General Dynamics and HII Virginia-class Block VI

History

The Virginia-class Block VI is a planned group of nuclear-powered submarines for the United States Navy. General Dynamics Electric Boat and HII Newport News Shipbuilding received contracts for nine boats in July 2026 after beginning long-lead material procurement earlier that year.

Block VI retains the enlarged Virginia Payload Module configuration introduced with Block V. Its planned improvements emphasize acoustic performance, sonar processing, seabed warfare and the integration of unmanned underwater systems.

The Virginia Payload Module gives each submarine 40 vertical weapon positions, compared with 12 aboard earlier Virginia-class blocks. In August 2026, the Navy announced that Virginia-class submarines equipped with this module would be reclassified from attack submarines to guided-missile submarines.

Development of the Virginia class

Construction of the first Virginia-class submarine began in 1999. USS Virginia entered service on October 23, 2004. The class was developed as a modular, multipurpose replacement for older Los Angeles-class attack submarines.

Block II reduced the number of major construction modules from ten to four. Block III introduced the Large Aperture Bow sonar and replaced 12 individual vertical-launch cells with two large Virginia Payload Tubes. Block IV reduced the number of planned major maintenance periods during a 33-year service life from four to three, increasing the planned number of deployments from 14 to 15.

Block V introduced the Virginia Payload Module, an additional mid-body section containing four large payload tubes. This change increased the hull length and restored part of the underwater strike capacity expected to disappear when the four Ohio-class guided-missile submarines retire.

Block VI procurement

Congress appropriated $3.6 billion for USS Potomac in fiscal year 2025 and provided advanced procurement funding for later boats. On May 11, 2026, the Navy awarded a $2.306 billion preliminary contract modification covering long-lead materials and early Block VI manufacturing. The funded items included nuclear and propulsion equipment that requires several years to produce.

A multiyear procurement certification was signed in June 2026 and completed the following month. It supported the planned purchase of nine submarines and projected savings of approximately $2.4 billion compared with separate annual orders.

On July 29, 2026, the Navy awarded $42.1 billion for nine Block VI submarines and material for a possible tenth boat. The award was part of a combined $76.6 billion package that also covered five Columbia-class ballistic-missile submarines and shipyard productivity investments. The contracts apply to Virginia-class boats funded from fiscal years 2025 through 2029. Details were reported by USNI News and Naval News.

The first three announced Block VI boats are USS Potomac, numbered SSN-814 when named; USS Norfolk, SSN-815; and USS Brooklyn, SSN-816. Potomac was expected to enter service in 2034 or 2035 if the planned schedule could be maintained.

Design

Hull and construction

Block VI retains the enlarged hull configuration used by Virginia Payload Module-equipped Block V submarines rather than introducing an entirely new design. The submarine is approximately 140 m long and displaces about 10,200 tonnes when submerged. Earlier Blocks I through IV are approximately 115 m long and displace about 7,900 tonnes submerged.

The increase results primarily from the approximately 25.6 m Virginia Payload Module inserted between the operations compartment and propulsion spaces. The module provides additional internal volume and four large-diameter payload tubes.

Construction is divided between General Dynamics Electric Boat and HII Newport News Shipbuilding. Newport News manufactures the bow, stern, sail, torpedo room, habitability spaces and other modules. Electric Boat builds major command, machinery and propulsion-related sections. The yards alternate responsibility for reactor work, final assembly, outfitting, testing and delivery.

This arrangement maintains two American nuclear-submarine construction centers but creates dependencies between their schedules. Delayed or incomplete modules, shortages of nuclear-qualified workers and supplier backlogs can affect final assembly at either yard.

Propulsion and control

The design uses an S9G nuclear reactor connected to a single shaft and a low-noise pump-jet propulsor. Nuclear propulsion provides sustained underwater operation without the frequent refuelling or battery-charging requirements of conventionally powered submarines.

The Virginia class uses a fly-by-wire ship-control system in place of traditional mechanical or electro-hydraulic control arrangements. Photonics masts carry optical, low-light and infrared sensors without penetrating the pressure hull like a conventional optical periscope. This permits the control room to be positioned independently of the sail.

Sensors and mission systems

Virginia-class sonar equipment includes a bow array, wide-aperture flank arrays, high-frequency arrays for coastal and under-ice navigation and tactical and long-range towed arrays. Its open-system architecture allows processors and software to be updated without replacing the entire combat system.

Block VI changes are expected to include improvements in acoustic quieting, propulsion equipment, sonar processing and undersea sensors. Available information also associates the block with expanded seabed-warfare capabilities and improved support for unmanned underwater vehicles. Specific configurations have not been publicly defined for every boat.

At least one Block VI submarine is expected to receive specialized equipment for seabed missions associated with the role performed by USS Jimmy Carter. Such work can include intelligence collection, operating near fixed undersea infrastructure and deploying equipment while submerged. The usefulness of unmanned vehicles in these missions will depend on their launch and recovery systems, storage, maintenance, communications and data-processing facilities.

Payload and armament

The Virginia Payload Module contains four large-diameter tubes. Each tube can accommodate seven Tomahawk cruise missiles, providing 28 vertical positions. Two Virginia Payload Tubes in the bow can each hold six missiles, producing a maximum total of 40 vertical weapon positions.

The submarine also retains four 533 mm torpedo tubes for Mk 48 heavyweight torpedoes, mines and compatible tube-launched weapons. The figure of 40 therefore describes vertical payload capacity rather than the submarine's complete weapon load.

The large tubes may also carry unmanned underwater vehicles, sensors or future large-diameter payloads. Actual missile capacity consequently depends on the mission load. Block VI is expected to be the second Virginia-class block capable of carrying the Navy's planned long-range hypersonic strike weapon.

Program status

Block VI entered its industrial phase in 2026, but no completed submarine had yet entered service. Long-lead work under the preliminary award was scheduled to continue through September 2035, while delivery of Virginia Payload Module-equipped Block V and Block VI submarines was planned to continue through 2038.

In August 2026, the Navy announced that 19 planned Virginia-class submarines equipped with the payload module would be redesignated as guided-missile submarines. The change applies to qualifying Block V and Block VI boats and reflects their increased strike capacity. It does not indicate that the unfinished Block VI submarines had become operational. The reclassification was described by Navy Times.

The principal program risk is industrial capacity. Virginia-class production was close to one boat per year in June 2025, below the Navy's objective of two boats per year and the higher rate associated with combined American and AUKUS requirements. Reported constraints include shortages of qualified welders, pipefitters, electricians, machinists and engineers, incomplete modules, rework, limited outfitting space and supplier delays.

The Columbia-class ballistic-missile submarine has priority when both programs require the same skilled labor, facilities or nuclear-certified components. The multiyear Block VI contract gives shipyards and suppliers more predictable demand, but delivery dates remain dependent on workforce expansion, productivity improvements and supply-chain performance.

Variants

• Virginia Block V: First block to introduce the enlarged hull and Virginia Payload Module. The module begins with the second Block V boat.
• Virginia Block VI: Follow-on configuration retaining the payload module while adding planned acoustic, sonar, propulsion, seabed-warfare and unmanned-system improvements.

Specifications (Virginia-class Block VI)

General characteristics

• Type: Nuclear-powered multipurpose submarine; planned Navy classification as a guided-missile submarine
• Builders: General Dynamics Electric Boat and HII Newport News Shipbuilding
• Length: Approximately 140 m
• Beam: Approximately 10.36 m
• Submerged displacement: Approximately 10,200 tonnes
• Crew: Approximately 135
• Propulsion: One S9G nuclear reactor, one shaft and one pump-jet propulsor

Performance

• Submerged speed: More than 25 knots

Armament and payload

• Bow payload tubes: Two Virginia Payload Tubes with six vertical weapon positions each
• Virginia Payload Module: Four large-diameter tubes with seven vertical weapon positions each
• Total vertical capacity: Up to 40 missiles when configured entirely for compatible cruise missiles
• Torpedo tubes: Four 533 mm tubes
• Supported payloads: Mk 48 heavyweight torpedoes, mines, Tomahawk cruise missiles and compatible unmanned or large-diameter payloads