A suspension system for a vessel with at least one left hull, at least one right hull and a chassis, the suspension system including respective front left, front right, back left and back right support rams connected between the chassis and the respective hull and including a respective compression chamber which with a respective diagonal conduit forms a respective support compression volume; first digonal support interconnection valve (59) selectively interconnects front left and back right diagonal conduits (61, 64) and support compression volumes second diagonal support interconnection valve (60) selectively interconnects front right and back left diagonal conduits (62, 63) and support compression volumes, a deck attitude control system (100) comprising a controller (102), sensors, first and second diagonal actuating arrangements (25, 26) for controlling fluid flow across the respective diagonal support interconnection valve to control a position of a point on the chassis relative to a reference (5).

A water-air interface vehicle suitable for concealed navigation. A gybing box is arranged in a hull and includes a gybing motor, a gear train, a worm wheel and worm mechanism and a base; the worm wheel and worm mechanism are connected with a shaft of the gybing motor by the gear train; the base is connected with the worm wheel and worm mechanism; the transformable sail is fixed to the base; the gybing box is connected with a reefing mechanism; the gybing box operates the transformable sail in a set attack angle range or rotates 90 degrees according to a signal sent by a control system.

A suspension system for a vessel (1) having at least one left hull (11), at least one right hull (12) and a chassis portion (10), the suspension system including supports (20) for at least partially supporting the chassis portion relative to the left and right hulls, and a front left and back left damping ram (31, 33) connected between the chassis portion and longitudinally spaced points on the at least one left hull, afront right and back right damping ram (32, 34) connected between the chassis portion and longitudinally spaced points on the at least one right hull. The suspension system further includes a deck attitude control system (250) comprising a controller (252), sensors, and a respective actuator arrangement for each of at least two orthogonally spaced damper rams. The actuators control a position of at least one point on the chassis relative to at least one reference.

A workboat is disclosed comprising: a hull; a first pontoon attached to a first side of the hull; a second pontoon attached to a second side of the hull; a deck on an upper surface of the hull; a pontoon stowage system configured to deploy the first pontoon and second pontoon from a stowed position atop the deck to a deployed position extending outward from the hull; an actuator operatively connected to the pontoons and configured to actuate the movement between the stowed position and the deployed position; a control unit operatively connected to the actuator to regulate the deployment and stowage of the pontoons; and an operator interface for controlling the operation of the pontoon stowage system.