| 摘要 |
A propulsion system for a water craft has at least one shaft (1) extending rearwardly from the transom (2) of the hull (3) of the craft and a drive system (9, 10, 11) for driving the shaft(s). A surface piercing propeller (4) is mounted on the or each shaft (1), proximal to the trailing edge (7) of the hull, so that the proopeller(s) operate in the transom cavity created behind the hull, in use of the craft. The ratio (S/C) of the spacing (S) of the blades (6) to the blade chord (C) for the or each propeller (4) is at least 2.0 along substantially the whole length of the blades. The propulsion system has high operational efficiency particularly suited for high speed marine craft. |
