Anti-Submarine Warfare (ASW) techniques grew out of necessity during WWII. In the early days of the Battle of the Atlantic, German U-boats had a field day sinking supply ships bound for Britain. In time, as the U.S. joined the war, the escorted ship convoy system, along with aerial reconnaissance and later long-range bomber cover, eventually spelled the end of the U-boat threat. By the end of the war, German U-boats had suffered losses of 70% of boats and crew.
Allied warships also began carrying the first early forms of Sonar and Radar, which significantly improved submarine detection.
Convoys were used to destroy any U-boats that were in their way.
sonar
This can be used to blow up enemy ships (e.g E12)
The captain of the submarine raised the periscope to see if there's danger.
There are many different kinds of ships that can be used to find things underwater. You could use a submarine.
A periscope is used to observe the surface from a submarine
To prevent additional heart attacks, aspirin and an anticoagulant drug often follow the thrombolytic drug.
A U-Boat was a German submarine that was used to fire torpedoes at ships and spy on the Brits.
Before the war, people mainly used ships and boats, therefore, the people with the submarine could destroy these ships.
The first submarine used for military purposes was built in 1776 by David Bushnell (1742-1824) of the US. His "Turtle" was a one-man, wooden submarine powered by hand-turned propellers. It was used during the American Revolution against British warships. The Turtle would approach enemy ships partially submerged to attach explosives to the ships's hull. The Turtle worked well but the explosives did not.
Warships traveled with Merchant ships for protection.
Warships traveled with Merchant ships for protection.