USS John C. Calhoun (SSBN-630) entering Holy Loch, Scotland on completion of the thousandth Polaris nuclear deterrent patrol, 18 May 1972.
Class overview
Builders	General Dynamics Electric Boat[1] Mare Island Naval Shipyard[1] Portsmouth Naval Shipyard[1] Newport News Shipbuilding and Drydock Company[1]
Operators	United States Navy
Preceded by	Lafayette-class submarine
Succeeded by	Benjamin Franklin-class submarine
Built	1962–1964
In commission	1964–1995
Completed	10
Retired	10
Preserved	1 (As Training Vessel – SSBN-635)
General characteristics
Type	Nuclear-powered Ballistic Missile Submarine
Displacement	Surfaced: 7,325 long tons (7,443 t) Submerged: 8,251 long tons (8,383 t)[2]
Length	425 ft (130 m)
Beam	33 ft (10 m)
Draft	28 ft 6 in (8.69 m)
Propulsion	1 × S5W PWR[1] 2 geared steam turbines (15,000 shp (11,000 kW)), 1 shaft[2]
Speed	16 knots (30 km/h) surfaced 21 knots (39 km/h) submerged[2]
Test depth	1,300 feet (400 m)[2]
Complement	Two crews of 14 officers and 126 enlisted[2]
Armament	16 Polaris A3 or Poseidon C3 or Trident I C4 missiles, 4 × 21 inch (533 mm) torpedo tubes, 12 torpedoes[2]

The James Madison class of submarine was an evolutionary development from the Lafayette class of fleet ballistic missile submarine. They were identical to the Lafayettes except for being initially designed to carry the Polaris A-3 missile instead of the earlier A-2. This class, together with the George Washington, Ethan Allen, Lafayette, and Benjamin Franklin classes, composed the "41 for Freedom" that was the Navy's primary contribution to the nuclear deterrent force through the late 1980s. This class and the Benjamin Franklin class are combined with the Lafayettes in some references.

Design

In the early 1970s all were modified for the Poseidon C-3 missile. During the late 1970s and early 1980s, six boats were further modified to carry the Trident I C-4 missile, along with six Benjamin Franklin-class boats. These were James Madison, Daniel Boone, John C. Calhoun, Von Steuben, Casimir Pulaski, and Stonewall Jackson.^[3]

Fate

The James Madisons were decommissioned between 1986 and 1995 due to a combination of SALT II treaty limitations as the Ohio class SSBNs entered service, age, and the collapse of the Soviet Union. One (Sam Rayburn) remains out of commission but converted to a Moored Training Ship (MTS-635) with the missile compartment removed. She is stationed at Norfolk Naval Shipyard in Portsmouth, VA for inactivation.^[3]

Boats in class

Submarines of the James Madison class:^[3][4] (Submarines marked with * indicate Trident I C-4 ballistic missile conversions.)