Submarine Warfare.

Mount Ida Chronicle, Volume XLV, Issue XLV, 15 June 1917, Page 3

Submarine Warfare.

Offensive and Defensive Poware. In answer to questions by a correspondent as to the method used by submarines in firing torpedoes, the Army anuWavy Journal says: "SBpbmarine fires her torpedo whon submerged. She fights warships only when submerged, but fights unarmed ships on, the surface with her gun, which has been of three and four-inch calibre, and will probably be increased to six inch. Submarinas, when about to fire a torpedo, usually submerge to about fifteen feet. The torpedo is always ejected into the sea from a sub-, merged tube, and the torpedo maintains a straight course at the desired depth until it hits its object. If the torpedo should be fired from a submerged tube, Bay at a greater depth than fifteen feet, and the latter was the depth decided for it, the torpedo rises to the desired level. A hydrostatic and pendulum gear forces the torpedo to travel at the desired level and at the set depth. A gyroscope makes the torpedo travel in a straight line in any given direction.

"Torpedoes are usually discharged at about 2000 yards, or just over the mile, and at a lesser distance if found expedient. The Whitehead torpedo maintains a speed of thirty-eight knots at 2000 yards, and a speed of forty-two knots at 1000 yards. The wake of the submarine periscope on a smooth sea can be picked up at 50,000 yds, and submarines cannot be discovered at more than about five miles. Thay have been known to approach a battleship within 500 yards in a cHoppy sea before being discovered.

"The most effective guns used against submarines are foar-incb, six-inch and six-pound rapid firers. The four-inch gun fires a shot weighing thirty-three pounds, and it can be fired very rapidly. It would be possible to fire fifteen shots a minute. The four-inch gun was fired so rapidly that five shots have been sailing through the air in a procession at the same time. A six-inch gun, with a. good crew, can fire about six aimed shots a minute. Another effective arm against' submarines is the six-pound rapid fire gun which has been fired at the late of twenty-two aimed shots per minute. These shots would go into the hull of a eubmarine at a distance of 3000 yards as easily as through pasteboard. The six pounder is considered one of the best defensive guna there is against submarines.

"The lowest depth to which a United States submarine is known to have submerged is 285 feet, but this is an unusual depth, and from 150 to 200 feet is the general requirement in submerging tests. The ordinary depth a submarine needs to submerge completely is about sixty feet* Some of the latest, types of submarines built for the United States are of 1200 tons displacement, and are 250 feet long. They have a radius of action of 8000 miles and surface speed of twenty knots and submerged speed of thirteen knots."