Ethan Allen-class submarine

Ethan Allen-class submarine. The Ethan Allen class was the second class of fleet ballistic missile submarines developed for the United States Navy, following the pioneering George Washington class. These vessels were the first SSBNs designed from the keel up for the strategic deterrence mission, carrying sixteen UGM-27 Polaris missiles. They played a critical role in the Cold War strategic nuclear triad and were involved in the only live nuclear test firing of a Submarine-launched ballistic missile.

Design and development

The design and development of the Ethan Allen class was a direct response to the evolving demands of the Cold War and the success of the converted George Washington class. Authorized under the leadership of Chief of Naval Operations Arleigh Burke, the class was the first purpose-built for the Polaris missile system, allowing for a more optimized internal layout compared to its predecessors. Key design improvements included a stronger pressure hull, enhanced sonar systems like the BQS-4, and greater habitability for the extended patrols required by the deterrence mission. The lead boat, USS Ethan Allen (SSBN-608), was constructed at General Dynamics Electric Boat in Groton, Connecticut, setting the standard for the subsequent units built at Mare Island Naval Shipyard and Newport News Shipbuilding.

Specifications

The Ethan Allen-class submarines had a length of 410 feet 4 inches and a beam of 33 feet, with a submerged displacement of nearly 8,000 tons. Propulsion was provided by a single S5W reactor, driving two steam turbines and enabling a submerged speed of 21 knots. Their primary armament consisted of sixteen UGM-27 Polaris A-2 and later A-3 missiles housed in launch tubes behind the sail. For self-defense, they were equipped with four 21-inch torpedo tubes in the bow, typically carrying Mark 37 or Mark 48 torpedoes. The class featured a test depth of 1,300 feet and carried a complement of 140 sailors, divided into alternating Blue and Gold crews to maximize operational availability.

Service history

The service history of the Ethan Allen class was defined by its central role in Operation Dominic and decades of strategic patrols. In 1962, USS Ethan Allen (SSBN-608) successfully launched a live Polaris A-2 armed with a W47 nuclear warhead over the Pacific Proving Grounds as part of test Frigate Bird, the only full test of the U.S. Submarine-launched ballistic missile system. Throughout the 1960s and 1970s, boats of the class conducted continuous deterrent patrols from bases like Holy Loch in Scotland and Apra Harbor in Guam, directly confronting the Soviet Navy. In the 1980s, under the SALT I treaty, they were disarmed of their ballistic missiles and four boats were redesignated as attack submarines (SSN), serving in roles such as Special forces support before final decommissioning by 1992.

Ships in class

Five submarines comprised the Ethan Allen class, all named for notable figures in American history. The lead boat was USS Ethan Allen (SSBN-608), followed by USS Sam Houston (SSBN-609), USS Thomas A. Edison (SSBN-610), USS John Marshall (SSBN-611), and USS Thomas Jefferson (SSBN-618). All were constructed between 1959 and 1963, with Thomas Jefferson being the final unit completed. Following their service as ballistic missile submarines, Sam Houston and John Marshall were converted to transport SEAL teams and other United States Special Operations Command forces, designated as "special operations" submarines during the 1980s.

See also

* George Washington-class submarine * Lafayette-class submarine * Ohio-class submarine * Polaris missile * Nuclear navy

Category:Submarine classes Category:Ballistic missile submarines of the United States Category:Cold War submarines of the United States