US Navy transfers first Virginia Payload Module of USS Arizona submarine for final assembly.

General Dynamics Electric Boat transferred the first completed 184-foot Virginia Payload Module section for the future USS Arizona from Quonset Point, Rhode Island, to Groton, Connecticut. The 10,200-ton Block V submarine hull incorporates an 83-foot-long midships extension that houses four large-diameter payload tubes. This structural integration increases the vessel's vertical launch capacity to 40 Tomahawk-class or equivalent strategic munitions.

The integration of the Virginia Payload Module expands the Virginia-class submarine's length to 461 feet while increasing its vertical missile inventory by 233 percent over previous baseline configurations. This structural upgrade allows the vessel to field a maximum payload of 40 vertical-launch weapons, supporting future conventional strike and multi-mission deployment mandates.

Related topic: U.S. Navy and HII begin construction of Virginia-class Block V submarine Barb

The Virginia Payload Module (VPM) is an 84-ft-long hull extension containing four large-diameter payload tubes to increase the Virginia-class submarines' vertical missile capacity from 12 to 40 while also supporting future weapons and unmanned underwater systems. (Picture source: GDEB)

On September 15, 2026, General Dynamics Electric Boat transferred the first Virginia Payload Module (VPM) incorporated into a Virginia-class submarine toward final assembly, when the 184-ft Section 2B/5 of the future USS Arizona (SSGN-803) was displaced from Quonset Point, Rhode Island, to Groton, Connecticut. The section traveled aboard the Holland, Electric Boat's 400 × 100-ft self-ballasting ocean transport barge with a 5,500-ton payload capacity, and is the largest Virginia-class section transported to date. The USS Arizona will be the first Virginia-class fitted with the VPM, an 84-ft-long (25.6 m) extension, which increases hull length from 377 ft (114.8 m) to 461 ft (140.5 m) and submerged displacement from 7,800 to 10,200 tons, while beam remains 34 ft (10.36 m). With four large-diameter VPMs carrying up to seven Tomahawks each and two Virginia Payload Tubes (VPTs) carrying 12, the USS Arizona's vertical launch capacity also increases from 12 to 40 missiles. The USS Arizona was keel-authenticated at Quonset Point on December 7, 2022, and is currently scheduled for delivery in July 2029, followed by operational testing beginning in September 2029.

The Virginia Payload Module (VPM) is an additional pressure-hull section that will increase the Virginia-class submarine length by 22.3% and submerged displacement by 30.8% (2,400 tons), while retaining the 34-ft beam, nuclear propulsion arrangement, single shaft, and four 21-in torpedo tubes. The four VPM tubes provide 28 Tomahawk positions, while the two 87-in bow VPTs introduced with Block III submarines retain another 12, meaning the USS Arizona has six large-diameter payload tubes arranged for 6 + 6 + 7 + 7 + 7 + 7 missiles rather than 40 individual cells. Total capacity for torpedo-sized weapons also increases from roughly 37 to 65, a 75.7% rise. At 461 ft and 10,200 tons submerged, a VPM-equipped Virginia submarine represents 82.3% of an Ohio SSGN's 560-ft length but only 54.4% of its 18,750-ton submerged displacement.

The 40-round vertical magazine that led to the VPM results from two successive Virginia-class weapon changes. Blocks I and II submarines carried 12 individual Tomahawk launch tubes; the Block III replaced them with two 87-in VPTs carrying six missiles each, preserving the total of 12 weapons while reducing the number of launch interfaces from 12 to two. Now, the VPM adds four seven-round tubes amidships, increasing vertical capacity by 28 weapons (233.3%), 3.33 times the Block III and IV level. The VPM consequently contains 70% of the submarine's maximum vertical Tomahawk load, with the bow VPTs accounting for 30%, while the four 21-in torpedo tubes and torpedo-room weapons remain separate. The principal conventional strike weapon for the VPM is the Tomahawk Block V, with an official range of 900 nmi (1,600 km); the Block Va Maritime Strike Tomahawk is optimized for naval targets, and the Block Vb incorporates the Joint Multiple Effects Warhead System.

The Ohio comparison shows why the VPM replaces strike capacity across multiple hulls rather than replacing each retiring SSGN individually. An Ohio SSGN can carry seven Tomahawks in 22 former Trident ballistic missile tubes for a total of 154 missiles, producing a theoretical maximum of 616 Tomahawk vertical-launch positions across four boats. One Virginia SSGN carrying 40 vertically launched Tomahawks therefore provides only 26% of one Ohio's maximum missile capacity, meaning an Ohio still carries 3.85 times the vertical launch capacity of a VPM Virginia. Consequently, four VPM-equipped Virginias provide 160 Tomahawk launch tubes, eight provide 320, 12 provide 480, and 15 provide 600, still 16 short of the four-Ohio total; a 16th finally raises this capacity to 640, a difference of just 3.9%. Under the August 2026 force structure, 19 VPM-equipped Virginia SSGNs each would ultimately provide 760 vertical launch positions, consisting of 532 VPM positions and 228 bow-VPT positions.

The VPM also supplies the launch volume for Conventional Prompt Strike (CPS), but the CPS will not enter service simply because the USS Arizona is delivered. The US Navy uses a cold-gas launch sequence in which compressed gas ejects the missile from its canister before the solid rocket motor ignites at a safe distance from the ship or submarine, unlike the US Army's hot-launch arrangement for the related Long-Range Hypersonic Weapon. The USS Arizona is scheduled for FY2029 delivery, but Virginia-class CPS fielding is planned for the early 2030s and depends on the completion of an underwater test-launch facility expected in FY2030, following an initial naval integration aboard Zumwalt-class destroyers. To date, the Tomahawk therefore remains the established initial VPM missile. The program's estimated life-cycle cost increased from roughly $31 billion for 262 missiles in 2020 planning to roughly $41 billion for 224 missiles in the 2024 estimate, a 30% cost increase accompanied by a reduction of 38 modeled missiles. The USS Arizona can therefore arrive in 2029 with the physical volume for CPS while initially relying on Tomahawk, because the submarine, underwater launcher, missile production line, and operational weapon do not reach maturity on the same date.

The VPM's four tubes are also interchangeable payload volumes, so alternative missions directly consume missile capacity. One VPM tube allocated to another payload reduces maximum Tomahawk capacity from 40 to 33; two reduce it to 26, three to 19, and all four leave only the 12 missiles in the bow VPTs. The same interfaces can support large unmanned underwater vehicles, mission equipment, and future weapons, while Dry Deck Shelter support expands options for submerged special operations deployment. The SLCM-N creates another future requirement: on September 26, 2025, the Navy awarded Northrop Grumman Mission Systems and Pacific Engineering prototype launcher-and-canister agreements totaling $26.24 million for integration with Virginia Payload Tube and submarine systems. The SLCM-N integration on VPM Virginias is planned during the 2030s, although no final per-submarine load has been established. A 40-Tomahawk Virginia is therefore a maximum missile configuration rather than a fixed patrol load, because Tomahawk, CPS, SLCM-N, UUVs, and mission equipment ultimately compete for finite large-diameter payload volume.

On August 3, 2026, the Navy redesignated 19 planned VPM Virginias as SSGNs, with deliveries scheduled from FY2029 through FY2038. The distinction is configuration-specific: Oklahoma (SSN-802), the first Block V submarine, receives Block V changes without VPM and remains an SSN, while Arizona, the second Block V hull, adds VPM and becomes SSGN-803. The remaining variable is delivery rate. Electric Boat received the $22.2 billion Block V contract on December 2, 2019, initially covering nine submarines, eight with VPM, plus an option for another VPM boat; the first Block V delivery was then expected in FY2025. The current sequence instead places the first VPM submarine, Arizona, in FY2029, with the 19 SSGNs entering service through FY2038. This creates a capacity transition in which the Navy loses individual Ohio hulls carrying as many as 154 Tomahawks before enough 40-round Virginias are available to reproduce their aggregate magazine.

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Written by Jérôme Brahy

Jérôme Brahy is a defense analyst and documentalist at Army Recognition. He specializes in naval modernization, aviation, drones, armored vehicles, and artillery, with a focus on strategic developments in the United States, China, Ukraine, Russia, South Korea, Türkiye, and Belgium. His analyses go beyond the facts, providing context, identifying key actors, and explaining why defense news matters on a global scale.