Ohio-class

Ohio-class submarines are the only operational ballistic missile submarines (SSBN) in the U.S. Navy. Four, including the lead ship, USS Ohio (SSGN-726), have been converted to SSGN's, or submarines that can launch a large number of cruise missiles and also be the mother ship for naval special operations forces, typically United States Navy SEALs.

They are named for states of the United States, which were the traditional names for battleships when the battleship was the most important ship type in the Navy.

USS Alaska (SSBN-732) being guided into a weapons loading wharf

SSBN

Ballistic missile variants carry the UGM-133 Trident D5, a submarine launched ballistic missile (SLBM). These missiles are as or more accurate than land-based intercontinental ballistic missiles (ICBMs). While SLBMs traditionally had been seen as survivable second-strike deterrence weapons, the range and accuracy of the missiles gives them first-strike capability. Still, they are seen as more stabilizing than ICBMs, since they are essentially invulnerable. ICBMs, in fixed locations, challenge their commanders to "use them or lose them."

There has been experimentation with a non-nuclear version of the Trident, launched at minimum range at critical targets such as weapons of mass destruction and command centers. The speed of an incoming Trident warhead is such that its kinetic energy, filled with concrete or metal rods, is greater than any possible explosive. Concerns over such weapons, however, come from countries that could detect a launch, principally Russia, but not be able to tell if the payload is nuclear or not.

SSGN

The 1994 Nuclear Posture Review, a Congressionally mandated report, determined, with changing strategic requirements and arms control treaties, that 14 SSBNs, not the operational 18, were adequate to meet national nuclear war needs. Since the first four Ohio class submarines were due for major refuelings and upgrading, the opportunity was taken, given that they would be in shipyards, to convert them to SSGNs.

SSGNs support conventional warfare. Up to 22 of their missile tubes can be adapted to hold either supplies for submarine-based special operations forces, or seven-shot Multiple-All-Up-Round Canisters (MACs) that can launch BGM-109 Tomahawk cruise missiles. This means they can launch up to 154 missiles, more than any surface ship.

Two of the tubes were converted to permanent air locks for SEAL operations. They can also mate with Dry Deck Shelters (DDS) giving even more capacity.

The designated submarines, USS Ohio (SSGN-726), USS Michigan (SSGN-727), USS Florida (SSGN-728) and USS Georgia (SSGN-729) began conversion in 2002 and all were operational by 2008. The first two deployed in 2006. USS Ohio launched Tomahawks at Libya in Operation ODYSSEY DAWN.

General characteristics

• Builder: General Dynamics Electric Boat Division.
• Date Deployed: Nov. 11, 1981 (USS Ohio)
• Propulsion: One nuclear reactor, one shaft.
• Length: 560 feet (170.69 meters).
• Beam: 42 feet (12.8 meters).
• Displacement: 16,764 tons (17,033.03 metric tons) surfaced; 18,750 tons (19,000.1 metric tons) submerged.
• Speed: 20+ knots (23+ miles per hour, 36.8+ kph).
• Crew: 15 Officers, 140 Enlisted.
• Armament: 24 tubes for UGM-133 Trident D5 submarine-launched ballistic missiles, Mark 48 torpedoes, four torpedo tubes.