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Photo: The Virginia-class attack submarine USS Missouri (SSN 780).

U.S. Navy Fact Sheet

Attack Submarines - SSN


Attack submarines are designed to seek and destroy enemy submarines and surface ships; project power ashore with Tomahawk cruise missiles and Special Operation Forces (SOF); carry out Intelligence, Surveillance, and Reconnaissance (ISR) missions; support battle group operations; and engage in mine warfare.



With the number of foreign diesel-electric/air-independent propulsion submarines increasing yearly, the United States Submarine Force relies on its technological superiority and the speed, endurance, mobility, stealth and payload afforded by nuclear power to retain its preeminence in the undersea battlespace.

The Navy has three classes of SSNs in service. Los Angeles (SSN 688)-class submarines are the backbone of the submarine force with 40 now in commission. Thirty Los Angeles-class SSNs are equipped with 12 Vertical Launch System tubes for firing Tomahawk cruise missiles.

The Navy also has three Seawolf-class submarines. Commissioned on July 19, 1997, USS Seawolf (SSN 21) is exceptionally quiet, fast, well-armed, and equipped with advanced sensors. Though lacking Vertical Launch Systems, the Seawolf class has eight torpedo tubes and can hold up to 50 weapons in its torpedo room. The third ship of the class, USS Jimmy Carter (SSN 23), has a 100-foot hull extension called the multi-mission platform. This hull section provides for additional payloads to accommodate advanced technology used to carry out classified research and development and for enhanced warfighting capabilities.

The Navy continues to build the next-generation attack submarine, the Virginia (SSN 774) class. Twelve VIRGINIA's have been commissioned to date and they will replace Los Angeles Class submarines as they retire. The Virginia class has several innovations that significantly enhance its warfighting capabilities with an emphasis on littoral operations. Virginia class SSNs have a fly-by-wire ship control system that provides improved shallow-water ship handling. The class has special features to support SOF, including a reconfigurable torpedo room which can accommodate a large number of SOF and all their equipment for prolonged deployments and future off-board payloads. The class also has a large lock-in/lock-out chamber for divers. In Virginia-class SSNs, traditional periscopes have been supplanted by two photonics masts that host visible and infrared digital cameras atop telescoping arms. With the removal of the barrel periscopes, the ship's control room has been moved down one deck and away from the hull's curvature, affording it more room and an improved layout that provides the commanding officer with enhanced situational awareness. Additionally, through the extensive use of modular construction, open architecture, and commercial off-the-shelf components, the Virginia class is designed to remain state-of-the-practice for its entire operational life through the rapid introduction of new systems and payloads.

As part of the Virginia-class' third, or Block III, contract, the Navy redesigned approximately 20 percent of the ship to reduce their acquisition costs. Most of the changes are found in the bow where the traditional, air-backed sonar sphere has been replaced with a water-backed Large Aperture Bow (LAB) array which reduces acquisition and life-cycle costs while providing enhanced passive detection capabilities. The new bow also replaces the 12 individual Vertical Launch System (VLS) tubes with two large diameter 87-inch Virginia Payload Tubes (VPTs), each capable of launching six Tomahawk cruise missiles. The VPTs simplify construction, reduce acquisition costs, and provide for more payload flexibility than the smaller VLS tubes due to their added volume. The design changes were successfully proven out during NORTH DAKOTA's Builder Sea Trials in August 2014. Block III hulls include the eight ships procured from Fiscal Years 2008 through and 2013 (SSN hulls 784 - 791.)

Block IV submarines, which are comprised of the 10 submarines scheduled to be authorized in Fiscal Years 2014 - 2018 (SSN hulls 792 - 801), incorporate design changes focused on Reduced Total Ownership Cost (RTOC). By making these smaller-scale design changes to increase the component-level lifecycle of the submarine, the Navy will increase the periodicity between depot maintenance availabilities and increase the number of deployments. Blocks I-III Virginias will undergo four depot maintenance availabilities and conduct 14 deployments. Block IV RTOC efforts reduced the planned availabilities by one to three and increased deployments by one to 15. The Navy refers to this as 3:15.

The next major change will be incorporation of the VIRGINIA Payload Module (VPM) in Block V submarines. VPM, currently in the early concept development phase, will insert four additional payload tubes - each capable of carrying seven Tomahawk cruise missiles - into the Virginia class design. The VPM tubes will be very similar to the VPTs utilized on Block III and forward ships. By using these tubes in the VPM, the Navy leverages mission proven components for the new module, thereby minimizing design and cost risk.

Point Of Contact
Office of Corporate Communication (00D) Naval Sea Systems Command Washington, D.C. 20362
General Characteristics, Virginia Class
Builder: General Dynamics Electric Boat Division and Huntington Ingalls Industries Inc. - Newport News Shipbuilding
Date Deployed: USS Virginia commissioned October 3, 2004
Propulsion: One nuclear reactor, one shaft
Length: 377 feet (114.8 meters)
Beam: 34 feet (10.36 meters)
Displacement: Approximately 7,800 tons (7,925 metric tons) submerged
Speed: 25+ knots (28+ miles per hour, 46.3+ kph)
Crew: 132: 15 officers; 117 enlisted
Armament: Tomahawk missiles, twelve VLS tubes (SSNs 774-783) or two VPTs (SSNs 784 and beyond), MK48 ADCAP torpedoes, four torpedo tubes.
USS Virginia (SSN 774), Groton, CT
USS Texas (SSN 775), Pearl Harbor, HI
USS Hawaii (SSN 776), Pearl Harbor, HI
USS North Carolina (SSN 777), Pearl Harbor, HI
USS New Hampshire (SSN 778), Groton, CT
USS New Mexico (SSN 779), Groton, CT
USS Missouri (SSN 780), Groton, CT
USS California (SSN 781), Groton, CT
USS Mississippi (SSN 782), Pearl Harbor, HI
USS Minnesota (SSN 783), Groton, CT
USS North Dakota (SSN 784), Groton, CT
USS John Warner (SSN 785), Norfolk, VA
Illinois (SSN 786) - Keel laid June 2, 2014
Washington (SSN 787) - Keel laid Nov 11, 2014
Colorado (SSN 788) - Keel laid March 7, 2015
Indiana (SSN 789) - Keel laid May 16, 2015
South Dakota (SSN 790) - Authorized for construction
Delaware (SSN 791) - Authorized for construction
Vermont (SSN 792) - Authorized for construction
Oregon (SSN 793) - Aurthorized for construction
Montana (SSN 794) - Authorized for Construction
Hyman G. Rickover (SSN 795) - Authorized for construction
New Jersey (SSN 796) - Authorized for construction
Iowa (SSN 797) - Under contract
SSN 798 (SSN 798) - Under contract
Idaho (SSN 799) - Under contract
SSN 800 (SSN 800) - Under contract
SSN 801 (SSN 801) - Under contract
General Characteristics, Seawolf Class
Builder: General Dynamics Electric Boat Division.
Date Deployed: USS Seawolf commissioned July 19, 1997
Propulsion: One nuclear reactor, one shaft
Length: SSNs 21 and 22: 353 feet (107.6 meters) SSN 23: 453 feet (138.07 meters)
Beam: 40 feet (12.2 meters)
Displacement: SSNs 21 and 22: 9,138 tons (9,284 metric tons) submerged; SSN 23 12,158 tons (12,353 metric tons) submerged
Speed: 25+ knots (28+ miles per hour, 46.3+ kph)
Crew: 140: 14 Officers; 126 Enlisted
Armament: Tomahawk missiles, MK48 torpedoes, eight torpedo tubes.
USS Seawolf (SSN 21), Bremerton, WA
USS Connecticut (SSN 22), Bremerton, WA
USS Jimmy Carter (SSN 23), Bangor, WA
General Characteristics, Los Angeles Class
Builder: Newport News Shipbuilding Co.; General Dynamics Electric Boat Division
Date Deployed: Nov 13, 1976 (USS Los Angeles)
Propulsion: One nuclear reactor, one shaft
Length: 360 feet (109.73 meters)
Beam: 33 feet (10.06 meters)
Displacement: Approximately 6,900 tons (7011 metric tons) submerged
Speed: 25+ knots (28+ miles per hour, 46.3 +kph)
Crew: 16 Officers; 127 Enlisted
Armament: Tomahawk missiles, VLS tubes (SSN 719 and later), MK48 torpedoes, four torpedo tubes
USS Bremerton (SSN 698), Pearl Harbor, HI
USS Jacksonville (SSN 699), Pearl Harbor, HI
USS Dallas (SSN 700), Groton, CT
USS La Jolla (SSN 701), Pearl Harbor, HI
USS City of Corpus Christi (SSN 705), Pearl Harbor, HI
USS San Francisco (SSN 711), San Diego, CA
USS Houston (SSN 713), Pearl Harbor, HI
USS Buffalo (SSN 715), Pearl Harbor, HI
USS Olympia (SSN 717), Pearl Harbor, HI
USS Providence (SSN 719), Groton, CT
USS Pittsburgh (SSN 720), Groton, CT
USS Chicago (SSN 721), Guam
USS Key West (SSN 722), Guam
USS Oklahoma City (SSN 723), Guam
USS Louisville (SSN 724), Pearl Harbor, HI
USS Helena> (SSN 725), Norfolk, Va.
USS Newport News (SSN 750), Norfolk, VA
USS San Juan (SSN 751), Groton, CT
USS Pasadena (SSN 752), San Diego, CA
USS Albany (SSN 753), Norfolk, VA
USS Topeka (SSN 754), Guam
USS Scranton (SSN 756), Norfolk, VA
USS Alexandria (SSN 757), Portsmouth, NH
USS Asheville (SSN 758), San Diego, CA
USS Jefferson City (SSN 759), Pearl Harbor, HI
USS Annapolis (SSN 760), Groton, CT
USS Springfield (SSN 761), Groton, CT
USS Columbus (SSN 762), Pearl Harbor, HI
USS Santa Fe (SSN 763), Pearl Harbor, HI
USS Boise (SSN 764), Norfolk, VA
USS Montpelier (SSN 765), Norfolk, VA
USS Charlotte (SSN 766), Pearl Harbor, HI
USS Hampton (SSN 767), San Diego, CA
USS Hartford (SSN 768), Groton, CT
USS Toledo (SSN 769), Groton, CT
USS Tucson (SSN 770), Pearl Harbor, HI
USS Columbia (SSN 771), Pearl Harbor, HI
USS Greeneville (SSN 772), Pearl Harbor, HI
USS Cheyenne (SSN 773), Pearl Harbor, HI
Last Update: 9 November 2015