Virginia-class submarine


The Virginia class, or the SSN-774 class, is a class of nuclear-powered attack submarine with cruise missile capability in service with the United States Navy. The class is designed for a broad spectrum of open-ocean and littoral missions, including anti-submarine warfare and intelligence gathering operations. They are scheduled to replace older Los Angeles-class attack submarines, many of which have already been decommissioned, as well as four cruise missile submarine variants of the Ohio-class submarines. Upon the 25 July 2025 decommissioning of the Los Angeles-class submarine USS Helena, the Virginia-class became the most numerous active submarine class in the world.
Virginia-class submarines will be acquired through 2043, and are expected to remain in service until at least 2060, with later submarines expected to operate into the 2070s.
On 14 March 2023, the trilateral Australian-British-American security pact known as AUKUS announced that the Royal Australian Navy would purchase three Virginia-class submarines as a stopgap measure between the retirement of their conventionally powered s and the acquisition of the future SSN-AUKUS class submarines. If SSN-AUKUS falls behind schedule, Australia will have the option of purchasing two additional Virginia-class submarines.

History

The class was developed under the codename Centurion, later renamed New SSN. The "Centurion Study" was initiated in February 1991. The Virginia-class submarine was the first US Navy warship with its development coordinated using such 3D visualization technology as CATIA, which comprises computer-aided engineering, computer-aided design, computer-aided manufacturing, and product lifecycle management. Design problems for Electric Boat—and maintenance problems for the Navy—ensued nonetheless.
By 2007 approximately 35 million labor hours had been spent to design the Virginia class. Constructing a single Virginia-class submarine has required around nine million labor hours, and over 4,000 suppliers. Each submarine is projected to make 14–15 deployments during its 33-year service life.
The Virginia class was intended in part as a less expensive alternative to the , whose production run was canceled after just three boats had been completed. To reduce costs, the Virginia-class submarines use many "commercial off-the-shelf" components, especially in their computers and data networks. Improvements in shipbuilding technology have trimmed production costs below the $1.8 billion projected fiscal year 2009 dollars.
In hearings before both House of Representatives and Senate committees, the Congressional Research Service and expert witnesses testified that the annual procurement rate of only one Virginia-class boat—rising to two in 2012—would result in excessive unit production costs, yet an insufficient complement of attack submarines. In a 10 March 2005 statement to the House Armed Services Committee, Ronald O'Rourke of the CRS testified that, assuming that the production rate remains as planned, "production economies of scale for submarines would continue to remain limited or poor."
In 2001, Newport News Shipbuilding and the General Dynamics Electric Boat Company built a quarter-scale version of a Virginia-class submarine dubbed Large Scale Vehicle II Cutthroat. The vehicle was designed as an affordable test platform for new technologies.
The Virginia class is built through an industrial arrangement designed to maintain both GD Electric Boat and Newport News Shipbuilding, the only two U.S. shipyards capable of building nuclear-powered submarines. Under the present arrangement, the Newport News facility builds the stern, habitability, machinery spaces, torpedo room, sail, and bow, while Electric Boat builds the engine room and control room. The facilities alternate work on the reactor plant as well as the final assembly, test, outfit, and delivery.
O'Rourke wrote in 2004 that, "Compared to a one-yard strategy, approaches involving two yards may be more expensive but offer potential offsetting benefits." Among the claims of "offsetting benefits" that O'Rourke attributes to supporters of a two-facility construction arrangement is that it "would permit the United States to continue building submarines at one yard even if the other yard is rendered incapable of building submarines permanently or for a sustained period of time by a catastrophic event of some kind", including an enemy attack.
To get the submarine's price down to $2 billion per submarine in FY-05 dollars, the Navy instituted a cost-reduction program to shave off approximately $400 million of each submarine's price tag. The project was dubbed "2 for 4 in 12", referring to the Navy's desire to buy two boats for $4 billion in FY-12. Under pressure from Congress, the Navy opted to start buying two boats per year in FY-11, meaning that officials would not be able to get the $2 billion price tag before the service started buying two submarines per year. However, program manager Dave Johnson said at a conference on 19 March 2008 that the program was only $30 million away from achieving the $2 billion price goal, and would reach that target on schedule.
The Virginia-class Program Office received the David Packard Excellence in Acquisition Award in 1996, 1998, and 2008 "for excelling in four specific award criteria: reducing life-cycle costs; making the acquisition system more efficient, responsive, and timely; integrating defense with the commercial base and practices; and promoting continuous improvement of the acquisition process."
In December 2008, the Navy signed a $14 billion contract with General Dynamics and Northrop Grumman to supply eight submarines. The contract required the delivery of one submarine in each of fiscal 2009 and 2010, and two submarines on each of fiscal 2011, 2012, and 2013. This contract was designed to bring the Navy's Virginia-class fleet to 18 submarines. In December 2010, the United States Congress passed a defense authorization bill that expanded production to two subs per year. Two submarine-per-year production resumed on 2 September 2011 with commencement of construction.
On 21 June 2008, the Navy christened, the first Block II submarine. This boat was delivered eight months ahead of schedule and $54 million under budget. Block II boats are built in four sections, compared to the ten sections of the Block I boats. This enables a cost saving of about $300 million per boat, reducing the overall cost to $2 billion per boat and the construction of two new boats per year. Beginning in 2010, new submarines of this class were to have included a software system that can monitor and reduce their electromagnetic signatures when needed.
The first full-duration six-month deployment was successfully carried out from 15 October 2009 to 13 April 2010. Authorization of full-rate production and the declaration of full operational capability was achieved five months later. In September 2010, it was found that urethane tiles, applied to the hull to damp internal sound and absorb rather than reflect sonar pulses, were falling off while the subs were at sea. Admiral Kevin McCoy announced that the problems with the Mold-in-Place Special Hull Treatment for the early subs had been fixed in 2011, then Minnesota was built and found to have the same problem.
In 2013, just as two-per-year sub construction was supposed to commence, Congress failed to resolve the United States fiscal cliff, forcing the Navy to attempt to "de-obligate" construction funds.
In April 2019, the CRS reported that the Navy estimated the cost of a boat was $2.8 billion. In July 2023, the CRS reported that the Navy estimates at the present production rate of two boats per year that the cost per boat when equipped with the additional Virginia Payload Module mid-body section was $4.3 billion.
On 14 September 2023, at a Senate confirmation hearing, Admiral Lisa Franchetti said that the US Navy would have to work with builders to raise the rate of production from 1.2/year to 2.2/year to meet the AUKUS target.

Innovations

The Virginia class incorporates several innovations not found in previous US submarine classes.

Technology barriers

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.
These include:
  • Propulsion concepts not constrained by a centerline shaft.
  • Externally stowed and launched weapons.
  • 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

    Unified Modular Masts

Virginia-class subs are the first class where all masts share common design – the Universal Modular Mast – designed by L3 KEO. Shared components have been maximized and some design choices are also shared between different masts. The first UMM was installed on, a Los Angeles-class submarine. The UMM is an integrated system for housing, erecting, and supporting submarine mast-mounted antennas and sensors. The UMMs are the following:
  • Snorkel mast
  • Two photonic masts
  • Two communication masts
  • One or two high-data-rate satellite communication masts, built by Raytheon, enabling communication at super high frequency and extremely high frequency range
  • Radar mast
  • Electronic warfare mast used to detect, analyze, and identify both radar and communication signals from ships, aircraft, submarines, and land-based transmitters

    Photonics masts

The Virginia class is the first to utilize photonic sensors instead of a traditional periscope. The class is equipped with high-resolution cameras, along with light-intensification and infrared sensors, an infrared laser rangefinder, and an integrated Electronic Support Measures array. Two redundant sets of these sensors are mounted on two AN/BVS-1 photonics masts located outside the pressure hull. Signals from the masts' sensors are transmitted through optical fiber data lines through signal processors to the control center. Visual feeds from the masts are displayed on liquid-crystal display interfaces in the command center.
The design of earlier optical periscopes required them to penetrate the pressure hull, reducing the structural integrity of the pressure hull as well as increasing the risk of flooding, and also required the submarine's control room to be located directly below the sail/fin. Implementation of photonics masts enabled the submarine control room to be relocated to a position inside the pressure hull which is not necessarily directly below the sail.
The current photonics masts have a visual appearance so different from ordinary periscopes that when the submarine is detected, it can be distinctly identified as a Virginia-class vessel. As a result, current photonic masts will be replaced with Low-Profile Photonics Masts which resemble traditional submarine periscopes more closely.
In the future, a non-rotational Affordable Modular Panoramic Photonics Mast may be fitted, enabling the submarine to obtain a simultaneous 360° view of the sea surface.