NAVIGATION OF SHIPS UNDER ICE CONDITIONS Russian patent published in 2001 - IPC

FIELD: shipbuilding navigation in arctic areas; building and operation of surface and submarine transport ships under ice conditions. SUBSTANCE: method includes motion of ships on surface, breaking ice cover from beneath of inclined taper surface of fore portion of ship and turning in course, if necessary, shifting rudder and breaking edge of ice channel from below due to wedge-shaped form of sides. In approaching ice blocks, ship's bow is sunken slightly by means of tanks increasing her draft and trim till complete submergence continuing motion in submerged position and rounding submerged portion of ice block at retained insignificant buoyancy continuing motion with deck sliding over slopes of ice fields. To facilitated turning in surface position, stern is slightly submerged ensuring its slippage at the moment of beginning of turn; trim is changed to bow due to control of ballast and edge of ice channel is broken from below. To enhanced ice breaking effect both at direct motion and in the course of turning, positive vibration of fore extremity is created by means of vibrating unit and compressed air is fed to fore or aft ballast tanks, after which it is bled. EFFECT: enhanced ice possibility of chip. 1 dwg