Vertically sided hull icebreaker ship - has barbed parts on wide angle central keel to break ice

The sides of the hull are vertical in a section which extends downwards from the water line to below the lower edge of the unbroken ice. The connecting ships bottom (18) extends in a V-shape to the central keel (19). Side mounted propellers (20) are positioned on both sides of the central keel. The immersion depth necessary for the ice to be broken may be adjusted by flooding or emptying ballast water tanks (30) in the ship (10). The propellers may be moved to below the ice, remaining on either side of the ship, for complete displacement of the ice floes situated under the ships bottom in the region of the ships bow (11).