ASDIC
By an electronic device called 'sonar' .
Sonar
During WWI, Germany had the biggest fleet of submarines and it was known and feared for its sneaky torpedo attacks on enemy ships.
They were used by submarines to navigate when not in open waters, They were also used by submarines and anti-submarine ships to locate enemy submarines.
During WW 1, submarines played a major part of a major war for the first time. The role of a submarine was basically to use torpedoes to sink enemy warships and cargo vessels.
Submarines are built with a special design that allows them to be faster underwater. Submarines can be used during a war as a way to sneak up to enemy lines in the water, but still stay hidden.
Periscopes were used to watch and observe and spy on the enemy lines during the war and are still used in submarines
Periscopes were used to watch and observe and spy on the enemy lines during the war and are still used in submarines
The role of submarines during the second world war was primarily the destruction of enemy commerce, and occasionally heavy naval units such as battleships, cruisers, and aircraft carriers. Since the battle of the atlantic was fought primarily against German Submarines which were targeting Allied merchant vessels, there would have been very little point to using submarines.
it was used to blow up enemy submarines and carry drugs into space
Ships would form a convoy in an attempt to reduce their vulnerability to enemy submarines.
There are now 'Attack' submarines who's main purpose is to sink enemy submarines and ships and also Missile submarines whose main purpose is to launch ballistic missiles at the enemy.