An aircraft system is disclosed including a hydraulic actuator, an inlet line for supplying hydraulic fluid to the hydraulic actuator, an outlet line for removing hydraulic fluid from the hydraulic actuator, a first one-way valve configured to allow fluid flow along the inlet line in a direction toward the hydraulic actuator, and a second one-way valve configured to allow fluid flow along the outlet line in a direction away from the hydraulic actuator.

A hydraulic system for a brake release device has a pump device, a tank, a valve assembly and at least one working port, where the working port is connectable to the tank or the pump device via the valve assembly. The pump device is switchable between an operating mode and a shutdown mode, where the valve assembly connects the working port to the tank in the shutdown mode and the valve assembly is only hydraulically operable. A brake release device having such a hydraulic system is also disclosed.

Provided is a hydraulic supply device. A hydraulic supply device according to one aspect of the present invention includes a motor which is coupled to a modulator block, in which a path and a valve for adjusting a hydraulic braking pressure are provided, and which includes a stator and a rotor, a rotary shaft which is coupled to the rotor and performs a rotary motion along with the rotor, and a magnet assembly which is coupled to the rotary shaft and includes a magnet disposed to face a motor position sensor for measuring an amount of rotation of the rotary shaft, wherein the magnet assembly may include a shaft, which is coaxially and linearly connected to and rotated along with the rotary shaft and of which one end portion supports the magnet, and a tolerance ring which is mounted on an outer circumferential surface of the shaft and inserted into an installation groove formed in the rotary shaft to fasten the shaft to the rotary shaft, wherein a rotation restriction protrusion for restricting rotation of the tolerance ring around the shaft may be formed on the tolerance ring.

A hydraulic control unit is provided, including a hydraulic control apparatus with a bidirectional pressurization function, where the hydraulic control apparatus includes a second hydraulic chamber and a first hydraulic chamber. The second hydraulic chamber provides a braking force for a first group of wheel cylinders through a first brake line provided with a first control valve. The first hydraulic chamber provides a braking force for a second group of wheel cylinders through a second brake line provided with a second control valve.