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SSN-688 Los Angeles-class

The LOS ANGELES class SSN specifically included ASW against Soviet submarines trying to sink the US carrier and ASUW against capital ships in the Soviet surface action group [SAG]. The LOS ANGELES class SSN was designed almost exclusively for Carrier Battlegroup escort; they were fast, quiet, and could launch Mk48 and ADCAP torpedoes, Harpoon Anti-Ship Missiles (no longer carried), and both land attack and anti-ship (no longer carried) Tomahawk cruise missiles. The new submarines showed another step improvement in quieting and an increase in operating speed to allow them to support the CVBG. Escort duties included conducting ASW sweeps hundreds of miles ahead of the CVBG and conducting attacks against the SAG.

Submarines of the LOS ANGELES Class are among the most advanced undersea vessels of their type in the world. While anti-submarine warfare is still their primary mission, the inherent characteristics of the submarine's stealth, mobility and endurance are used to meet the challenges of today's changing global geopolitical climate. Submarines are able to get on station quickly, stay for an extended period of time and carry out a variety of missions including the deployment of special forces, minelaying, and precision strike land attack.

These 360 foot, 6,900-ton ship are well equipped to accomplish these tasks. Faster than her predecessors and possessing highly accurate sensors, weapons control systems and central computer complexes, the LOS ANGELES Class is armed with sophisticated MK-48 Advanced Capability anti-submarine/ship torpedoes, Tomahawk land attack cruise missiles, and mines.

These submarines were built in three successive variants:

The USS MEMPHIS (SSN 691) has been modified to serve as a test and evaluation platform for advanced submarine systems and equipment, while retaining her combat capability.

The submarines are outfitted with a wide variety of antennas, transmitters and receivers necessary to support accomplishment of their assigned tasks. Interior communication is possible on a wide range of circuits and sound powered phones which do not require electrical power and are reliable in battle situations. Various alarm and indicating circuits enable the Officer of the Deck and the Engineering Officer of the Watch to continuously monitor critical parameters and equipment located throughout the ship.

The nuclear power plant gives these boats the ability to remain deployed and submerged for extended periods of time. To take advantage of this, the ship is outfitted with auxiliary equipment to provide for the needs of the crew. Atmosphere control equipment replenishes oxygen used by the crew, and removes carbon dioxide and other atmosphere contaminants. The ship is equipped with two distilling plants which convert salt water to fresh water for drinking, washing and the propulsion plant. Sustained operation of the complex equipment and machinery on the ship requires the support of repair parts carried on board. The ship carries enough food to feed a crew of over one hundred for as long as 90 days.

Cutaway of the USS Oklahoma City

Los Angeles class submarines are divided into two watertight compartments. The forward compartment houses all the living spaces, weapons systems, control centers, and sonar/fire control computers. The after compartment houses the nuclear reactor and the ship's propulsion equipment.

1. Engine Room. The engine room houses all the propulsion machinery, as well as the Ship's Service Turbine Generators that supply the ship's electricity, and the evaporator, which distills water for the propulsion plant and other shipboard use.

2. Control Room/Attack Center. Located in the upper level of the forward compartment is the control room--the heart of the ship. The Officer of the Deck stands his watch here, controlling all activities on board. In control, the ship's location is continually determined and plotted, the course and depth are controlled, and all sonar contacts are tracked. The control room also functions as the attack center, where all of the ship's weapon systems are controlled from.. The sail helps to add stability to the submerged vessel. Additionally it houses all of the periscopes and antennae. In the forward top portion of the sail is the bridge. When the ship is on the surface, the Officer of the Deck will shift his watch to the bridge. Here he has clear view of all the surrounding waters, in addition to getting a breath of fresh air and seeing the welcome sun.

4. Mess Decks, Berthing, and Wardroom. The middle level of the forward compartment is dedicated to the crew's living spaces. Here is found the mess decks and galley which, when underway, serve four meals a day, one every six hours (allowing for all watchstanders to get a hot meal). Also here are the berthing spaces. Here is the only personal space that a crewman gets--his bed (known as a "rack". These racks are stacked three tall throughout the berthing spaces and have only a curtain to close them off from the rest of the boat. With this as the only private area on board, it is not uncommon to find pictures of family and friends put up on the wall in a rack along with personal cassette and CD players for entertainment. The wardroom> is the officers own room. Here is a big table around which the officers eat, train, and work

5. Torpedo Room. The lower level of the forward compartment is the Torpedo Room. This room stores the ship's weapons which include Mk48 ADCAP torpedoes, Tomahawk cruise missiles, and mines. The torpedo room houses the handling equipment and access to the ship's four torpedo tubes. Weapons are moved from their stowage positions, loaded into the tubes, and readied for launch all in this room by the ship's Torpedomen. The torpedo room also houses controls for the vertical launch tubes which add 12 more Tomahawk cruise missiles to the ship's load.

6. Sonar Sphere. Housed in the very forward end of the submarine is the sonar sphere. This is an array of over 1,000 hydrophones which makes up part of the advanced BQQ-5E sonar suite. Out in front of the ship, positions the sphere as far as possible from the ship's own noise, thereby giving it the best listening conditions.

SSN 688-class submarines, which will comprise 68% of the attack submarine force in 2015, must be modernized to ensure that they remain effective against increasingly sophisticated undersea adversaries. The use of COTS and open systems architecture (OSA) will enable rapid (annual) updates to both software and hardware, and the use of COTS-based processors means that sonar system computing power can grow at the same rate as commercial technology.

The creation of the Acoustic Rapid COTS Insertion (A-RCI) program was based on a detailed review of the U.S. acoustic advantage compared to foreign nuclear and diesel electric submarines. This program is the centerpiece of the Los Angeles (SSN 688)-class modernization effort. SSN 688 class submarines, which will comprise 68% of the attack submarine force in 2015, must be modernized to ensure that they remain effective when operating against increasingly sophisticated undersea adversaries. The use of COTS and Open Systems Architecture (OSA) will enable rapid (annual) updates to both software and hardware, and the use of COTS-based processors means that sonar system computing power can grow at the same rate as the commercial world.

A-RCI is a four phased transformation of existing sonar systems (AN/BSY-1, AN/BQQ-5, or AN/BQQ-6) to a more capable and flexible COTS/OSA-based system. It also will provide the submarine force with a common sonar system. The process is designed to minimize the impact of fire-control and sonar system upgrades on a ship's operational schedule, and will be accomplished without the need for major shipyard availabilities. Phase I, which commenced in November 1997, will enhance towed-array processing. Phase II will provide additional towed- and hull-array software upgrades. Phase III will upgrade the spherical array, and Phase IV will upgrade the high-frequency sonar system on SSN 688I-class submarines. Each phase will install improved processing and control and display workstations. The current installation plan completes all SSNs through Phase III by FY03.

Between 1998 and 2001 the US will retire 11 Los Angeles class submarines that have an average of 13 years left on their 30-year service lives. SSN-688 class submarines could operate for much longer than 30 years; one of the shipbuilders stated that 10 to 20 years of additional service would not be unreasonable. Past Navy actions indicate that extending a submarine's service life may be feasible. After a 5-year study was completed on the SSN-637 class submarine--the predecessor of the SSN-688 class--the design life was extended from 20 years to 30 years, with a possible extension to 33 years on a case-by-case basis. The 18 SSN-688 class submarines that will be refueled at their mid-life could make good candidates for a service life extension because they could operate for nearly 30 years after the refueling. After these submarines serve for 30 years, they could undergo a 2-year overhaul and serve for one more 10-year operating cycle, for a total service life of 42 years. The cost for the additional overhaul of SSN-688 class submarines would be about $406 million per boat.

Eight older Los Angeles-class submarines, without a vertical launch system, could be refueled at a cost of $210 million more than it would cost to inactivate them. These submarines can still be used in strike missions, however, by firing Tomahawk land attack missiles through their torpedo tubes.

The existing DOD guidance calls for a force of 50 attack submarines, although some studies have called for raising the number of subs to as many as 72. Existing plans are sufficient to meet the goal of 50 boats, although higher numbers would require modification to these plans. According to Navy secretary Richard Danzig, as of October 1999 the Joint Chiefs of Staff were studying options for increasing the size and capability of the submarine force. The three options under review include by converting older Ohio-class SSBN submarines to so-called SSGNs at a cost of $420 million; refueling and extending by 12 years the service life of perhaps eight Los Angeles-class (SSN 688) subs at a cost per copy of $200 million; or building new Virginia-class (SSN 774) subs at a rate of at least four over the next five years, at a cost of roughly $2 billion per boat. The FY2000 Defense Authorization bill requires the Navy to study converting four of the oldest Tridents to the new SSGN configuration.

The JCS Submarine Force Structure Study, completed in November 1999, concluded that the optimal force structure would be 68 attack submarines by 2015 and 76 by 2025, with the minimum being at least 55 by 2015 and 62 by 2025. The first would be to refuel some Los Angeles-class submarines previously scheduled to be decommissioned.


Builders Newport News Shipbuilding Co.
General Dynamics Electric Boat Division.
Power Plant One S6G reactor
one shaft at 35,000 shp
Improved Performance Machinery Program Phase I [on 688 Improved]
Length 360 feet (109.73 meters)
Beam 33 feet (10 meters)
Displacement 6,927 tons (6210 metric tons) submerged
SpeedOfficial: 20+ knots (23+ miles per hour, 36.8 +kph)
Actual: 30-32 knots maximum submerged speed
Operating Depth official: "greater than 800 feet"
Actual: 950 feet [300 meters] test depth
Actual: 1475 feet [450 meters] collapse depth
Hull HY-80 Steel
Crew 13 Officers, 116 Enlisted


Armament Harpoon and Tomahawk ASM/LAM missiles from VLS tubes
MK-48 torpedoes from four 533-mm torpedo tubes (Seawolf has 8)
Combat Systems AN/BPS-5 surface search radar
AN/BPS-15 A/16 navigation and fire control radar

TB-16D passive towed sonar arrays
TB-23 passive "thin line" towed array
AN/BQG-5D wide aperture flank array
AN/BQQ-5D/E low frequency spherical sonar array
AN/BQS-15 close range active sonar (for ice detection);
MIDAS Mine and Ice Detection Avoidance System
SADS-TG active detection sonar

Type 2 attack periscope (port)
Type 18 search periscope (starboard)

AN/BSY-1 (primary computer);
UYK-7; UYK-43; UYK-44

WLR-9 Acoustic Intercept Receiver
Unit Cost $900 million [1990 prices]
Unit Operating Cost
Annual Average
~$21,000,000 [source: [FY1996 VAMOSC]


Name Number Builder Homeport Ordered Commissioned Decommissioned
Los Angeles SSN 688 Newport News Pearl Harbor 08 Jan 1971 13 Nov 1976
Baton Rouge SSN-689 Newport News Norfolk 08 Jan 1971 25 Jun 1977 13 Jan 1995
Philadelphia SSN 690 Electric Boat Groton 08 Jan 1971 25 Jun 1977
Memphis SSN 691 Newport News Groton 04 Feb 1971 17 Dec 1977
Omaha SSN-692 Electric Boat Pearl Harbor 31 Jan 1971 11 Mar 1978 05 Oct 1995
Cincinnati SSN-693 Newport News Norfolk 04 Feb 1971 10 Jun 1978 29 Jul 1996
Groton SSN-694 Electric Boat Groton 31 Jan 1971 08 Jul 1978 07 Nov 1997
Birmingham SSN-695 Newport News Pearl Harbor 24 Jan 1972 16 Dec 1978 22 Dec 1997
New York City SSN-696 Electric Boat Pearl Harbor 24 Jan 1972 03 Mar 1979 30 Apr 1997
Indianapolis SSN 697 Electric Boat Pearl Harbor 24 Jan 1972 05 Jan 1980 17 Feb 1998
Bremerton SSN 698 Electric Boat Pearl Harbor 24 Jan 1972 28 Mar 1981 ~2001
Jacksonville SSN 699 Electric Boat Norfolk 24 Jan 1972 16 May 1981 ~2001
Dallas SSN 700 Electric Boat Groton 31 Jan 1973 26 Jun 1981
La Jolla SSN 701 Electric Boat San Diego 10 Dec 1973 30 Sep 1981
Phoenix SSN-702 Electric Boat Norfolk 31 Oct 1973 12 Dec 1981 29 Jul 1998
Boston SSN 703 Electric Boat Groton 10 Dec 1973 30 Jan 1982 18 Jan 1999
Baltimore SSN 704 Electric Boat 31 Oct 1973 24 Jul 1982 10 Jul 1998
City Of Corpus Christi SSN 705 Electric Boat Groton 31 Oct 1973 08 Jan 1983
Albuquerque SSN 706 Electric Boat Groton 31 Oct 1973 21 May 1983
Portsmouth SSN 707 Electric Boat San Diego 10 Dec 1973 01 Oct 1983
Minneapolis-St. Paul SSN 708 Electric Boat Norfolk 31 Oct 1973 10 Mar 1984
Hyman G. Rickover SSN 709 Electric Boat Norfolk 10 Dec 1973 21 Jul 1984
Augusta SSN 710 Electric Boat Groton 31 Oct 1973 19 Jan 1985 ~2008
San Francisco SSN 711 Newport News Pearl Harbor 01 Aug 1975 21 Apr 1984
Atlanta SSN 712 Newport News Norfolk 01 Aug 1975 06 Mar 1982 22 Jan 1999
Houston SSN 713 Newport News San Diego 01 Aug 1975 25 Sep 1982 ~2000
Norfolk SSN 714 Newport News Norfolk 20 Feb 1976 21 May 1983 ~2001
Buffalo SSN 715 Newport News Pearl Harbor 23 Feb 1976 05 Nov 1983
Salt Lake City SSN 716 Newport News San Diego 15 Sep 1977 12 May 1984 ~2005
Olympia SSN 717 Newport News Pearl Harbor 15 Sep 1977 17 Nov 1984 ~2006
Honolulu SSN 718 Newport News Pearl Harbor 15 Sep 1977 06 Jul 1985 ~2007
Providence SSN 719 Electric Boat Groton 16 Apr 1977 27 Jul 1985
Pittsburgh SSN 720 Electric Boat Groton 16 Apr 1977 23 Nov 1985
Chicago SSN 721 Newport News Pearl Harbor 13 Aug 1981 27 Oct 1986
Key West SSN 722 Newport News Pearl Harbor 13 Aug 1981 12 Sep 1987
Oklahoma City SSN 723 Newport News Norfolk 13 Aug 1981 09 Jul 1988
Louisville SSN 724 Electric Boat Pearl Harbor 11 Feb 1981 08 Nov 1986
Helena SSN 725 Electric Boat Pearl Harbor 19 Apr 1982 11 Jul 1987
Newport News SSN 750 Newport News Norfolk 19 Apr 1982 03 Jun 1989
IMPROVED 688 - 688I
San Juan SSN 751 Electric Boat Groton 30 Nov 1982 06 Aug 1988
Pasadena SSN 752 Electric Boat Pearl Harbor 30 Nov 1982 11 Feb 1989
Albany SSN 753 Newport News Norfolk 20 Nov 1983 07 Apr 1990
Topeka SSN 754 Electric Boat Pearl Harbor 28 Nov 1983 21 Oct 1989
Miami SSN 755 Electric Boat Groton 28 Nov 1983 30 Jun 1990
Scranton SSN 756 Newport News Norfolk 26 Nov 1984 26 Jan 1991
Alexandria SSN 757 Electric Boat Groton 26 Nov 1984 29 Jun 1991
Asheville SSN 758 Newport News Pearl Harbor 26 Nov 1984 28 Sep 1991
Jefferson City SSN 759 Newport News San Diego 26 Nov 1984 29 Feb 1992
Annapolis SSN 760 Electric Boat Groton 21 Mar 1986 11 Apr 1992
Springfield SSN 761 Electric Boat Groton 21 Mar 1986 09 Jan 1993
Columbus SSN 762 Electric Boat Pearl Harbor 21 Mar 1986 24 Jul 1993
Santa Fe SSN 763 Electric Boat Pearl Harbor 21 Mar 1986 11 Dec 1993
Boise SSN 764 Newport News Norfolk 06 Feb 1987 07 Nov 1992
Montpelier SSN 765 Newport News Norfolk 06 Feb 1987 13 Mar 1993
Charlotte SSN 766 Newport News Pearl Harbor 06 Feb 1987 16 Sep 1994
Hampton SSN 767 Newport News Norfolk 06 Feb 1987 16 Nov 1993
Hartford SSN 768 Electric Boat Groton 30 Jun 1988 10 Dec 1994
Toledo SSN 769 Newport News Groton 10 Jun 1988 24 Feb 1995
Tucson SSN 770 Newport News Pearl Harbor 10 Jun 1988 18 Aug 1995
Columbia SSN 771 Electric Boat Pearl Harbor 14 Dec 1988 09 Oct 1995
Greenville SSN 772 Newport News Pearl Harbor 14 Dec 1988 16 Feb 1996
Cheyenne SSN 773 Newport News Norfolk 28 Nov 1989 13 Sep 1996

SSN-688 Los Angeles-class Image Gallery

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Maintained by Robert Sherman
Originally created by John Pike
Updated Monday, February 14, 2000 4:50:53 PM