U-BOAT PROBLEM

Evening Post, Volume XCIV, Issue 42, 18 August 1917, Page 7

U-BOAT PROBLEM

AMERICAN MILITARY EXPERTS'

OPINIONS

MEASURES BEING BETTERED,

Military experts at Washington say that not oniy is constant study gradually improving the offensive manoeuvres of warships against submarines, but it is constantly improving measures of defence for merchant vessels against them. The authorities (states the Springfield. Republican) think that the greatest advantage that submarine had in this war was that inadequate consideration had been given to its unusual characteristics as a targeit. The fire of navai guns was j developed ito attain power to pierce armour and range, but when the submarine came forth as the chief naval weapon of the Huns it was found that the velocity of the high-powered naval rifles, their length "of range and their armour-piercing quafiiies, were wasted. Infinite pains had been spent upon attaining accuracy of fire through range, finders and other inventions, and also through untiring effort year in and year out. Yet when it came to be a question of protecting merchant ships against submarines, which is now, of course, the chief naval problem of the war, this progress counted almost for naught. STUDYING NEW METHODS. i The ordnance experts are studying new methods, and in .doing this they are going back to old- practices, a thing which has occurred any number of .times during this war. In trench warfare a large number of types of weapons, which every ordnance expert had supposed to be abandoned for good, have been restored to use. So, too, in developing an effective fire against submarines as far as the defence of merchant vessels is concerned, the experts are seeking a method that will give them a. spreading fire. Thought is being given to the use of the old smooth-bore gun and to the development of ammunition that would resemble the old grape-shot fire more nearly than anything else. It lias been found that the great difficulty is in getting a range on the-submarine in the very few minutes it remains' on the surface. Time and again the press despatches report the case of a merchant ship firing at the periscope of a submarine as the U-boat was submerging and remaining uncertain as to just what damage the fire had done,. As a matter of fact, naval ordnance experts say ,-that when such shots are lauded in the water at the very spot where the periscope has just been seen to go down the chances are that the shot is not effective. Travelling at terrific speed, the projectiles of highpowered rifles almost invariably ricochet; that is to say, they will go into the water about a depth of a foot and then turn sharply upward, just as a flat stone will do when a boy "skips" it over the wate?. Consequently, if the submarine periscope has gone a foot under the surface it has probably missed the shell. SPREADING FIRE SOUGHT. A second difficulty in fire with such high-power guns is that, although you could get rapidity of fire, you only get a single projectile There is now an idea' that if, instead of this, a means can bo found to get a spreading fire, similar to that from a shotgun, the chances of making a hit are better. It is hoped to develop also a plunging fire so that the shot, instead of ricocheting, will drop into the water If such a fire can be obtained it is possible so to regulate the ammunition that it will explode at a given depth aFter it hits the water, or will explode upon contact with, the submarine's huH, It is thought that if a fire of this sort can be- developed a merchant ship woflla be able to poswibly cover with one shot a surface of 200ft, and have all the shells of this plunging fire immediately sink over the submarine. In that way there would be a chance of striking tho hull of the U-boal, which is its most vulnerable part. The Germans now protect the conning towers of their submarines with armour plate, so that it is by no means certain that a hit on the conning tower is f*tal to a submarine. Moreover, to take off the tip of the periscope is 1101 always fatal, although it might disable the submarine. The later types of submarines have two und three periscopes as a safeguard against such a shot. MERCHANT SHIP PROTECTION. The fact seems to be that the present guns on merchant ships were destined for other work than submarine defence, and that to increase their power of defence the problem will have to be approached from a new angle. - This does not at all mean, it is said, that the present guns on merchant ships are useless. The arming of merchant ships, it is officially stated, has proved the very best possible defence against submarines. For'one thing it forces the submarine to keep below the surface, which means that they can no longer sink merchant ships by gunfire the way they used to do, but must use torpedoes in practically every attack. It takes about six months to build a torpedo, and Germany, it is figured, cannot have an unlimited supply of materials for them. Moreover, a submarine cannot carry more than eight or twelve torpedoes on a cruise, so that whenever a submarine is compelled to use torpedoes instead of gunfire its efficiency is that much reduced. But the Allied Powers, it is held, will never remain satisfied merely to use the defensive armament on merchant vessels to keep the submarines below the surface. They are determined to make such armament as effective as possible in the actual destruction of submarines. Satisfactory results in that respect have-not yet been reached, and that is the problem on which naval ordnance experts are now working. When that problem is solved the losses of the Germans in submarines will increase and different results in the U-boat campajgn will be recorded.