Abstract: A hydraulic system for an aircraft includes a brake operation device, a pressure supply, a reservoir, a shut-off valve, and a wheel brake. The shut-off valve is in fluid communication with and is disposed between the pressure supply and the brake valve. The shut-off valve can include a poppet, a first valve seat and a second valve seat. Movement of the poppet is controlled by operation of the brake operation device. The poppet is movable between a first position where the poppet acts against the first valve seat and a second position where the poppet acts against the second valve seat. In the first position, fluid flow is blocked between the pressure supply and the brake valve through the shut-off valve. In the second position, fluid flow is allowed between the pressure supply and the brake valve through the shut-off valve. The wheel brake is in fluid communication with and downstream from the shut-off valve.

Abstract: A hydraulic system for an aircraft includes a master cylinder, a wheel brake, a pressure supply, a reservoir, and a shut-off valve in communication with the master cylinder, the wheel brake, the pressure supply and the reservoir. The shut-off valve can include a seal that is configured to preclude fluid flow between the pressure supply and the reservoir through the valve. The shut-off valve can be operable in a first position which blocks fluid flow between the pressure supply and the wheel brake through the valve and a second position which allows fluid flow between the pressure supply and the wheel brake through the valve. Fluid pressure from the master cylinder can control operation of the valve between the first position and the second position. Failure of the seal can result in fluid flow from the brake pressure supply toward the master cylinder.

Abstract: A hydraulic system for an aircraft includes a brake operation device, a pressure supply, a reservoir, a shut-off valve, and a wheel brake. The shut-off valve is in fluid communication with and is disposed between the pressure supply and the brake valve. The shut-off valve can include a poppet, a first valve seat and a second valve seat. Movement of the poppet is controlled by operation of the brake operation device. The poppet is movable between a first position where the poppet acts against the first valve seat and a second position where the poppet acts against the second valve seat. In the first position, fluid flow is blocked between the pressure supply and the brake valve through the shut-off valve. In the second position, fluid flow is allowed between the pressure supply and the brake valve through the shut-off valve. The wheel brake is in fluid communication with and downstream from the shut-off valve.

Abstract: A hydraulic system for an aircraft includes a master cylinder, a wheel brake, a pressure supply, a reservoir, and a shut-off valve in communication with the master cylinder, the wheel brake, the pressure supply and the reservoir. The shut-off valve can include a seal that is configured to preclude fluid flow between the pressure supply and the reservoir through the valve. The shut-off valve can be operable in a first position which blocks fluid flow between the pressure supply and the wheel brake through the valve and a second position which allows fluid flow between the pressure supply and the wheel brake through the valve. Fluid pressure from the master cylinder can control operation of the valve between the first position and the second position. Failure of the seal can result in fluid flow from the brake pressure supply toward the master cylinder.