Aircraft Hydraulic System With A Dual Spool Valve And Methods Of Use

An assembly to position a flight control member of an aircraft, the assembly comprising:

• a hydraulic actuator operatively connected to the flight control member and comprising a piston, a first chamber on a first side of the piston, and a second chamber on a second side of the piston;
• a dual spool valve comprising first and second manifolds that each include a supply port to receive fluid from a supply line, a return port to move fluid to a return line, and an actuator port to move fluid to the actuator;
• and
• a first spool movably positioned in the first manifold and a second spool movably positioned in the second manifold, the first and second spools being independently movable between a first position and a second position;
• in the first position, the first and second spools blocking the supply ports to prevent hydraulic fluid from moving from the supply line to the actuator and being away from the return ports to allow hydraulic fluid to move from the actuator to the return line;
• in the second position, the first and second spools positioned away from the supply ports to allow hydraulic fluid to move from the supply line to the actuator and blocking the return ports to prevent hydraulic fluid from moving from the actuator to the return line;
• the first and second spools being positioned away from the actuator ports in each of the first and second positions to allow hydraulic fluid to flow into and out of the actuator.

A method of controlling a dual spool valve to control a hydraulic actuator and move a flight control member of an aircraft, the method comprising:

• positioning a first spool in a first manifold at a second position and opening a supply port in the first manifold and moving hydraulic fluid from a supply line and into a first chamber of a hydraulic actuator and positioning a second spool in a second manifold at a first position and opening a return port in the second manifold and moving hydraulic fluid from a second chamber of the hydraulic actuator to a return line and moving a piston of the hydraulic actuator in a first direction;
• positioning the first spool in the first manifold at a first position and opening a return port in the first manifold and positioning the second spool in the second manifold at the first position and opening the return port in the second manifold and moving hydraulic fluid from the first chamber of the hydraulic actuator through the return port in the first manifold and through the return port in the second manifold and into the second chamber of the hydraulic actuator and moving the piston of the hydraulic actuator in a second direction;
• positioning the first spool in the first manifold at the first position and opening the return port in the first manifold and moving hydraulic fluid from the first chamber to the return line and positioning the second spool in the second manifold to a second position and opening a supply port in the second manifold and moving hydraulic fluid from the supply line and into the second chamber of the hydraulic actuator and moving the piston of the hydraulic actuator in the second direction;
• and
• positioning the first spool in the first manifold at the first position and opening the return port in the first manifold and positioning the second spool in the second manifold to the first position and opening the return port in the second manifold and moving hydraulic fluid from the second chamber of the hydraulic actuator through the return port in the second manifold and through the return port in the first manifold and into the first chamber of the hydraulic actuator and moving the piston of the hydraulic actuator in the first direction.