CHAPTER 2 



SUBMARINES AND ANTISUBMARINE UNITS 



During World War II, submarines sent millions 

 of tons of shipping to the bottom. Early in the 

 war, England's lifelines were nearly strangled 

 by German submarines. American submarines 

 played a large role in the defeat of Japan by 

 sinking nearly all her merchant marine. Ob- 

 viously, the submarine is a potent weapon, 

 requiring equally effective counter measures. The 

 United States and Great Britain were successful 

 in developing equipment, weapons, and tactics 

 that enabled the destruction of the German sub- 

 marine force. Japan, however, never was able 

 to develop an effective defense against our 

 submarines. 



Since World War II the submerged endurance 

 of the submarine has become sufficient to cause 

 difficulty in locating it. The problem increases 

 as the submarine goes constantly faster, deeper, 

 and stays down longer. To cope with the modern 

 submarine, we now have better detection devices, 

 more modern weapons, and newer ships, but 

 the battle for supremacy is a never-ending one. 



THE SUBMARINE 



All Sonar Technicians are concerned with the 

 hunt for and destruction of enemy submai'ines. 

 It is of especial importance, therefore, that you 

 know the capabilities of enemy submarines, and 

 know them well. Innumerable questions will come 

 to you over a period of time or after a course 

 of events in antisubmarine warfare (ASW) opera- 

 tions: How fast can a submarine dive or turn? 

 How does the submarine use depth? What is the 

 submarine's top speed when submerged? Because 

 this text is unclassified, many of the answers 

 are of a general nature. In your studies, though, 

 you will learn many details about submarine 

 characteristics and tactics. Such Imowledge makes 

 it easier for you to detect submarines and hold 

 contact after detection. Most of this text concerns 

 our own submarines, but foreign navies usually 

 have submarines of comparable ability. 



HiSTORY AND DEVELOPMENT 



The first successful submarine was built in 

 1620 by Cornelius Van Drebel, a Dutch physician. 

 During repeated trials in the Thames River, he 

 maneuvered his craft successfully at depths of 

 12 to 15 feet beneath the surface. 



Various other European designers of that 

 time constructed submersible craft also, but 

 they failed to arouse the interest of any navy in 

 an age when the potentialities of submarine war- 

 fare were inconceivable. 



Most of the early craft were of wooden frames, 

 covered with greased leather or similar material, 

 and propelled by oars. Different methods of 

 submerging were thought of and some were even 

 tried. One inventor's design consisted of a number 

 of goatskin bags built into the hull, each connected 

 to an aperture in the bottom. He planned to sub- 

 merge the craft by filling the sldns with water, 

 and to surface it by forcing the water out of the 

 skins with a "twisting rod." Although his vessel 

 was never built, it seems that this design was 

 the first approach to the modern ballast tank. 

 Another inventor actually submerged his craft 

 by reducing its volume as a result of contracting 

 the sides through the use of hand vises. 



Ideas were plentiful, some of them fanciful 

 and grotesque, but some contained elements 

 capable of practical application. Lack of full 

 understanding of the physical and mechanical 

 principles involved, coupled with the well-nigh 

 universal conviction that underwater navigation 

 was impossible and of no practical value, kept 

 postponing the attempt to utilize a submarine in 

 naval warfare during the early period. 



A submarine was first used as an offensive 

 weapon during the American Revolutionary War. 

 The Turtle, a one-man submersible designed 

 by an American inventor named David Buslinell 

 and hand operated by a screw propeller, attempted 

 to sink a British man-of-war in New York Harbor. 

 The plan was to attach a charge of gunpowder to 

 the ship's bottom with screws and explode it with 



