SHIP WITH ITS SCREW PROPELLER MOUNTED ASTERN AND METHOD OF STEERING THAT SHIP

摘要

The hull has a draught at the rear end, corresponding to the normal position of the ship for deep-water operation, greater than the draught of the front end, the keel line thereof descending correspondingly front to rear. The central or middle draught corresponds to the design draught allowable for operation in shallow water. The hull has a system for trimming the fully laden ship employing stern and bow fuel tanks. For shallow water operation, the hull is lowered at the bow and raised correspondingly at the stern, by displacement of fuel from the stern tank to the bow tank, into a trim position in which the keel line extends parallel to the water line. This construction enables the screw to be optimized substantially independently of draught-imposed limitations and the screw can have a diameter greater by the amount of stern lift than fixedly mounted screws of conventional designs.