<P> The first submarine that did not rely on human power for propulsion was the French Navy submarine Plongeur, launched in 1863, and equipped with a reciprocating engine using compressed air from 23 tanks at 180 psi . In practice, the submarine was virtually unmanageable underwater, with very poor speed and maneouverability . </P> <P> The first air independent and combustion powered submarine was the Ictineo II, designed by Narcís Monturiol . Originally launched in 1864 as a human - powered vessel, propelled by 16 men, it was converted to peroxide propulsion and steam in 1867 . The 14 meters (46 feet) craft was designed for a crew of two, could dive to 30 metres (98 feet), and demonstrated dives of two hours . On the surface, it ran on a steam engine, but underwater such an engine would quickly consume the submarine's oxygen . To solve this problem, Monturiol invented an air - independent propulsion system . As the air - independent power system drove the screw, the chemical process driving it also released oxygen into the hull for the crew and an auxiliary steam engine . Apart from being mechanically powered, Monturiol's pioneering double hulled vessels also solved pressure, buoyancy, stability, diving and ascending problems that had bedeviled earlier designs . </P> <P> The submarine became a potentially viable weapon with the development of the first practical self - propelled torpedoes . The Whitehead torpedo was the first such weapon, and was designed in 1866 by British engineer Robert Whitehead . His' mine ship' was an 11 - foot long, 14 - inch diameter torpedo propelled by compressed air and carried an explosive warhead . The device had a speed of 7 knots (13 km / h) and could hit a target 700 yards (640 m) away . Many naval services procured the Whitehead torpedo during the 1870s and it first proved itself in combat during the Russo - Turkish War when, on January 16, 1878, the Turkish ship Intibah was sunk by Russian torpedo boats carrying Whiteheads . </P> <P> During the 1870s and 1880s, the basic contours of the modern submarine began to emerge, through the inventions of the English inventor and curate, George Garrett, and his industrialist financier Thorsten Nordenfelt, and the Irish inventor John Philip Holland . </P>

Who invented the first submarine used in war