Page:Popular Science Monthly Volume 90.djvu/659

 PojDuIar Science Monthly

��Vol. 90 No. 5

��239 Fourth Avenue, New York City

May, 1917

��$1.50 Annually

��Foiling Torpedoes with Whirling Plates

Hundreds of disks, rapidly rotated, are dropped into the water to act as an impenetrable steel wall

By John B. Flowers, E.E.. U. S. Navy

��ALTHOUGH hundreds of ships have been sunk by submarines since the war began, practically nothing has been done toward thwarting the torpedo. To be sure, huge nets of steel or of rope have been adopted for the protection of battle- ships in some navies, but they are of use only when the vessel is anchored. When a ship is under way, they produce an enor- mous retarding effect. At speeds of six knots and more, they are literally torn off. I n vestigations which I have con- ducted in an experi- mental tank of great dimensions have con- vinced me that it is feasible to protect ships from torpedo attack by means of rapidly rotating disks of steel. If a flat disk spins fast enough, its centrifu- gal force will keep it in one plane. These disks are made up of a metal and a wood plate screwed together so they Pink very, very slowh-. Another kind of disk

���John B. Flowers, the inventor of the whirling plate system for foiling torpedoes

��fVATE 5nNNIN& AT 1910 RtVOLUTIONS PER MINUTt

��«80 LBS AIR THRUST

���ORWING PULLtY SPINNING AT 3600 RTVOLUTIONS PtR rllNUTt

��How the disks launching gun.

��is all steel with a hol- low air-filled interior. This also sinks ver^-, ver>- slowly. Either kind may be used. If, then, it were possible to pour over the side of a vessel a large number of whirling disks or plates, they would remain suffi- ciently long in posi- tion to constitute a protecting wall against a torpedo. My steel disks are two inches thick and two feet in diameter. They are built up of one thirty^-pound plate and tsvo thin cover plates, which when welded together leave the disk hollow. Forty disks are placed in the magazine of each gun of a launch- ing battery. They are fed one by one towards the rect- angular barrel of the gun by a column of compressed air. When nearing the top, a disk is caught b>- three rotating rollers which are re- volved by an elec- tric motor. A speed of no less than two thousand revolutions per minute is thus given the disk, and the

��DISCHARGE PLATE

��are revolved and shot out of the There are forty disks to each gun

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