SUBMARINE TYPES

Evening Star, Issue 19775, 27 January 1928, Page 7

SUBMARINE TYPES

ARTICLE BY REAR-ADMIRAL MAGRUDER LIFE BENEATH THE WAVES Contributed to the ‘Saturday Evening Post,’ the following is an extract from one of the articles in question, the subject in this case being submarine types;— The modem submarine is neither more nor less than a diving torpedo bout. Its principal function is to carry the automobile torpedo within striking distance of an enemy. Its valuj Ilea in its invisibility, ite power to deliver an unseen attack, and the destructiveness of the torpedo. Its weakness is its vulnerability when on the surface and its inability to remain under the surface for long periods of time. Submarines of the present day may bo divided into two types. The large cruiser type that can accompany the fleet is usually called a fleet submarine. This type may be employed, as are cruisers, lor scouting*, operating against the enemy’s trade routes, laying mines before enemy ports, and harassing an enemy fleet with mines and torpedoes. Undoubtedly vessels of this type will soon be as large as 3,ODD tons. There is no great technical difficulty in designing submarines that could at the same lime carry mines, mount guns of bin calibre, and even several aircraft. The United States now has a submarine capable of carrying on© small ’plane. The second type of submarines, known generally as the first-line type, is smaller, averaging about 800 tons. Boats of this type are designed to operate near the coast line of their own countries or from bases, to prevent blockades, minor attacks, and for other purposes within the limitations of their size and speed. According to the latest information obtainable the United States lias, built ami building, nine submarines and fifty of the smaller or first-lino type; Great Britain thirteen of the fleet type and thirty-wo of the first line; Japan twenty-three of the fleet type and forty-five of the first line; France three of the fleet type and Ibrtv-two of the first line; Italy four of the fleet type and eighteen of tho first line. In addition, all nations have numbers of small submarines of obsolescent typos. Submarines of both these types vary in gun power and in speed. In the comparison of the submarine power of nations, tonnage is not the only factor. A nation with bases along the trade routes of the world may employ _ tho smaller type of submarine as effectively as (lie larger. A nation, however, that has no ‘bases must rely upon the larger type with a large radius of action. ' Let us consider first the fleet submarine—the advanced type known in the United Slates as the VI. It has 3 tonnage of approximately 2,000, and costs about 7,U0l),000dol to build. 1U motive power consists of four internal combustion engines of the Diesel type. Two of these arc about 2,000 horsepower two-cycle engines. The others are 1,000 horse-power four-cycle engines. When the vessel is submerged, electric motors which derive current from storage batteries take up the task of propelling it, for no internal combustion engine can operate under such conditions. The hulls of the vessel are made strong enough to withstand the pressure at a maximum depth of about 200 ft. Within that depth it is possible for them to lie on the bottom indefinitely. At slow speeds the VI can remain submerged for only about, forty-eight hours. Thou it is necessary to come to the surface and recharge the storage batteries. The length of tho VI is 300 ft. the beam 27ft, and the draft loft. The vessel boasts a. very large cruising radius at 12 knots, or nautical miles an hour,, and carries six torpedo tubes—four in. the how and two in the stem—as well as one Sin and two machine guns. On the surface its maximum speed is about 20 knots; submerged it is 10 knots. A vessel of this size and typo can accompany the battle, fleet on the high seas under all conditions of weather. The habitability of the type when submerged is such that the crew can remain down four days or more without; being seriously affected. Within the boat the air is purified by being passed by blowers through saline containers, which dispose of {he poisonous carbon dioxide. Jn addition, there are bottles of oxygon which may bo used when it is found necessary to keep the required amount of oxygen in (he air. At great depths tho pressure is kept normal. .Should there be air leaks, the pressure is reduced by compressing the air and discharging it overboard. There is, however, one effect always experienced during submergence. It is a feeling of drowsiness, a slowing down of mental and physical activity. A most uncomfortable feature is the hign temperature within the boats when in tropical waters. Under such conditions the air is kept in circulatUni by lans, and tho mental reaction to this practice gives fairly satisfactory results. For the further vomlort of the personnel comfortable hunks are provided for the crew and small staterooms for the officers. A told storage plant is installed, so that fresh provisions may bo carried on long cruises. Improvements in tho mechanical details have kept pace with the advance in living conditions. The Diesel engines are entirely reliable. Wireless communication has progressed to such an extent that a boat is seldom out of touch with its home base or with tho fleet. During the World War orders to and reports from the. German U-boats at sea were transmitted constantly, promptly, and accurately. A submarine of the VI type carries a captain with the rank of commander, an executive officer, two engineer officers, and others. Its crew of ninety includes engineers, torpedo men, electricians, and men of other ratings to handle the ship, man the guns, and similar details. Officers and men alike must be trained for submarine work. In the United States service this training is given at a large submarine base at New London, Connecticut. The course includes theoretical os well a* practical instruction. In former yean service on submarines was decidedly uncomfortable, but now the crews have all conveniences and escape the discomforts that at one lime made it difficult to secure volunteers for that service. Enlisted men who serve in submarines receive odol a month increased pay, and, in addition. Idol for every day or part of a day the vessel is submerged. ; As a result of all these advantages and of freedom from military and other drills, duty on the subraersihles is often sought. A vessel of Mich characteristics as the VI is designed to accompany the battle fleet at all times, and may have various strategic and tactical employment. Scouting, screening tho fleet, mine laying, attacking the enemy mal# fleet during a ma>or engagement, and following a defeated enemy nr protecting tho retreat of its own ships in case of defeat—these are some of the duties it may perforin. Another use may bo cruiser warfare 1 against enemy merchant shipping. The cruiser submarine is capable of exercising the right to visit and search in the manner laid down by international law as applicable to surface vessels. It should be remembered, however, that unrestricted submarine warfare against merchant vessels was outlawed by the Washington Limitation of Naval Armament Conference. '