Abstract: A thruster for propelling a marine vessel, the apparatus comprising an upper housing, a lower housing, the lower housing being arranged to rotate relative to the upper housing, a first body arranged within the upper housing, the first body comprising a first inductor to provide a magnetic field, and a second body arranged within the lower housing, the second body comprising a second inductor to generate an electrical current from the magnetic field.

Abstract: A system for contactless power transmission in an azimuth thruster, the system comprising a first body (76) comprising at least one first inductor to provide a magnetic field, a second body (78) comprising at least one second inductor to generate an electrical current from the magnetic field, the bodies being configured to be relatively rotatable, the at least one first inductor and the at least one second inductor being configured to generate an electrical current from the magnetic field at all relative rotational positions, wherein the or each of the first inductors are tuned to resonate within a predetermined frequency band and the or each of the second inductors are tuned to resonate within a predetermined frequency band, the frequency band of the or each of the second inductors at least partially overlapping with the frequency band of the or each of the first inductors.

Abstract: A method for disassembling and/or assembling an underwater section of a retractable thruster unit of a swimming vessel. A supporting cradle is detachably fixed to the underwater section from below, and the thruster unit is lifted so that the underwater section is at least partly brought inside the well formed in the bottom of the vessel. Lifting wires of an auxiliary lift are connected to the supporting cradle for supporting the thruster unit. Water is drained from the well, and the lower gear is disengaged and the intermediate section and the lower gear are sealed. After that water is let to ingress into the well and the underwater section is lowered down by the auxiliary lift to dock bottom or sea bed, from where the underwater section is picked up with a crane.