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or winds from aft, the ship must be broken out from the side on which 

 there are fewer ice obstacles. 



The above applies when the icebreaker breaks out a ship with her 

 stern. In heavy ice conditions this method is not practical since when 

 going astern the ice is piled up under the counter and fouls the pro- 

 pellers. This condition may cause the engines, which are turning at 

 full speed, to stop suddenly. The same happens when a propeller gets 

 caught against a chunk of ice, which in turn presses on other chunks 

 of ice. Since the propeller is unable to overcome this obstacle, a 

 broken blade or loss of the entire propeller may result. Going astern 

 in heavy ice may also disable the icebreaker's rudder. Therefore, the 

 above method of breaking out ships should be employed only when 

 there is no danger of damage to the propeller and rudder, or when 

 there is no other solution. 



Another method of breaking out a stuck vessel is to approach on the 

 windward side, with the target angle of approach varying according 

 to the heaviness of the ice. Generally this will be about 155° or 205° 

 (135° or 225° if the ice is heavy). The icebreaker's stern should be 

 swung so that it is as close as possible to the stem of the other vessel 

 and directly ahead thereof when the movement is completed. Be- 

 tween the icebreaker's stern and the beset vessel's stem there will in- 

 evitably be a floe fragment, which may be cracked by backing down 

 on it. As soon as backing is commenced, the beset vessel should be 

 instructed to go ahead with all possible speed consistent with safety. 

 This will keep her bow into the propeller wash as the icebreaker's 

 engines are turned ahead after the floe is cracked. It is advisable for 

 the escorting icebreaker to have a pudding over the sheer of her stem 

 since she may frequently be called upon to push the bow of the escort 

 around. In this event it may be necessary to break the ice on the 

 quarter toward which her stern will swing to minimize possibility of 

 damage to rudder and propellers. 



Ships can also be broken out by the icebreaker making complete 

 bow turns. This takes a great deal of time as the icebreaker first 

 turns toward the ship and then makes another turn astern of the ship. 

 On making the turn toward the ship, the icebreaker approaches her on 

 the lee side and passes along her close aboard. Astern of the ship the 

 icebreaker turns again to the original course. Moving ahead the 

 second time along the ship's side, thinning out the ice, she at the same 

 time signals the ship to follow. The heavier the ice, the more time 

 is required by this method, but in exceptionally heavy ice this is the 

 only suitable way of freeing vessels. Objection is sometimes made 



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