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Virginia class submarine

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USS Virginia (SSN-774)
USS Virginia
Class overview
Name: Virginia
Builders: General Dynamics Electric Boat, Northrop Grumman Newport News
Operators: Naval flag of United States United States Navy
Preceded by: Seawolf class attack submarine
In commission: 2004-10-23
Building: 3
Planned: 30
Completed: 5
Active: 5
General characteristics
Class and type: Attack submarine
Displacement: 7,900 tonnes (7,800 long tons)
Length: 377 feet (115 m)
Beam: 34 feet (10 m)
Propulsion: S9G reactor
Speed: >25 knots (46 km/h)
Range: unlimited except by food supplies
Test depth: > 800 ft (244 m)
Complement: 134
Armament:

12xVLS (BGM-109 Tomahawk cruise missile) &

4x533mm torpedo tubes (Mk-48 torpedo)
Notes: Ships in class include: Virginia, Texas, Hawaii, North Carolina, New Hampshire, New Mexico, Missouri, California, Mississippi, Minnesota, North Dakota

The Virginia class (or SSN-774 class) of attack submarines are U.S. subs designed for a broad spectrum of open-ocean and littoral missions. They were designed as a less expensive alternative to the Cold War era designed Seawolf-class attack submarines, and they are slated to replace the aging Los Angeles class subs, seventeen of which (from a total of 62) have already been decommissioned.

Contents

[edit] Innovations

The Virginias incorporate several innovations. Instead of periscopes, the subs have a pair of extendable photonics masts[1] outside the pressure hull. Each contains several high-resolution cameras with light-intensification and infrared sensors, an infrared laser rangefinder, and an integrated Electronic Support Measures (ESM) array. Signals from the masts' sensors are transmitted through fiber optic data lines through signal processors to the control center. The subs also make use of pump-jet propulsors for quieter operations.

[edit] Construction and controversy

The Virginias were intended, in part, as a cheaper ($1.8 vs $2 billion) alternative to the Seawolf class, whose production run was stopped after just three boats. To reduce costs, the Virginia-class uses many "commercial-off-the-shelf" (or COTS) components, especially in their computers and data networks. In practice they actually cost about $2.3 billion (in fiscal year 2005 dollars) each, due in part to the lack of an economy of scale.

In hearings before both House of Representatives and Senate committees, the Congressional Research Service and expert witnesses testified that the current procurement plans of the Virginia class—one per year at present, accelerating to two per year beginning in 2012—resulted in high unit costs and (according to some of the witnesses and some of the committee chairmen)[2] an insufficient number of attack submarines. In a March 10, 2005 statement[3] to the House Armed Services Committee, Ronald O'Rourke of the CRS testified that, assuming the production rate remains as planned, "production economies of scale for submarines would continue to remain limited or poor."

The Virginia-class is built through an industrial arrangement designed to keep both GD Electric Boat and Northrop Grumman Newport News (the only two U.S. shipyards capable of building nuclear-powered vessels) in the submarine-building business[4]. Under the present arrangement, the Newport News facility builds the stern, habitability & machinery spaces, torpedo room, sail and bow, while Electric Boat builds the engine room and control room. The facilities alternate work on the reactor plant as well as the final assembly, test, outfit and delivery.

O’Rourke wrote[5] in 2004 that, "Compared to a one-yard strategy, approaches involving two yards may be more expensive but offer potential offsetting benefits." Among the claims of "offsetting benefits" that O'Rourke attributes to supporters of a two-facility construction arrangement is that it "would permit the United States to continue building submarines at one yard even if the other yard is rendered incapable of building submarines permanently or for a sustained period of time by a catastrophic event of some kind", including an enemy attack.

In order to get the submarine's price down to $2 billion per submarine in FY-05 dollars, the Navy instituted a cost-reduction program to shave off approximately $400 million in costs off each submarine's price tag. The project was dubbed "2 for 4 in 12," referring to the Navy's desire to buy two boats for $4 billion in FY-12. Under pressure from Congress, the Navy opted to start buying two boats a year earlier, in FY-11, meaning that officials would not be able to get the $2 billion price tag before the service started buying two subs per year. However, program manager Dave Johnson said at a conference on March 19, 2008, that the program was only $30 million away from achieving the $2 billion price goal, and would reach that target on schedule.[6]

In December 2008, the US Navy signed a $14 billion contract with General Dynamics and Northrop Grumman, to supply eight submarines. The contractors will deliver one submarine in each of fiscal 2009 and 2010, and two submarines on each of fiscal 2011, 2012 and 2013.[7] This contract will bring the Navy's Virginia-class fleet to 18 submarines.

On 21 June 2008, the Navy christened the New Hampshire (SSN-778), the first of the Block II submarine. This boat was delivered eight months ahead of schedule and $54 million underbudget.[8] The Block II boats are built in four sections, compared to the ten sections of the Block I boats. This enables a cost saving of about $300 million per boat, reducing the overall cost to $2 billion per boat and the construction of two new boats per year. Beginning in 2010, new submarines of this class will include a software system that can monitor and reduce their electromagnetic signatures when needed.[9]

[edit] Technical information

The launching of the USS Texas (SSN-775)
Control station in torpedo room of USS Virginia (SSN-774)
USS Virginia (SSN-774) under construction
USS New Hampshire (SSN-778) the first of the Block II vessels

[edit] General characteristics

  • Builders: GD Electric Boat and Northrop Grumman Newport News
  • Length: 377 ft (114.91 m)
  • Beam: 34 ft (10.36 m)
  • Displacement: 7,800 tons
  • Payload: 40 weapons, special operations forces, unmanned undersea vehicles, Advanced SEAL Delivery System (ASDS)
  • Propulsion: The S9G nuclear reactor
  • Maximum diving depth: greater than 800 ft (244 m)
  • Speed: 25+ knots[10]
  • Planned cost: about US$1.65 billion each (based on FY95 dollars, 30-ship class and two ship/year build-rate, which has not yet been authorized)
  • Actual cost: about $2.5 billion each (as of SSN-776, 2007)[11]
  • Crew: 120 enlisted and 14 officers
  • Armament: 12 VLS & four torpedo tubes, capable of launching Mark 48 torpedoes, Harpoon missiles, UGM-109 Tactical Tomahawks, and the new advanced mobile mine when it comes available.

[edit] Boats

[edit] Block I

[edit] Block II

[edit] Block III

[edit] See also

[edit] References

  1. ^ "Photonics Mast (PMP) System" (PDF). Kollmorgen Electro-Optical. July 2004. http://www.eo.kollmorgen.com/uploads/textWidget/wysiwyg/documents/AD-16_PMP_datasht.pdf. Retrieved on 2008-03-01. 
  2. ^ "Statement of The Honorable Duncan Hunter, Chairman, Subcommittee on Military Procurement, Submarine Force Structure and Modernization". FAS Military Analysis Network. Federation of American Scientists. June 27, 2000. http://www.fas.org/man/congress/2000/00-06-27hunter.htm. Retrieved on 2008-03-01. 
  3. ^ "(dead link)" (PDF). http://www.house.gov/hasc/testimony/109thcongress/Projection%20Forces/3-10-05O'RourkeCRS.pdf. Retrieved on 2008-03-01. [dead link]
  4. ^ "SSN-774 Virginia-class NSSN New Attack Submarine" (HTML). Federation of American Scientists. January 19, 2009. http://www.fas.org/man/dod-101/sys/ship/nssn.htm. 
  5. ^ Ronald O’Rourke (June 2, 2004). "Navy Attack Submarine Force-Level Goal and Procurement Rate: Background and Issues for Congress" (PDF). Federation of American Scientists. http://www.fas.org/man/crs/RL32418.pdf. Retrieved on 2008-03-01. 
  6. ^ http://insidedefense.com/secure/defense_docnum.asp?f=defense_2002.ask&docnum=NAVY-21-12-4
  7. ^ General Dynamics And Northrop Awarded Submarine Deal, New YorkTimes, December 22, 2008
  8. ^ U.S. Navy Office of the Information - U.S. Navy Public Affairs Resources page
  9. ^ http://www.globalsecurity.org/military/systems/ship/ssn-774-spiral-1.htm
  10. ^ "The US Navy -- Fact File". http://www.navy.mil/navydata/fact_display.asp?cid=4100&tid=100&ct=4. Retrieved on 2007-07-05. 
  11. ^ "The Day, New London, CT". http://www.theday.com/re.aspx?re=4aa3b13d-81ae-4400-bc58-e83a6b4ae230. Retrieved on 2008-02-23. 
  12. ^ "Navy Takes Delivery of New Submarine". Military.com. February 22, 2008. http://www.military.com/features/0,15240,162635,00.html?ESRC=navy.nl. Retrieved on 2008-03-01. 
  13. ^ "Hartford Courant". http://www.courant.com/news/local/statewire/hc-21132404.apds.m0766.bc-ct--subcjun21,0,4795469.story. Retrieved on 2007-06-21. 
  14. ^ a b c "Navy Secretary Names Three New Virginia Class Attack Submarines". DefenseLink.mil. January 30, 2008. http://www.defenselink.mil/releases/release.aspx?releaseid=11652. Retrieved on 2008-03-01. 
  15. ^ General Dynamics press release, December 28, 2006.
  16. ^ a b "Navy Names Two Virginia Class Submarines". DefenseLink.mil. July 15, 2008. http://www.defenselink.mil/releases/release.aspx?releaseid=12067. Retrieved on 2008-07-15. 
  17. ^ "Navy Names Virginia Class Submarine USS John Warner Story Number: NNS090108-13". http://www.navy.mil/search/display.asp?story_id=41713. Retrieved on 2009-01-09. 
  18. ^ "Virginia Block III: The Revised Bow". http://www.defenseindustrydaily.com/virginia-block-iii-the-revised-bow-04159/. Retrieved on 2008-05-20. 

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