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be fully aware of, and prepared for, such an eventuality. Icebreakers 

 with a stem indentation use this method of towing only in exceptional 

 circumstances, and when the shape of the piloted ship's stem is not 

 adapted for close towing. If collision between the icebreaker and 

 the tow is unavoidable, the former should go full ahead on her engines 

 so that her wash will throw the towed vessel's bow to one side and 

 make the blow a glancing one instead of a direct bow to stern collision. 

 This action is recommended in all cases (even when not towing) when 

 the ship astern creeps up on the icebreaker. 



When the ice pressure is great, the channel closes up immediately 

 astern of the icebreaker. In such circumstances, it is necessary to tow 

 the ship close under the icebreaker's stern. To do this, the stem of the 

 towed vessel is secured as close as possible to the indentation at the 

 icebreaker's stern by means of the towline. The winch, backed by 

 additional stoppers, is secured so that the tow cannot ease off. The 

 icebreaker and the tow move as one unit. Advance is possible in the 

 heaviest ice, as long as the icebreaker can use her engines. The control 

 of the icebreaker is, however, more difficult as the towed vessel tends 

 to act as an uncontrollable rudder. Wlien the icebreaker stops, it is 

 almost impossible to go astern, as the towed vessel's rudder will be 

 endangered. 



BREAKING OUT SHIPS 



If a ship fails to make headway in the ice, she must signal without 

 delay, "I am stuck in the ice." Upon receiving the signal, and if con- 

 ditions permit, the icebreaker signals the other ships to proceed on 

 the course without her. Then she returns to, and breaks out, the ice- 

 bound ship. 



Ships are broken out of the ice in various ways, the method depend- 

 ing on the condition of the ice. If the ship is stuck in comparatively 

 thin ice, the icebreaker, to save time, goes astern without turning, 

 keeping her bow on the original course, and passes the ship close to 

 one side. After coming alongside, the icebreaker backs as far as the 

 stern and then goes ahead, simultaneously signaling the ship to follow. 

 If this maneuver is performed at a distance of from 5 to 10 yards from 

 the ship's side, the vessel as a rule can follow the channel as the ice 

 astern of the icebreaker is considerably thinned out. 



The direction of the wind must be carefully noted, and for breaking 

 out, the lee side is chosen. If the icebreaker approaches to windward, 

 the ship is blown towards the unbroken ice, and even after being 

 broken out will be unable to move. When the icebreaker comes up 

 on the lee side, a certain weakening is observed even in heavy ice, and 



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