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fighting ships of the world

UNITED STATES NAVY (UNITED STATES OF AMERICA)

SUBMARINES

LOS ANGELES nuclear powered submarines (1976 - 1996)

Los Angeles 1980

San Juan 2000

San Juan 2010

Project history: These submarines restore the speed advantage of the Skipjacks while improving on the sonar and weapons capability of the Sturgeons. The great increase in size (displacement submerged rising from 4650t to 6900t is due largely to a doubling in reactor power. Even so, some sacrifice had to be made in pressure hull strength, so that these craft cannot dive as deeply as their predecessors. Plans originally called for introducing a new hull steel about 1973, which would have restored die depth in later units, but this programme failed to materialise. Reportedly the Los Angeles class gained about 5kts on its predecessor. This class was designed for an all-digital combat system, but it was not ready in time, so SSN688-699 had the earlier Mk 113. The Mk 117 was introduced in SSN 700 and eventually installed not only in the earlier ships of this class but also in the Sturgeons.

    Design work began in 1968 on a new 'mid-1970s' attack submarine, to incorporate both new sensor and propulsion technology and a new stand-off weapon (which would have replaced SUBROC and would have had both anti-ship and antisubmarine roles). In view of the limited internal weapon space available in the torpedo rooms of conventionally designed nuclear submarines, twenty vertical launch tubes would have been provided abaft the fin of the new submarine. Other improvements, such as greatly increased power and improved silencing, added size, so that by December 1972 the new submarine was being described as: 143.8m x 12.2m (as against 102.1m x 10.1m) for a Los Angeles), displacing 13700t submerged (as against 6630t estimated at that time). It would have cost about 80% as much as a Trident missile submarine, then estimated at $500m in FV73 dollars. Admiral Zumwalt cancelled it and its new missile in 1973, and a submarine-launched version of Harpoon was substituted.

    The associated sonar is the new digital BQQ-5, originally comprising a bow sphere and a conformal array similar to that in the Sturgeon class, but using digital beam control (beam preforming) instead of analog beam-forming. Later a towed array, in an external tube, was added.

    Weapon capacity is slightly larger than that of the Sturgeon class, thanks largely to a slightly greater hull diameter (reportedly 26 rather than 23 weapons). In addition, because the Los Angeles was designed from the first to fire the Mk 48 torpedo, its torpedo racks are long enough to accommodate both weapon and wire reel. Earlier submarines were designed for either long free-running torpedoes or for short wire-guided ones (Mk 37), and so had to devote a rack to wire canisters when the long wire-guided weapon appeared.

Units from SSN 719 on have twelve vertical launch tubes for Tomahawk missiles, located between the forward end of the pressure hull and the bow sonar sphere. They carry a total of twenty such missiles (earlier units carry eight, displacing eight torpedoes); SSN 701 was the first of the class to be equipped to fire Tomahawk from her torpedo tubes, but SSN 712 was the first with operational Tomahawk capability (30 November 1983).

    SSN 751 introduced the new BSY-1 integrated submarine combat system and also had retractable bow planes (rather than sail planes) for under-ice operation. These submarines are described as the '688I' class. SSN 768 introduced improved silencing, additional tail fins (like Seawolf) and modified propulsion.

Modernizations: 7.1987, Augusta: + BQG-5D WAA passive sonar system

1980s, Los Angeles, Baton Rouge, Philadelphia, Memphis, Omaha, Cincinnati, Groton, Birmingham, New York City, Indianapolis, Bremerton: - Mk 113 CCS; + Mk 117 CCS

late 1980s, Augusta, Louisville: + BQQ-10 ARCI sonar suite

1989, Memphis: was used as experimental submarine to test composite hull structures, UUVs, advanced sonars, hull friction reduction.

mid-1990s, Memphis: received a GRP turtleback abaft the sail for UUVs and a towing winch and drum for tested towed sonar arrays, 4.27m-high and 1.37m-wide vertical surfaces at the ends of the stern stabilizers to accommodate sonar transducer arrays, and many others

early 1996, Chicago: + Predator Tier II UAV

12.1996, Asheville: + Sea Ferret UAV, AMDS mine detection system

1999, Annapolis: - BRD-7, WLR-8(v)2, WLR-10, WLR-9/12, WLR-1H ECM units; + BLQ-21 ECM suite, BVS-1 optronic system

2000-early 2000s, Los Angeles, Philadelphia, Dallas, La Jolla, Buffalo: + ability to use 1-2 DDS (Dry Deck Shelter) with 1 SDV (swimming delivery vehicle) or 20 SEALs with 4 CRRC (Combat Rubber Raiding Craft).

2000, Charlotte; 2002, Greenville; late 2000s-early 2010s, Columbus, Hartford, Cheyenne: + ability to carry 1 ASDS (70t Advanced SEAL Delivery System) mini-submarine.

2005-2011, Boise, Montpelier, Hampton: - BSY-1 CCS; + BYG-1 CCS

2010s, Cheyenne: + LCCA (Low Cost Conformal Array) sonar

Naval service: San Francisco was badly damaged by grounding submerged off Guam 8.1.2005 and was under repair from November 2006 to November 2008, using constructions from cannibalized Honolulu. Newport News was damaged during collision with Japanese tanker 8.1.2007. Hartford was badly damaged as result of collision with LPD New Orleans 20.3.2009 and was repaired till November 2010. Montpelier was badly damaged in collision with cruiser San Jacinto 13.10.2012 and returned to service in April 2014. Jacksonville was damaged by collision with unidentified object 10.1.2013.

Los Angeles 1979

Toledo 2006

Boise 2008

Dallas with DDS, 2006

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