G7es torpedo

The G7es or Zaunkönig T-5 ("wren" in German) was a torpedo employed by German U-boats during World War II. It was known as the GNAT (German Navy Acoustic Torpedo) to the British. The torpedo was electric and had an effective range of 5700 meters at a speed of 24 knots (44 km/h). This torpedo employed acoustic, passive homing to find its target after a straight run of 400 meters. The 400 meter limit was employed for safety reasons, even though there were at least two instances of U-boats (U-972 in December 1943 and U-377 in January 1944) sinking after being hit by their own torpedo. This risk was later mitigated by requiring submarines to dive to 60 meters and go completely silent after launching acoustic torpedoes.

The first 80 T-5s were delivered on 1 August 1943, and the weapon was first used in September. A total of 640 were fired in combat, sinking 45 ships. The T-5 was countered by the introduction by the Allies of the "Foxer" noise maker.

The T-5 was nicknamed "Zerstörerknacker" (destroyer cracker) by the German submariners, as it was especially used against convoy escorts.

There were two main variants:
* A flat-nosed version which contained two sets of magnetostriction hydrophones.
* A round-nosed version which contained two magnetostriction hydrophones inside a funnel-shaped baffle.

External links

* [http://uboat.net/technical/torpedoes.htm A brief synopsis of German torpedo evolution during WWII at uboat.net]
* [http://www.uboataces.com/torpedo-tv.shtml More indepth details of TV (G7es) Acoustic Homing Torpedo at uboataces.com]

References

* "Hellions of the Deep", Robert Gannon, ISBN 0-271-01508-X
* Padfield, Peter, War Beneath the Sea Submarine Conflict 1939-1945, Pimlico 1997. ISBN 0-7126-7381-4
* Valentin Pikool, a Soviet Novelist talked about G7es torpedo in one of his historic novels.