History
In September of 1998 the USS Virginia (SSN774) was ordered as the lead submarine of a new class of nuclear powered fast attack submarines. Her keel was laid down in September of 2000 at the general Dynamics Electric Boat shipyard in Groton, CT and she was later launched in August in 2005. The Virginia was commissioned in October of 2005.
The Virginia class submarines are the first class of submarine to be designed and influenced by post-Cold War needs. With the emphasis no longer on open ocean SLOC (Sea Lanes of Communication) warfare against the Warsaw Pact, the Virginia, though still capable of traditional "blue water" deep ocean missions, focuses on "littoral" missions, specifically special operations support, intelligence gathering, and counter mine operations. While it carries the same weapons as its Cold War predecessors (the Seawolf class and Los Angeles class attack submarines) its weapon loadout is significantly smaller (roughly half that of the Sea Wolf.) In addition, where the Seawolf featured eight 660mm "swimout" low transient signature torpedo tubes, the Virginia is armed with only four conventional 533mm tubes. The Virginias however, are the first class of submarine specifically built to incorporate the regular use of ROV sensors.
The reduced size and weapons capability, as well as the incorporation of commercial off the shelf (COTS) equipment for its data processors and related systems, was intended to make the Virginia a cheaper alternative compared to the Seawolf ($1.8B vs. $2.0B. Unfortunately, the realized cost of each Virginia class submarine is now expected to be closer to $2.3B because of an unrealized economy of scale production benefit (Since the Navy is not building the submarines fast enough, they are costing more.)
To date, three Virginia class submarines have been commissioned into active service. An additional six are either on order or under construction. The Navy expects to purchase at least 30 submarines of this class. Construction of these submarines is split between Electric Boat in Groton, and the Northrop Grumman Newport News Shipbuilding facility in Newport News.
Description
General Characteristics:
The Virginia class fast attack submarines are 377 feet long, have a beam of 34 feet, and draw 32 feet of water (surfaced.) Their full load displacement is 7,800 tons submerged. Ship's compliment is 134 officers and enlisted. The Virginia class submarines have a top speed of 25 knots on the surface and a submerged speed of more than 32 knots. The maximum diving depth is in excess of 800 feet. Because the reactor in the Virginia class submarines is designed to outlive the useful life of the hull, the operational range of these submarines is effectively unlimited.
To support SOC operations, the Virginia class submarines are capable of transporting and launching both the DDS (dry deck shelter) and the SDV (SEAL delivery vehicle). These submarines are also equipped with a 9-man diver lock out chamber for rapid deployment of swimmers directly from the submarine.
The Virginia class submarines are the first class of American submarine to be equipped with a non-hull penetrating fiber-optic periscope system. The Virginia is equipped with two Kollmorgen BVS-1 photonic masts. In addition to the standard daylight optic capabilities of traditional periscopes, the photonic masts will also incorporate LLTV (Low Light TV), thermal imaging, and laser rangefinding capabilities.
To reduce the submarine?s noise signature, the various compartments are fitted with isolated deck modules, where components are mounted as a single unit on a spring isolated platform, thus eliminating vibration related noise from radiating out through the hull or axially between compartments.
Propulsion:
The Virginia class submarines are powered by a single General Electric S9G nuclear reactor producing 40,000 horsepower. Propulsion is provided by two steam turbines connected to a single shaft with shrouded pumpjet propulsor.
Electronics:
The Virginia class submarines are equipped with a bow-mounted spherical active and passive sonar array, a wide aperture lightweight fiber optic sonar array (this system actually consists of three flat panels mounted on each side of the submarine hull), as well as keel and fin mounted high frequency active sonar arrays. In addition, the submarines are equipped with two towed sonars, the TB-16 ?fat line? towed array and the TB-29 low frequency ?thin line? towed array. Sonar data is processed through the BQQ-10(v)4 sonar processing system.
For surface navigation, the Virginia uses a BPS-16(v)4 I-band navigation radar.
Command and control systems include the BYG-1(v) combat information management system which also provides weapon control capabilities as well. The Virginias are also equipped with two mast-mounted Submarine High Data Rate satellite communications systems that allow simultaneous communication at Super High Frequency (SHF) and Extremely High Frequency (EHF).
Defensive and electronic warfare systems include the WLY-1 acoustic countermeasures system (an automated threat torpedo detection, classification and tracking system) and the BLQ-10 advanced submarine tactical electronic warfare system.
Armament:
The Virginia class submarines are armed with a twelve VLS tubes mounted forward of the sail. These tubes may be fitted with a variety of mission-oriented weapons, to include tomahawk cruise missiles. In addition, the Virginia is equipped with four 533mm (21?) torpedo tubes. Each submarine can carry a total of 26 tube-launched weapons; Mk48 mod 6 ADCAP heavyweight torpedoes, mk50 lightweight ASW torpedoes, sub-launched Harpoon antiship missiles, or Mk60 CAPTOR mines.
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