extension and retraction system (110) to perform only a first portion of a landing gear extension or retraction process, on the basis of a status of the aircraft and prior to receiving a command for the landing gear to be extended or retracted.

An aircraft actuation system is disclosed that includes a pair of cylinders, a piston movably disposed in each cylinder, and a roller train that extends between the pistons in the two cylinders. A portion of the roller train is disposed beyond the cylinders to engage a pinion. Movement of the pistons in the two cylinders in opposite directions produces a corresponding movement of the roller train to in turn rotate the pinion. The roller train may be maintained in compression between its two ends by fluid pressure exerted on a common face of each of the pistons in the two cylinders. The cylinders may be disposed in non-colinear relation, including in parallel relation to one another. A guide may be used to maintain rollers of the roller train in a proper orientation for entry into a space between an outer race and the pinion.

An aircraft actuation system is disclosed that includes a pair of cylinders, a piston movably disposed in each cylinder, and a roller train that extends between the pistons in the two cylinders. A portion of the roller train is disposed beyond the cylinders to engage a pinion. Movement of the pistons in the two cylinders in opposite directions produces a corresponding movement of the roller train to in turn rotate the pinion. The roller train may be maintained in compression between its two ends by fluid pressure exerted on a common face of each of the pistons in the two cylinders. The cylinders may be disposed in non-colinear relation, including in parallel relation to one another. A guide may be used to maintain rollers of the roller train in a proper orientation for entry into a space between an outer race and the pinion.

An aircraft landing gear actuation system which uses two separate actuation forces to retract aircraft landing gear is disclosed. One of the actuation forces may be provided by an actuator, such as a hydraulic actuator. Another of these actuation forces may be provided by a pressurized fluid that is directed into the actuator through a conduit that extends into a hollow interior of an actuator rod of the actuator. The pressurized fluid may be provided from a pressurized fluid source that contains a fixed volume of pressurized fluid. This pressurized fluid may exert a force on an actuator piston of the actuator or the actuator rod. The pressurized fluid may also be used to dampen the deployment of the landing gear.

An aircraft landing gear actuation system which uses two separate actuation forces to retract aircraft landing gear is disclosed. One of the actuation forces may be provided by an actuator, such as a hydraulic actuator. Another of these actuation forces may be provided by a pressurized fluid that is directed into the actuator through a conduit that extends into a hollow interior of an actuator rod of the actuator. The pressurized fluid may be provided from a pressurized fluid source that contains a fixed volume of pressurized fluid. This pressurized fluid may exert a force on an actuator piston of the actuator or the actuator rod. The pressurized fluid may also be used to dampen the deployment of the landing gear.

A landing gear lifting/lowering EHA system includes: a hydraulic actuator configured to lift and lower the leg of an aircraft; at least one electrically operated hydraulic pump; a hydraulic path; a pressure sensor attached to the hydraulic actuator or the hydraulic path and configured to output a measurement signal corresponding to hydraulic pressure; and a controller configured to output a control signal to the electrically operated hydraulic pump, wherein, when a state in which the hydraulic pressure exceeds a set pressure continues for a set time, the control unit stops the electrically operated hydraulic pump in operation and resumes the operation of the electrically operated hydraulic pump after the hydraulic pressure drops to or below a second set pressure after the electrically operated hydraulic pump is stopped.

A landing gear lifting/lowering EHA system includes: a hydraulic actuator configured to lift and lower the leg of an aircraft; at least one electrically operated hydraulic pump; a hydraulic path; a pressure sensor attached to the hydraulic actuator or the hydraulic path and configured to output a measurement signal corresponding to hydraulic pressure; and a controller configured to output a control signal to the electrically operated hydraulic pump, wherein, when a state in which the hydraulic pressure exceeds a set pressure continues for a set time, the control unit stops the electrically operated hydraulic pump in operation and resumes the operation of the electrically operated hydraulic pump after the hydraulic pressure drops to or below a second set pressure after the electrically operated hydraulic pump is stopped.

A torque link assembly may comprise an upper torque link, a lower torque link, and a torque link pin. The upper torque link may define an upper hydraulic fluid channel. The lower torque link may define a lower hydraulic fluid channel. The torque link pin may fluidly couple the upper hydraulic fluid channel to the lower hydraulic fluid channel.

A torque link assembly may comprise an upper torque link, a lower torque link, and a torque link pin. The upper torque link may define an upper hydraulic fluid channel. The lower torque link may define a lower hydraulic fluid channel. The torque link pin may fluidly couple the upper hydraulic fluid channel to the lower hydraulic fluid channel.