In need of a replacement for the ageing Los Angeles-class attack submarines and as a result of the unaffordable cost of building enough Seawolf-class submarines to replace them, in February 1991 the US Navy began designing a new class of more affordable attack submarines. The result would be the Virginia-class boats, the first in the US Navy to be designed entirely by computer.
The US Navy decided to divide construction of the Virginia-class submarines between Huntington Ingalls Industries Newport News Shipbuilding and General Dynamics Electric Boat. A primary aim of this arrangement was to reduce the financial cost of building the Virginia-class boats to a relatively low annual rate in the two shipyards, thus preserving critical submarine-construction skills and the resources at both locations.
Initial plans called for the US Navy to take forty-eight Virginia-class submarines into service by 2043. However, the number as of 2019 was thirty examples, with the expectation that this could be increased in the future.
The first Virginia-class submarine received its commissioning in October 2004 with the hull classification number SSN-774. As of the end of 2019, the US Navy has sixteen examples in service with their hull classification numbers in numerical sequence. These sixteen consist of three blocks, with each block representing a progressively-improved version of the vessel.
The Virginia-class submarines have a surface displacement of 8,700 tons and a length of 377ft. The US Navy lists their submerged top speed as 25 knots or more and test depth of 800ft. Respected sources suggest the submarine’s top speed is 35 knots and test depth 1,600ft. Weaponry is configurable based on mission requirements and ranges from torpedoes to Tomahawk cruise missiles as well as mines.
Rather than a single propeller, the Virginia-class submarines have a pump jet propulsor system (water jet) that had first appeared on the Seawolf-class submarines. One of the key advantages of a pump jet propulsor system for submarines is that the jets are quieter than propellers. The US Navy’s newest versions of its torpedoes also use a pump jet propulsor system.
Some of the state-of-the-art design features that came with the Virginia-class submarines appear in this passage from an online US Navy fact file:
The Virginia class has several innovations that significantly enhance its warfighting capabilities with an emphasis on littoral operations. Virginia class SSNs have a fly-by-wire ship control system that provides improved shallow-water ship handling . . . In Virginia-class SSNs, traditional periscopes have been supplanted by two photonics masts that host visible and infrared digital cameras atop telescoping arms. With the removal of the barrel periscopes, the ship’s control room has been moved down one deck and away from the hull’s curvature, affording it more room and an improved layout that provides the commanding officer with enhanced situational awareness.
The Virginia-class boats, beginning with the Block V model, will have an additional mid-body section referred to as the Virginia Payload Module (VPM). It contains four large-diameter, vertical launch tubes to store and fire additional Tomahawk cruise missiles or other payloads, such as large-diameter unmanned underwater vehicles (UUVs).
The Ohio-class submarines were designed for an intended forty-two-year lifespan, meaning that the first boat in the class constructed is due to be decommissioned in 2027. The US Navy wants to have the first of twelve planned replacement submarines ready at the same time. A number of options received consideration, as are detailed in this passage from an October 2106 report by the Congressional Research Service:
Over the last five years, the US Navy – working with U.S. Strategic Command, the Joint Staff and the Office of the Secretary of Defense – has formally examined various options to replace the Ohio ballistic missile submarines as they retire beginning in 2027. This analysis included a variety of replacement platform options, including designs based on the highly successful Virginia-class attack submarine program and the current Ohio-class ballistic missile submarine. In the end, the US Navy elected to pursue a new design that leverages the lessons from Ohio, the Virginia advances in shipbuilding and improvements in cost-efficiency.
That new submarine class acquired the name Columbia. It will be the same length as that of the Ohio class. Its estimated surface displacement as of 2014 is 20,815 tons. The yet-to-be-built submarines will have accommodation for a crew of up to 155 personnel. It will also come with a turbo-electric propulsion system.
Unlike the Ohio-class submarines that required a mid-life nuclear refuelling, the nuclear reactors on the Columbia class will last the lifespan of the boats themselves, intended to be forty years. Instead of the twenty-four SLBM launch tubes found on the Ohio class, the Columbia class will have only sixteen SLBM launch tubes in addition to torpedo tubes.
As it has with the Virginia-class submarines, the US Navy intends that both Huntington Ingalls Industries Newport News Shipbuilding and General Dynamics Electric Boat be involved with the building of the planned Columbia class. The construction work was assigned to General Dynamics Electric Boat as of the end of 2018.
An artist’s impression of the Virginia-class attack submarine before the design and construction phase began. Note that it features the same streamlined sail design as the Seawolf-class attack submarines. As of 2019 seventeen examples of the Virginia class were in US Navy service with nine under construction and two on order with more planned for the future. (US Navy)
Inside a General Dynamics Electric Boat assembly building is seen a Virginia-class attack submarine under construction. All are also referred to as the ‘SSN-774’ class after the hull classification number on the first boat built. The Virginia class is supposed to be the affordable replacement for the Los Angeles-class attack submarine that the Seawolf class did not prove to be, resulting in only three constructed. (US Navy)
At a certain point in the process, General Dynamics Electric Boat moves a submarine under construction outside, as is seen here with a Virginia-class attack submarine. Reflecting the ever-continuing pace of modern technology, the Virginia class has several new features not seen on the previous Los Angeles class. These include a fly-by-wire ship control system that provides improved shallow-water handling. (US Navy)
From the beginning, the US Navy has sought various methods of keeping costs down on the Virginia-class attack submarine. These include use of as many off-the-shelf commercial electronic components as possible, rather than programme-developed specialized and more expensive counterparts. Pictured here is the control room on a Virginia-class boat. (US Navy)
In this image of the sail of a Virginia-class attack submarine, we see the two telescoping photonics masts that contain both visible and infrared digital cameras as well as a laser range-finder that have replaced traditional periscopes. Unlike the latter, the photonics masts do not penetrate the submarine’s hull, allowing for the control station to be moved to a roomier location deeper within the pressure hull. (US Navy)
Pictured here are two of the four 21in-diameter torpedo tubes on the Virginia-class attack submarines. As was established with the Sturgeon-class attack submarines, they are located behind the bow sonar compartment and are angled outward from the hull. Torpedo-loading was more mechanized than in the past, using power-operated devices. The Virginia class had storage space for thirty-seven torpedoes. (US Navy)
The first ten examples of the Virginia-class attack submarine that fell under the heading of Block I and II models were armed with the Vertical Launch System (VLS) for twelve Tomahawk missiles. Starting with the Block III model of the Virginia class, the US Navy had the VLS replaced with two large 87in Virginia Payload Tubes (VPTs), as seen here with two tubes’ hydraulically-operated door fully opened. (US Navy)
Besides their nuclear reactors, all US Navy nuclear-powered submarines have a back-up diesel engine in case the reactor has to go down for any reason. The engines are a smaller version of the Fairbanks-Morse (FM) diesel engine that drove many of the US Navy fleet boats during the Second World War. Pictured here are crewmen of a Virginia-class attack submarine checking the status of their diesel engine. (US Navy)
At the very low end of technology in the Virginia-class attack submarines are two of the more mundane pieces of equipment seen here: an electrically-powered washing machine and dryer. The submarines have an advanced filtration system and dehumidifiers to maintain not only crew habitability but also optimum conditions for the onboard electronics. (US Navy)
Despite the ever-increasing size of US Navy submarines over a century, living quarters for enlisted personnel remain coffin-sized, as seen in this photograph taken inside a Virginia-class attack submarine. They are indeed better than the open bunks of Second World War fleet-type boats, with blowers for fresh air, reading lights, bedding and curtains to block most light. (US Navy)