Nuclear Submarines

The most revolutionary development in the science of underwater navigation was the application of nuclear energy to submarine propulsion. The first nuclear-powered submarine, the USS Nautilus, was launched in 1954 and commissioned the following year. In a trial run conducted in 1955, the Nautilus sailed totally submerged from New London, Connecticut, to San Juan, Puerto Rico-a distance of 2,170 km (1,350 mi) in 84 hours. Its cruising speed submerged was more than 20 knots for an almost unlimited range. Early in August 1958 the Nautilus made the first undersea transit of the North Pole, cruising under the polar ice pack from Point Barrow, Alaska, to a point between Spitsbergen, Norway, and Greenland.

The USS Skipjack, launched in 1956, combined nuclear propulsion with the blimpish hull form of the Albacore and a single propeller. Advanced versions of this submarine, known as the Thresher class, were placed in operation in the early 1960s. In 1963 the USS Thresher was lost, with 129 men on board, during deep-diving tests in the Atlantic. The tragedy prompted extensive investigation and resulted in innovations in submarine design and undersea rescue technology, making deep-sea exploration and diving safer ventures in the future. The United States has more than 100 submarines in operation, almost all of them nuclear-powered. Most are equipped with a nuclear reactor designed to provide propulsion for at least 640,000 km (400,000 mi) without refuelling.