OHIO modified class (SSGN)

As a result of the START II treaty, signed in June 1992, the number of SSBNs was limited to 14 for each signer until 2002. Then, the US navy decided to remove the 4 surplus of the Ohio class SSBN and transform them into cruise missile armed submarines or SSGN. The four oldest boats were chosen for the conversion, and these were the USS Florida, USS Georgia, USS Michigan and USS Ohio submarines. In 2002, General Dynamics Electric Boat was entrusted with the conversion work, which consisted in the installation of a Multiple All Up Round Canister, (MAC), in 22 of the 24 missile launchers of each submarine. This arrangement allows taking seven Tomahawk TLAM cruise missiles in each vertical launch system, totaling 154 missiles ready for use. In addition, in the two remaining missile launchers, the Advanced Seal Delivery System (ASDS) was installed, which allows the deployment of Navy SEAL units. They can carry up to 66 special operations troops and deploy them secretly anywhere in the Globe. The total cost of this conversion has been about $ 3.2 billion and in 2008 they were active again.

OHIO modified class gallery and more info


Información adicional

Ficha Completa
Country of origin

United States


General Dynamics Electric Boat


Cruise missile nuclear submarine

Entered service

2002 to 2008



Displacement, (full load)

Surfaced: 16,600 tonnes – Submerged: 18,750 tonnes

Dimensions (length x beam x draught)

170.70 x 12.80 x 11.10 meters

Power plant

1 x G.E. S8G PWR nuclear reactor, 2 geared steam turbines

Power, (total)

60,000 shp

Shafts - Screws

1 shaft – 1 screw


Surfaced: 18 knots (33 km/h) – Submerged: 24 knots (44 km/h)

Diving depth, (maximum)

500 meters


4 x 533mm torpedo tubes (with Mk.48 torpedoes)

Cruise missile launcher

22 x MAC launchers for Tomahawk TLAM missiles with 154 missiles


4 boats: Florida – Georgia – Michigan – Ohio