which is the first nuclear submarine to be designed and built in india
Arihant-class submarine The Arihant-class submarines are nuclear powered ballistic missile submarines built under the Advanced Technology Vessel (ATV) project.[21][22][23][24][25][26] They will be the first nuclear submarines designed and built by India.[27] The submarines are 112 m (367 ft) long with a beam of 11 m (36 ft), a draught of 10 m (33 ft), displacement of 6,000 tonnes (5,900 long tons; 6,600 short tons) and a diving depth of 300 m (980 ft). The complement is about 95, including officers and sailors.[28] The boats are powered by a single seven blade propeller powered by an 83 MW (111,000 hp) pressurised water reactor and can achieve a maximum speed of 12–15 knots (22–28 km/h) when surfaced and 24 knots (44 km/h) when submerged.[28]
History of submarines The first military submarine was Turtle in 1776. During the American Revolutionary War, Turtle (operated by Sgt. Ezra Lee, Continental Army) tried and failed to sink a British warship, HMS Eagle (flagship of the blockaders) in New York harbor on September 7, 1776. There is no record of any attack in the ships' logs.