14 March 2015
U.S. Navy's total requirement is for 30 Virginia-class attack submarines. The Navy placed a bulk-buy contract for the first five ships and, in January 2004, placed a multiyear contract for the following five.
The Virginia-class of attack submarines surpasses the performance of any current projected threat submarine. They were designed as a cheaper alternative to the Cold War era Seawolf-class attack submarines, and are slated to replace aging Los Angeles class subs, seventeen of which have already been decommissioned.
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.
The hull size is length 377ft by beam 34ft and the displacement is 7,300t dived, which is smaller than the more expensive Seawolf attack submarine with displacement 9,137t dived.
The submarine is fitted with modular isolated deck structures, for example the submarine's command centre will be installed as one single unit resting on cushioned mounting points. The submarine's control suite is equipped with computer touch screens.
The submarine is equipped with 12 vertical missile launch tubes and four 533mm torpedo tubes. The vertical launching system has the capacity to launch 16 Tomahawk submarine-launched cruise missiles (SLCM) in a single salvo. There is capacity for up to 26 mk48 ADCAP mod 6 heavyweight torpedoes and sub harpoon anti-ship missiles to be fired from the 21in torpedo tubes. Mk60 CAPTOR mines may also be fitted.
An integral lock-out / lock-in chamber is incorporated into the hull for special operations. The chamber can host a mini-submarine, such as Northrop Grumman's Oceanic and Naval Systems advanced SEAL delivery system (ASDS), to deliver special warfare forces such as navy sea air land (SEAL) teams or Marine reconnaissance units for counter-terrorism or localised conflict operations.
Virginia is fitted with the AN/WLY-1 acoustic countermeasures system being developed by Northrop Grumman, which provides range and bearing data, along with the mast-mounted AN/BLQ-10 electronic support measures (ESM) system from Lockheed Martin Integrated Systems.
AN/BLQ-10 provides full spectrum radar processing, automatic threat warning and situation assessment.
Because of the low rate of Virginia production, the Navy entered into a program with DARPA to overcome technology. barriers to lower the cost of attack submarines so that more could be built, to maintain the size of the fleet.
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