Submarines The first military submarines could only travel for short distances while underwater During World War I 1914 1918 submarines were made with sturdy double hulls an outer hull and an inner hull called a pressure hull The pressure hull had ballast tanks that could be filled with air or water to make them rise or sink To steer while diving underwater the subs used movable short wings at the stern or back called hydroplanes A conning tower also called a fin or sail helped to keep the submarine stable It housed sensors as well as periscopes for looking around and above objects Batteries powered the sub’s electric 4
motors while submerged By the end of World War II 1939 1945 submarines spent most of their time at the surface In the 1950s nuclear power allowed subs to stay underwater longer Modern submarines SSBNs have become large platforms for nuclear ballistic missiles Others called hunter-killers SSNs are designed to destroy SSBNs This Japanese Sōryū-class diesel-electric fast attack submarine uses Stirling engines These engines do not need air for pressure to help the sub remain submerged for long periods of time 5
The United States Civil War 1861 1865 Charleston’s outer harbor Early Submarines The first military submarine was built in 1720 by Russian carpenter Yefim Nikonov It looked like a giant wooden barrel Built for Russian Czar Peter the Great it was armed with flamethrowers Unfortunately it sank during its first trial in 1724 Many successful human-powered submarines were built around the world American inventor Robert Fulton made the Nautilus for the French Navy in 1800 Jose Rodriguez Lavandera created the 6
On February 17 1864 the Confederate States of America launched the Hunley on a mission to sink a warship the USS Housatonic The mission was successful but the Hunley sank before it could return to base All the crew were lost Hipopotamo for the Ecuadorian Navy in 1837 Neither was very successful The first submarine to successfully sink a ship was the H L Hunley This submarine used explosives attached to a wooden spar that was 22 feet 6 7 m long mounted on the Hunley’s bow Seven crew members turned a crank handle to power the propeller while one person steered The Turtle designed by David Bushnell was the first American military submarine It was built in 1775 and was used during the American Revolutionary War 1775 1783 7
