Abstract: The invention concerns a radial coupling with shoes, of a simple structure, eliable in operation, and which is engaged and disengaged without delay. The coupling comprises a body in which are provided several chambers. The chambers are connected by means of pipes with a source of pressurized fluid. The body is fixed on the axis of a winch. Movable pistons are disposed in each chamber and are loaded with return springs. Supports are disposed on each piston and each support carries a frictional covering.

Abstract: Apparatus is disclosed for temporarily disconnecting from the steering mechanism of a ship one of a plurality of rudders that is in a jammed condition. Each rudder shaft is connected with the steering mechanism via a piston-cylinder motor that is supplied with pressure fluid via a supply system including at least one one-way valve. A safety valve is provided in the system for de-pressurizing the motor to disconnect the tiller member from the rudder shaft when the rudder is jammed and the pivotal force applied to the rudder by the tiller member causes the pressure fluid in the system to exceed the value determined by the safety valve.