| 摘要 |
<p>In order to increase the efficiency of the propeller and hence of the propulsion, the diameter of the propeller (5) arranged at the stern is increased to at least 1.2 or better still 1.5 times the draught at the stern of the vessel under ballast, so that in operation the propeller projects out below the keel line (3) of the ship. So that the ship can travel in harbours, harbour entrances, canals or similar waterways with limited depth, the propeller (5) is brought into an inoperative position, in which no part of the propeller projects beyond the keel line (3) of the vessel, and locked in this position. The ship is then preferably propelled by an auxiliary propulsion, for example a rotating thrustor (8) and also controlled with the aid of this. <IMAGE></p> |
