Dual redundant active/active brake-by-wire architecture

In combination with an aircraft, an apparatus for dual redundant control of hydraulically operated wheel braking for the aircraft, the aircraft having right and left main landing gear and center landing gear that can move between a retracted position and an actuated position, the right, left and center landing gears having a plurality of wheels and a corresponding plurality of wheel brakes for the plurality of wheels, and a plurality of brake pedals for controlling operation of braking of said plurality of said wheels, said apparatus comprising:

• a primary hydraulic system connected in fluid communication with said plurality of wheel brakes for providing hydraulic power for normal operation of said plurality of wheel brakes in a normal braking mode, said primary hydraulic system comprising a plurality of primary hydraulic fluid control channels and a plurality of secondary hydraulic fluid control channels, the primary and secondary hydraulic fluid control channels operating so that even if one of the primary hydraulic fluid control channels and one of the secondary hydraulic fluid control channels fail to apply pressure, braking will be lost to only a portion of the wheel brakes and the loss will be in a symmetrical pattern;
• a secondary hydraulic system connected in fluid communication with said plurality of wheel brakes for providing hydraulic power for operation of said plurality of wheel brakes in an alternate braking mode, said secondary hydraulic system providing dual redundant analog brake-by-wire control in the alternate braking mode for the right and left main and center landing gears of the aircraft, and said secondary hydraulic system comprising at least one primary hydraulic fluid control channel and at least one secondary hydraulic fluid control channel;
• a control unit for controlling brake pressure communicated to said wheel brakes through said primary and secondary hydraulic systems;
• and
• a monitor channel operatively connected to said primary and secondary hydraulic systems for detecting faults in said primary and secondary hydraulic systems and for selecting between the primary and secondary hydraulic systems for providing braking pressure.