GERMAN ACOUSTIC TORPEDO

Guns, torpedoes, mines, bombs, missiles, ammunition, fire control, radars, and electronic warfare.
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aurora
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GERMAN ACOUSTIC TORPEDO

Post by aurora »

The Zaunköning (Wren) came into service during the autumn of 1943. Intended to be an escort-killer, it achieved some early minor success only to be countered by the allied Foxer noise-making decoy. It was scoring hits against escort and merchants to the end of the war though.

The weapon was designed to lock onto the loudest noise after a run of 400m from its launch. This often proved to be the U-boat itself and standard issue-orders were to dive immediately to depth of 60m after launch froma bow tube while a stern shot was to be followed by a complete silence in the boat. Two U-boats were almost certainly lost when hit by one of their own T5 torpedoes, U-972 in Dec 1943 and U-377 in Jan 1944.

Uboat commanders reported a number of torpedo strikes and recorded the sinking of nine commercial steamers and 12 escort ships after the battle. In fact only six merchant ships and three escort vessels, a destroyer, a frigate and a corvette were sunk. A total of 640 TVs were fired in combat, sinking 45 ships.
Quo Fata Vocant-Whither the Fates call

Jim
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aurora
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Re: GERMAN ACOUSTIC TORPEDO

Post by aurora »

The Foxer consisted of one or more 3,000 lb (1,360 kg) arrangements of hollow metal pipes with holes cut in them. These were towed through the water about 200 m (220 yd) behind the ship. The water rushing through the holes and the pipes banging together created cavitation noise, much greater than that coming from the ship's propeller. This worked because the German homing torpedoes were tuned to home in on the sound frequencies generated by cavitation, and to home in on the loudest cavitation sound.

The Germans U-boat crews called it the Kreissäge (circular saw) or Rattatelboje (rattle buoy), estimated the volume of noise generated by Foxer at 10 to 100 times greater than that generated by a ship.The limitations of the system were that it could not be towed faster than 14 knots (26 km/h) and because of the noise it effectively rendered the towing ship's sonar useless. The drums also wore out quickly and the sound could be heard underwater over a long distance giving away the position of the towing ship to U-boats searching for convoys.

Sourced from Wikipedia
Quo Fata Vocant-Whither the Fates call

Jim
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