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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.

Innovations

The Virginias incorporate several innovations. Instead of periscopes, the subs have a pair of extendable photonics masts 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.

 will be the first Virginia with the advanced electromagnetic signature reduction system built in, but this will be refitted into the other submarines of the class.


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) an insufficient number of attack submarines. In a March 10, 2005 statement 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 Newsmarker (the only two U.S. shipyards capable of building nuclear-powered vessels) in the submarine-building business. Under the present arrangement, the Newport News facility builds the stern, habitability and 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 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.

In December 2008, the 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. This contract will bring the Navy's Virginia class fleet to 18 submarines.

On 21 June 2008, the Navy christened the , the first Block II submarine. This boat was delivered eight months ahead of schedule and $54 million underbudget. 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.

Technical information

The launching of the
Control station in torpedo room of
under construction
the first of the Block II vessels


General characteristics

  • Builders: GD Electric Boat and Northrop Grumman Newport Newsmarker
  • 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
  • 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)
  • Crew: 120 enlisted and 14 officers
  • Armament: 12 VLS & four torpedo tubes, capable of launching Mark 48 torpedoes, Harpoon missiles, UGM-109 Tactical Tomahawk, and the new advanced mobile mine when it comes available.


Boats

Block I



Block II

  • USS New Hampshire , commissioned and in service.
  • New Mexico has been ordered for delivery in January, 2010.
  • Missouri , named January 30, 2008 and is expected to be delivered in April, 2011.
  • California , named January 30, 2008 and is expected to be delivered in 2013.
  • Mississippi , named January 30, 2008 and is expected to be delivered in 2013.
  • Minnesota , named July 15, 2008 and is expected to be delivered in 2014.


Block III

  • North Dakota , named July 15, 2008 and is expected to be delivered in 2014.
  • John Warner , named January 8, 2009 and is expected to be delivered April 30, 2015.
  • SSN-784 through approximately SSN-791 are planned to make up the Third Block or "Flight" and should begin construction in 2009. Block III subs will feature a revised bow, including some technology from Ohio class SSGNs.



Tango Bravo

Because of the slow rate of Virginia production, the Navy entered into a program with DARPA to overcome Technology Barriers (TB or Tango Bravo) to lower the cost of attack submarines so that more could be built to keep up the size of the fleet.

These include:
  • Propulsion concepts not constrained by a centerline shaft.


  • Externally stowed and launched weapons (especially torpedoes).


  • Conformal alternatives to the existing spherical sonar array.


  • Technologies that eliminate or substantially simplify existing submarine hull, mechanical and electrical systems.


  • Automation to reduce crew workload for standard tasks.


See also



References

External links




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