The US Navy has awarded $1.2bn to General Dynamics (GD) Electric Boat for the construction of the 14th Virginia Class submarine, SSN-787.
The contract also marks the start of production of two submarines a year, and the procurement of long-lead-time components on the Virginia Class programme.
The Virginia Class submarines have been designed to play a crucial role in the nation's defence with maximum technological and operational flexibility, stealth, firepower and unlimited endurance.
The 377ft-long, 7,800t submarines are capable of cruising at speeds of 25kt and can carry mk48 advanced capability torpedoes, Tomahawk land attack missiles and unmanned underwater vehicles.
Construction of the submarines will take place at Electric Boat and Huntington Ingalls Industries in Newport News, Virginia, US.