The Mother of the Submarine 



As a complete floating naval base, the submarine mother-ship is indis- 

 pensable in our submarine program because of our two long coast lines 



\S everyone knows, — and as Germany 

 /-\ long ago learned to her sorrow, — the 

 Strait of Dover has been planted 

 and re-planted with British mines until 

 it would be sheer suicide for a German 

 submarine to attempt to pass through. 

 In order to attack England's shipping, 

 German submarines have therefore been 

 compelled to travel all around the British 

 Isles. In making this tedious detour, a 

 great tax is laid upon the submarine's com- 

 paratively delicate machinery. And since 

 this journey must be made under the water 

 most of the way, an even greater strain 

 falls upon the crew. If the submarine and 

 its crew ever get back, both will be in dire 

 need of repairs. 



Here is where the mother-ship justifies 

 her name. On returning to its assigned 

 harbor and signaling by wireless to its 

 parent-ship, the submarine is immediately 

 taken in between the ship's steel hulls and 

 is finally sheltered in the tubular compart- 

 ment amidships. The compartment is 

 water-sealed and huge pumps on the 

 mother-ship are started forcing the water 

 out — thus converting the compartment, in 

 effect, into a wonderful floating drydock. 

 The submarine's crew are received by the 

 mother-ship and are accommodated in 

 extra cabins especially la'd aside for them. 

 Here they can sleep on real beds and take 

 their well-earned rest. 



Meanwhile, the lathes and forges are 

 busy fashioning new parts and the duplicate 

 submarine members carried by the mother- 

 ship are mounted in place of those worn 

 out or damaged. The duplicate mechan- 

 isms are stored mostly on the decks. The 

 heavy lathes, on the other hand, are mostly 

 below; not exactly below deck, however, 

 but more correctly, in between the two 

 walls of steel which together make up 

 each of the twin hulls. Occupying the re- 

 maining space between these steel walls 

 are ballast and fuel oil tanks, torpedo and 

 other stores. In here also, and in the 

 hull at the front of the tubular docking 

 compartment — which at this section looks 

 like the hull of any ordinary ship, are the 

 marine oil engines for driving- the ship. 

 The cast-steel propellers with which these 

 connect project backward, one from each 

 of the twin hulls. 



In a few days' time, the submarine is 

 completely overhauled, and her food and 

 fuel supplies are replenished. Those of 

 her original crew who are unable to stand 

 the strain of the next journey are relieved 

 by trained men on the mother-ship. When 

 the new submarine crew have taken their 

 places, the docking compartment is flooded, 

 the ballast tanks trim the ship further, and 

 the submarine takes to the sea again with 

 renewed strength. When we consider that 

 one ship can mother a flotilla of six sub- 

 marines, scheduling four on active duty, 

 one in reserve and one in repair, the stra- 

 tegic importance of this type of vessel in 

 the present war is evident. Without put- 

 ting back for new supplies, and without 

 touching her own supplies, she can re- 

 juvenate a complete flotilla four times! 



After a submarine has been on active 

 duty a number of months, she is likely to 

 develop a weakened hull, a fault which 

 cannot be detected by ordinary methods. 

 Here again the mother-ship is of prime 

 importance. She is specially equipped to 

 convert her tubular compartment into a 

 testing dock. Her powerful pumps will 

 force the water into the testing dock until 

 the conditions are simulated that exist 

 at the dizzy depth of two hundred feet 

 below the water's surface — a submarine 

 rarely dives down more than fifty! The 

 testing crew within the submarine are in 

 constant communication by telephone with 

 the men at the pumps. If any weakness 

 has developed, leaks will soon be noticeable, 

 and the water pressure can be relieved 

 before further damage results. These leaks, 

 and whatever other faults are found, are 

 noted and subsequently repaired. 



The last, but not the least important 

 function of the parent-ship, is that of a 

 salvage boat. If a submarine sinks within 

 reach of divers, a mother-ship will be 

 able to save her, provided she can be suffi- 

 ciently protected from the enemy by friendly 

 warships or by her own quick-firing guns. 

 Mother-ships have a cruising radius of 

 four thousand miles and they can speed 

 towards the place of disaster at the rate of 

 ten knots. Expert divers are ready to 

 wrap a cable around the sunken submarine, 

 and powerful cranes are made ready to 

 haul it up. 



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