German Navy torpedo type G7A at the Norwegian Armed Forces Museum in Oslo
(photo by MoRsE)
U-Boats carried two different types of torpedoes.
- G7a: powered by compressed air, which left the trail of bubbles, a popular scene in movies.
- G7e: electrically powered torpedoes, which didn’t leave a trail of bubbles.
Improved versions of these torpedoes were issued to the U-Boat fleet in mid-1942. Subsequently torpedoes which homed in on the sounds made by a ship’s propellers was introduced. The Allies quickly came up with counter measures.
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