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 SUBMARINES 



In 1931, Sir Hubert Wilkins published a book advocating the use 

 of submarines in ice exploration, advancing the argument that a sub- 

 marine could dive under ice that was impenetrable by the strongest 

 icebreaker, and that even the densest Arctic pack contained leads in 

 which a submarine could safely surface. He obtained an obsolete 

 United States submarine, the Nautilus^ in which he navigated to the 

 edge of the pack near Svalbard in September 1931. At this point 

 it was discovered that the diving rudders of the Nautilus had been lost, 

 so that it was impossible to continue under the ice and test the prac- 

 ticability of the submarine for ice navigation. The experiment with 

 the Nautilus has not been repeated by a civilian explorer. 



In 1944 a German submarine navigated under the Northeast Green- 

 land Pack, surfaced inside, and fired two torpedoes at the U. S. C. G. C. 

 Northwind. The submarine escaped by submerging and running 

 beneath the pack. 



LST's 



LST's may be used for transporting and unloading cargo in the 

 polar regions with the assistance of LVT's carried along. To 

 strengthen LST's in order to improve their serviceability in ice, 

 Douglas fir wood sheathing 5% inches thick should be installed from 

 the turn of the bow forward and covered with i/o-inch steel plate. 

 Sheathing abaft the turn of the bow may be omitted. The bow doors 

 should have i^-inch steel plate quilted over the wood sheathing men- 

 tioned above. Bracing timbers should be fitted between the bow 

 doors and hull adjacent to bottom of ramp. The flaps on the bow 

 doors should be welded shut and otherwise made an integral part of 

 the door. The bottom plating in the way of the bow voids should 

 be strengthened to prevent possible rupture from below. The hull 

 forward of the propeller guards should also be strengthened to prevent 

 puncture when the stern swings into ice. 



In an experiment with two LST's on an expedition to Barter Island, 

 a steel propeller was fitted to one shaft of each and the usual bronze 

 propeller left on the other shaft for comparative purposes. It was 

 found after the voyage that, except for minor pitting, the steel pro- 

 pellers were in almost new condition whereas the bronze propellers 

 on both ships were bent. 



An LST, even though specially strengthened, is not a suitable vessel 

 to absorb the punishment entailed in following an icebreaker through 

 the heavy, close pack of the type encountered between Point Barrow 



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