Navy races to bolster its attack submarine fleet, leveraging advanced Virginia-class technology to meet critical combatant commander demands.
by Kris Osborn, Warrior Maven
The U.S. Navy is surging to add as many new Virginia-class attack submarines as quickly as possible, something which has been on the services’ radar for many years. As Los Angeles submarines retire and Columbia-class nuclear-armed ballistic missiles submarines begin construction, the U.S. Navy has for years been aware of its “submarine deficit,” meaning there simply are not enough operational attack submarines to accommodate combatant commander demand. This is particularly true in areas such as the Pacific, given that U.S. Navy undersea superiority could potentially “save” Taiwan from a surprise Chinese amphibious assault. Surface ships, drones and ground defenses supporting Taiwan would easily be seen by PLA sensors, satellites and drones, yet secret, quite Virginia-class submarines could potentially lurk undetected in position to destroy PLA Navy surface ships transiting the Taiwan strait.
This is why the Navy is quick to highlight and celebrate its newest addition to the Virginia-class attack submarine fleet, with the commissioning of the USS Idaho SSN 799 advanced Block IV boat.
The U.S. Navy has thus far built eight Block IV Virginia-class attack submarines, a crucial “bridge” step between Block III and the upgunned Block V with Virginia Payload Modules. While Block IV does not add 28 more Tomahawks and a 79ft extended hull for the additional weaponry, it does build upon and advance technologies integrated into Block III Virginia-class submarines. Secondly, Block IV incorporates a new series of technological upgrades surged into existing Block III submarines which include additional quieting coating materials, antennas for improved connectivity, among other things.
Spy Submarines
Block III was built with a breakthrough Large Aperture Bow sonar, something designed to enable longer range active and passive detection. The integration of this LAB massively expanded the undersea surveillance capacity of the boats, a technological dynamic which inspired commanders to think of the boats as being more capable of undersea ISR. Virginia attack submarines can increasingly “loiter” quietly in high-risk coastal areas to conduct clandestine reconnaissance missions. These special Block III upgrades were built into a prototype submarine years ago called the USS North Dakota; the success of the integration effort inspired the service to upgrade its entire fleet of Block III Virginia-class submarines with the added technologies. It stands to reason that these upgrades would extend into even more capable Block IV boats. Block IV Virginias build upon this ISR capacity and surge its capacity into a new realm, something designed to further enable quiet threat detection.
Supporting special operations is central to this concept of operation, as Block III submarines operate with what’s called a Lock out Trunk, a “dry” area which then fills up with water to allow Special Operations Forces to exit the submarine for secret missions without having to surface. This greatly improves survivability for SOF missions as they regularly conduct secret reconnaissance, hostage rescue or targeted attack missions behind enemy lines.
Virginia Computing
The largest innovation woven into Block III is the “fly-by-wire” computer technology which uses automation and advanced algorithms to navigate speed, depth, angle and trajectory in coordination with ship-integrated sensors to avoid collision and follow an optimal course. A human commander can set depth and speed and remain operative in a command and control capacity, yet advanced computing can greatly assist navigation by making slight adjustments autonomously as needed.
Yet another advantage with the Virginia submarines is its diesel electric engine, a propulsion technology which “powers” the ship and adds an additional on-board power generation capability. This is quite helpful given that Block III and Block IV operate with a much higher degree of power requirements, given the fiber-optical cables for reconnaissance, added computing and on-board electronics. Electricity is also needed to analyze the sonar return images generated by the enlarged sonar
Navy Seeks Faster Submarine Building
At several points in recent years, the US Navy commissioned and launched specific industrial base studies to assess industry’s ability to “flex” to accommodate the need to build two Virginia-class submarines every years when the Columbia-class begins to emerge. At several points Navy decision makers and Congressional appropriators even outlined an ambitious plan to try to build “three” Virginia-class submarines per year.
The Navy has “procured” two Virginia-class boats at a rate of two per year since 2011, yet the service and its industrial partners have not been able to build the submarines at this pace since 2019, a circumstance which has in recent years greatly exacerbated the service’s submarine deficit problem. As of mid 2025, the US Navy operated 19 Virginia-class boats and 29 Los Angeles-class submarines, according to Embleholics, yet the Navy has for many years hoped it could operate a fleet of as many as 50 Virginia-class attack subs by the mid 2040s, according to its 2016 30-year shipbuilding plan.
The US Navy’s 2025 “30-Year Shipbuilding Plan” states the service plans to again build two Virginias per year by 2028 Virginia-class submarines are built by a cooperative arrangement between the Navy and Electric Boat, a subsidiary of General Dynamics and Newport News Shipbuilding, a division of Huntington Ingalls Industries. Each industry partner constructs portions, or “modules,” of the submarines which are then melded together to make a complete vessel
. Kris Osborn is the Military Technology Editor of 1945. Osborn is also President of Warrior Maven – Center for Military Modernization. Osborn previously served at the Pentagon as a highly qualified expert in the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University--