The US Navy’s 13th Virginia-class attack submarine USS Illinois (SSN-786) has successfully completed its first at-sea evaluations, also called alpha sea trials, and sailed back to the General Dynamics Electric Boat shipyard.
The alpha sea trials validated the mission capability of the vessel’s propulsion plant through a range of submarine and propulsion-plant operations, submerging for the first time and high-speed runs on and below the surface.
Electric Boat president Jeffrey Geiger said: "The crew and shipbuilders worked together seamlessly to take this submarine to sea and put it through its paces.
"It was a superb effort by everyone involved, and reflects the commitment of the navy and industry team to sustain the success of the Virginia-class submarine programme.
“I deeply appreciate the contributions made by the navy personnel, shipbuilders and suppliers who made it happen."
USS Illinois was christened by the First Lady of the US, Michelle Obama, in October 2015.
The US Navy has already received 12 Virginia-class submarines from Electric Boat, along with its construction partner Huntington Ingalls Industries (HII) Newport News Shipbuilding, with 15 more vessels of the class under contract.
The submarines have a hull length of 377ft, diameter of 34ft and a displacment capacity of 7,835t.
Equipped with Mark 48 advanced capability torpedoes and Tomahawk land-attack missiles, the vessels can operate at a speed of more than 25k and can stay underwater at a depth of more than 800ft.
The boats can be deployed to engage in anti-submarine, anti-surface ship and counter-mine warfare, as well as support surveillance, special operations and covert strike missions.
Image: USS Illinois completes alpha sea trials. Photo: courtesy of PRNewsFoto/General Dynamics Electric Boat.