US Navy Receives first Virginia-class Block IV Nuclear-Powered Attack Submarine

The United States Navy took the delivery of $3billion Vermont (SSN 792), its first Virgnia-class Block IV nuclear-powered attack submarine, on Friday.

“Vermont is the 19th Virginia-class submarine of the US Navy. It is the first of the ten-ship group of Virginia-class submarines known as Block IV. These ships embody a Navy and industry commitment to affordably deliver new submarines to the fleet with unmatched stealth and strike capacity,” General Dynamics Electric Boat, that built the boat, said in a statement on April 17.

Virginia-class submarines:

Virginia-class submarines displace 7,835 tons, with a hull length of 377 feet and a diameter of 34 feet. They are capable of speeds in excess of 25 knots and can dive to a depth greater than 800 feet, while carrying Mark 48 advanced capability torpedoes and Tomahawk cruise missiles.

This class of fast-attack submarines were being built to replace the ageing Los Angeles-class boats. The ships are equipped with 12 twelve Vertical Launch System (VLS) tubes, 4 torpedo tubes, Mk 48 ADCAP Torpedoes, UGM-109 Tomahawk cruise missiles, Mk 60 CAPTOR mines, advanced mobile mines, and unmanned underwater vehicles.

During their 33-year service life, Block I-III submarines will have to undergo four depot maintenance availabilities and conduct 14 deployments. Block IV design changes will reduce the planned depot maintenance availabilities to three and increase deployments to 15.

Block V: The 84-foot Block V submarines built will have additional Virginia Payload Module (VPM) mid-body section, increasing their overall length. The VPM is designed to triple the Tomahawk cruise missile capacity of the Virginia-class subs, a move designed to offset the pending retirement of the Ohio-class guided-missile subs, which have a 154-Tomahawk capacity. Each VPM sub will have a 40-Tomahawk loadout.