fighting ships of the world



SEAWOLF nuclear powered submarines (1997 - 1998)

Seawolf 2000

No Name Yard No Builder Laid down Launched Comm Fate
SSN21 Seawolf 253 General Dynamics, Electric Boat Div., Groton 25/10/1989 start 24/6/1995 19/7/1997 in service (2019)
SSN22 Connecticut 255 General Dynamics, Electric Boat Div., Groton 14/9/1992 start 1/9/1997 11/12/1998 in service (2019)


Displacement standard, t


Displacement normal, t

7467 / 9138

Length, m


Breadth, m


Draught, m


No of shafts

1 pumpjet


2 geared steam turbines, 1 Westinghouse S6W nuclear reactor

Power, h. p.


Max speed, kts

 / 39

Fuel, t


Endurance, nm (kts)

practically unlimited


8 - 673 TT (amidships, 50 torpedoes, inc. 12 Tomahawk UGM-109 CruM instead of part of torpedoes or 100 mines)


BPS-16(v)3 radar, BQQ-5D sonar suite, BQS-24 sonar, TB-23, TB-16D towed arrays, WLQ-4(v)1 ECM suite, BLD-1 D/F, BLQ-10 decoy launchers, BSY-2(v) CCS



Diving depth operational, m



Ship project history: This was the first new attack submarine to be designed after the Los Angeles class. There had been several proposals during the 1970s, but none was considered sufficiently superior to the gradually evolving Los Angeles. The new Seawolf combined a new quieter reactor with a new quiet propulsion (a pumpjet), a better hull shape (lower length / beam ratio), and much more firepower, in the form of twice as many tubes and twice as many internally-stowed weapons. Seawolf is somewhat faster than Los Angeles, but it has a much higher quiet (tactical) speed, reportedly about twice that of the earlier class. The new submarine is equipped with a new distributed combat system, BSY-2, which incorporates a new bow sonar (a pair of spheres), the flank array (WWAA) installed on late Los Angeles class boats, and a pair of towed arrays (a thick TB-16D and a thin TB-29). There is also an active ice- and mine-avoidance sonar, SADS/MIDAS. Seawolf was designed for relatively inexpensive maintenance, so that although its unit cost is very high, its total life-cycle cost is intended to match that of earlier submarines. Overhaul (including reactor refuelling) should not be necessary for fifteen years. The first unit was authorised in FY89, for launching in January 1994 and completion in May 1995. These dates probably were not be met, because difficulties were experienced in welding its new HY-100 steel. The torpedo tubes were originally referred to as being 762mm in diameter, but liners and other fittings restrict the diameter of weapons and remotely controlled reconnaissance vehicles launched from them to 673mm; the launch system is virtually soundless, but the outer doors can not be opened when the submarine is traveling at maximum speed.

    Seawolf was also called SSN-21, the nuclear submarine of the twenty-first century, and this new number superseded the original hull number, SSN774, on numerous official documents. SSN22 was authorised under FY91 and SSN23 under FY92, although final construction authority was not granted by Congress until FY96 and funding was not provided until FY97. As of 1999, the total cost of the three-submarine program was estimated at $16 billion.

    Opposition to mass production of so expensive a submarine led the navy to work on a less expensive follow-on Virginia class, initially called 'Centurion'.

Although commissioned in July 1997, SSN21 did not commence her first operational patrol until June 2001.

Modernizations: planned: - BQQ-5D sonar suite, TB-16D towed array, BSY-2(v) CCS; + BQQ-10 sonar suite, TB-34 towed array, BLQ-10 ECM, BYG-1 CCS

Naval service: No significant events.

Connecticut 1998


Seawolf 2001

Ivan Gogin, 2016-19