RODERANLEGGNING FOR SKEPP MED TVA BALANSERADE RODER

摘要

A rudder assembly for a ship having an upright keel plane and a drive for generating a screw race passing backwardly along the plane comprises a pair of like rudders lying in the race and pivotal about respective upright axes spaced symmetrically to opposite sides of the keel plane. Each rudder has a central plane lying parallel to the keel plane during normal straight forward travel of the ship and has a non-concave inner face turned toward the keel plane and an outer face formed by a convex front portion generally in front of the respective axis and a concave rear portion generally behind the respective axis. The rear portions diverge from the respective central planes by angles between 2 DEG and 10 DEG , and the inner face has a rear portion similarly forming an angle of between 2 DEG and 8 DEG with the respective central plane. These rudders may be controlled individually in order to stop and even reverse the ship with a continuously backwardly moving screw race. In addition a pair of such rudders may be provided on a twin-screw ship, one for each screw race.