The Virginia Class submarine is already heavily armed. Each boat can carry up to 37 torpedo-sized weapons, such as Tomahawk cruise missiles. Twelve of these slots are in two vertical launch systems (VLS), known as the Virginia Payload Tubes. The new Block V (5) batch of submarines will add 28 more slots in its VLS. This is an increase of 76% of torpedo-sized weapons.
The U.S. Navy is planning to build between 72 to 78 new attack submarines. Ten of these will be the Virginia Block V boats, 8 of which will be up-armed as described here. Based on a recent briefing document from the Congressional Research Service, reported in US Naval Institute News, a total of 31 Virginia Class submarines will ultimately have this fit.
When it was originally conceived the Virginia Class was seen as a cheaper alternative to the larger Seawolf Class. The Seawolf had been designed during the Cold War to counter the latest Russian submarines. But the Russian types were mostly cancelled (or massively delayed) in the post-Cold War period. Therefore only three of the expensive Seawolfs were eventually built. Yet while the Virginia Class was smaller than the Seawolf, it took advantage of new technologies and itself became a world-leading nuclear powered attack submarine.
The Block II Virginias continued to focus largely on production efficiency. The Block IIIs took this further with enhanced construction techniques. At the same time they received a new conformal main sonar array in place of the traditional spherical array found on earlier U.S. Navy submarines. Their vertical launch system was changed from 12 single tubes to two ‘Multiple All-Up Round Containers’. These are the Virginia Payload Tubes.
The Block IV, which are mostly still under construction, again focused on reducing cost. They also improved availability. But the improvements were iterative and mostly hard to see. Outwardly Block V will be more visibly different, with a new weapons module and additional sensors.
They will be extended with the addition of an 84 foot (25 meters) section to accommodate the four new vertical launch tubes. Each of these will be capable of carrying 7 Tomahawks. The new VLS is termed the Virginia Payload Module and will also be suitable for future weapons and alternative payloads.
The Block V Virginia Class Submarine Will Have New Weapons
The latest Tomahawk missiles, coincidentally also known as the Block V, will add an anti-ship capability to the existing land-attack mode. They are expected to be operational before the first Virginia Block V joins the submarine force.
More potent still, although unconfirmed, are likely to be new hypersonic boost-glide vehicles. It is unclear how many will be carried in each VLS but a reasonable guess is three rounds. Because the Block Vs have more VLS slots it seems natural that they will be among the first submarines to carry the hypersonic missiles. With a total of 6 VLS tubes they could carry a mixed load of, perhaps, 12 hypersonic missiles (3 in each of the aft 4 tubes) and 12 Tomahawks in the forward tubes.
The submarines will still have the regular torpedo room (weapons stowage compartment). This can carry the latest versions of the ADCAP (Advanced Capability) family of heavyweight torpedoes. They are also likely to carry the new Hammerhead mine which will replace the legacy Mk.47 submarine launched mobile mine (SLMM).
Hammerhead will allow covert deployment of bottom mines. Although less glamorous than missiles this is a particularly powerful capability. The U.S. Navy is also developing a new Clandestine Delivered Mine which will blend technologies from underwater drones with regular bottom mines. This will allow much greater stand-off ranges when sowing mine fields, thus improving both survivability and operational flexibility.
On the sonar front the Block Vs are expected to receive the Large Vertical Array (LVA) flank sonars. These are in addition to the six ultra-modern Light Weight Wide Aperture Arrays (LWWAA) which are placed along the submarine’s side. There are indications that a LVA has recently been fitted to an Ohio Class ballistic missile submarine, the USS Tennessee (SSBN-734).
Taken together the improvements will make the Block V the most heavily armed attack submarine in US Navy history. Whether they will in future receive the classic ‘SSGN’ designation, like the four converted Ohio Class cruise missile submarines currently in service, remains to be seen. Even if not their impressive cruise missile load will differentiate them from other attack submarines. Even their big brother, the larger Seawolf Class.