Nuclear-powered Ballistic Missile Submarines


From 1960 to 1966 the U.S. Navy launched a total of 41 boomers, called the "41 for Freedom." Every SSBN had two full crews, Blue and Gold, rotating at approximately 100-day intervals so that the ship might remain more continuously on patrol.

Each SSBN carried 16 Polaris nuclear missiles. Conversion to more accurate Poseidon missiles, starting in 1972, required only modification of the existing SSBNs. And even more advanced Trident I missiles, from 1979 onward, could be accommodated on the last 12 of the original 41 SSBNs.

The first of the much larger Ohio-class boats, which entered service in 1981, was designed specifically for the new and much larger Trident II missiles. Until Trident II became available in 1990, however, the new submarines were equipped with Trident I. Well over twice the displacement of their predecessors, each of the 18 Ohio-class SSBNs carried 24 missiles.

View a cutaway of an Ohio-class boomer submarine.

USS George Washington (SSBN-598) Polaris Ballistic Missile Submarine
USS George Washington was America's first nuclear-powered boomer and the first of a five-ship class. Shipbuilders at Electric Boat Co. altered the design of an attack submarine then under construction to insert a 130-foot (40-m) long mid-section holding 16 launch tubes between the sail and stern.

When completed, George Washington measured 382 feet (162 m) long and 33 feet (10 m) abeam, displacing 6,709 tons submerged. Her surface speed was 16 knots (30 km/hr), substantially slower than her submerged speed of 22 knots (41 km/hr). Commissioned at the end of 1959, George Washington went to sea on her first patrol in November 1960 with a crew of 112 and 16 Polaris A-1 ballistic missiles. Refitted with improved missiles, the Washington-class boats continued their patrols until the early 1980s.

USS Ohio (SSBN-726) Trident Ballistic Missile Submarine
Ohio's keel was laid in April 1976; she was launched three years later and commissioned in November 1981. The 18 Ohio-class boomers are the largest ever built by the United States: 560 feet (170 m) long and displacing 18,700 tons submerged, they carry a crew of 157.

The Ohio class was designed specifically to carry Trident II missiles, which are much larger than Poseidon or Trident I missiles. They also operate very quietly, powered by the S8G (Submarine, Model 8, General Electric) reactor plant.



Above, USS Robert E. Lee (SSBN-601), a George Washington-class boat commissioned in 1960, steams slowly past the Newport News docks. Courtesy Newport News Shipbuilding

USS John Marshall (SSBN-611), one of five Ethan Allan-class boats designed from the start for ballistic missiles, underwent sea trials in 1962. Courtesy Newport News Shipbuilding

Benjamin Franklin-class USS George Washington Carver (SSBN-656), launched in 1965, belonged to the 12-boat Benjamin Franklin-class, notable for their extremely quiet operation. Courtesy Newport News Shipbuilding

"41 for Freedom"
Submarine building proceeded at a furious pace in the early 1960s, as the United States strove to deploy a major component of its Strategic Triad. From 1960 to 1966 the U.S. Navy launched a total of 41 SSBNs, called the "41 for Freedom." All were named for eminent figures in American history and divided among the 5-ship George Washington class, the 5-ship Ethan Allen class, and the 31-ship Lafayette/Franklin class. Initially, each boat carried 16 Polaris nuclear missiles that could be launched underwater toward distant targets. Conversion to Poseidon missiles began in 1972. Further modification allowed Franklin-class boats to convert to Trident I missiles beginning in 1979. U.S. Navy poster

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