What is proposed is a rotor with adjustable vanes, comprising a rotary structure rotating about a main axis and comprising a set of vanes rotating about a series of vane axes parallel to the main axis and defined by said rotary structure, and a mechanism associated with each vane and configured to control the variations in inclination of the associated vane according to the angular position of the rotary structure, this mechanism comprising a first element (65) supporting a pin (64) and a second element which is eccentric with respect to the first and configured to channel the movements of the pin along an imposed path.

According to the invention, said path is imposed by the translational movements of a carriage (62) along one or more guides (61) provided on the second element.

A marine propulsion unit including a rotary casing rotatable about a central axis A, and blades extending axially from the rotary casing for rotation with the rotary casing about the central axis A, wherein each blade is mounted for pivotal movement about blade axes B. A blade shaft portion of each blade is at least partly surrounded by a blade housing and by a blade portion of each blade is outside the blade housing, wherein the blade housing is releasable attached to the rotary casing, and each blade being supported in the blade housing by means of bearings for the pivotal movement.

A marine propulsion unit including a rotary casing rotatable about a central axis A, and blades extending axially from the rotary casing for rotation with the rotary casing about the central axis A, wherein each blade is mounted for pivotal movement about blade axes B. A blade shaft portion of each blade is at least partly surrounded by a blade housing and by a blade portion of each blade is outside the blade housing, wherein the blade housing is releasable attached to the rotary casing, and each blade being supported in the blade housing by means of bearings for the pivotal movement.

An arrangement is described includes a pressurised gas system and a cyclorotor located within an annular structure. The cyclorotor can be a propulsor for a marine vessel and includes a rotary housing spaced apart from the structure by an annular volume, and a plurality of blades extending from a surface of the rotary housing, each blade having a respective blade axis about which it can be pivoted relative to the rotary housing. The pressurised gas system includes a pressurised gas supply, one or more gas outlets in fluid communication with the annular volume, and a gas supply unit with a controller adapted to control the delivery of pressurised gas from the pressurised gas supply into the annular volume through the one or more gas outlets.