Abstract: A marine steering gear equipped with an emergency steering means which comprises an emergency directional control valve capable of replenishing hydraulic fluid or oil to a plurality of pressure chambers of an actuator for a hydraulic steering engine through check valves and stop valves, and a relief valve designed to set a desired charge pressure and installed in lines of oil to be supplied through the directional control valve, check valves, and stop valves so as to forcibly reduce the air volumes in the pressure chambers and thereby hold the rudder blade substantially in a hydraulically locked state.

Abstract: A marine steering arrangement which includes a hydraulic steering machine, variable discharge type pump units for actuating the hydraulic steering machine and power units for remotely manipulating the pump units. The power units are provided respectively in at least two channels which includes a spare channel. Additionally, a mechanical control for mechanically coupling the pump units to the power units to control the pump units and mechanically receive a feedback of an amount of steering done by the steering machine is provided in the at least two channels which include a spare channel. Further, there are hydraulic coupling/decoupling devices interposed in control force transmission systems in the mechanical control, each of which can be switched between a first state for transmitting a control force and a second state for not transmitting a control force.