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Submarines were sometimes referred to as submersibles.
The submarines were either called "submarines" or "U-boats." The German submarine was called the "U-boat"
German submarines were referred to as U-boats during the world wars.
The British lost 76 submarines during WWII.
During World War 2, it is reported that over 2,000 variants of Japanese Submarines were used during World War 2. Out of this, it is estimated that 10,000s were likely to be used during WW2.
Germany called there submarines U boats
The early SS and the newer GATO Class diesel submarines.
the U boats..
Britain, France, Germany, Italy and USA all used submarines during WW1
During WWI, Germany had the biggest fleet of submarines and it was known and feared for its sneaky torpedo attacks on enemy ships.
More than you can afford
ASDIC