THE FUTURE OF THE SUBMARINE

New Zealand Tablet, 26 November 1914, Page 13

THE FUTURE OF THE SUBMARINE

Our intention in discussing this matter is not so much to consider the tactical qualities, but to regard the problem of the future potentialities of the sub-marine-boat from a mechanical standpoint (says lEngineering'). Until such craft are made more powerful, are given a higher speed, and have a much greater radius of action, their successes must be limited, even in attacking vessels in harbor, particularly in the presence of the latest system of submarine defence. All of these qualities call for increased dimensions, which increase their cost and reduce their handiness, especially in harbors and comparatively shallow waters. That progress is being made in the design of submarine-boats to attain the advantages desiderated is undoubted. The British Admiralty are fully alive to the possibilities of this new type of craft. They are vigilant in their study of progress in other navies, and are acting with enterprise in the encouragement of developments, particularly in respect of propelling machinery and tordesign. The interests of the nation preclude us from giving information regarding the latest British experimental vessels, but it may be said that in the one case the size exceeds that of any submarine-boat yet ordered, and that in the other case the aim is for higher speed. When these two vessels are completed their trials will disclose to the technical officers of the Admiralty the lines along which further developments may be made. First, in regard to size, it may be said that the largest of the German boats nearing completion has a displacement on the surface of 750 metric tons, and submerged of 900 tons, the length being just over 214 feet. It is propelled by two sets of Diesel engines, together of 4000 brake horse-power, working twin screws, and it is anticipated that the speed on the surface will be about 20 knots, and submerged about 10 knots, Russia is undei’stood to be building a vessel of considerably over 1000 tons, and proposals for ships of as much as 1700 and 2000 tons displacement are being considered by other Powers. These larger vessels will be able, of course, to carry a greater offensive armament, either by increasing the number of torpedoes, or by fitting larger guns with disappearing carriages, for which cavities are formed in the deck. It is understood that, so far, only 12-pounder guns are contemplated. If, however, four guns of 4in. calibre were adopted, the displacement would require to be increased while the adoption of Gin. guns would necessitate an increase in displacement of 18 per cent, over the vessel with 12-pounder guns. Increase in size, too, demands greater power, even if the speed be constant, and the aim is to get still higher speeds. So far practically all the modern submarines are propelled by heavy oilengines, and little difficulty may be experienced in supplying to a submarine-boat engines of 4000 or 6000 horse-power without increasing to any appreciable extent the size of the individual cylinder. Moreover, progress has undoubtedly been made in the reliability of -engines with cylinders of much higher power, and one may anticipate in the early future cylinders of 1000 horse-power. No trouble need be anticipated on this score excepting that the size of the ship must go on increasing if higher speeds are desired than are at present anticipated. There is, however, a growing disposition to experiment with steam-turbines in submarine-boats.