Shawn Chung’s November 14, 2023 comment and noting https://en.wikipedia.org/wiki/Virginia-class_submarine#Boats_in_class has prompted me to add the following thoughts:
The
USN has announced the US intends to sell/deliver two used Block IV Virginias to
Australia in 2032 and 2035 see https://www.defensenews.com/naval/2023/11/13/heres-when-the-us-navy-plans-to-sell-subs-to-australia-under-aukus/
A downstream problem, which I don't think is being adequately addressed or at least publicized by the US, is that Australia will be receiving the last or near last two "pure SSN" Block IV submarines in 2032 and 2035 at a time the US is building "SSN compromised" Block V SSGNs.
So, as well as the US's AUKUS obligations impinging on actual numbers of Virginias available to the USN, there will be capability downsides in the mix of specific Virginia Blocks available to the USN.
I say "comprised" because the Block V's Virginia Payload Module (VPM) (see right sidebar of https://en.wikipedia.org/wiki/Virginia-class_submarine) is likely to involve negative trade-offs:
- a Block V will be 25m longer than a Block I-IV, and
- a Block V will be 2,300 tonnes heavier (higher displacement) than a Block I-IV).
This may negatively impact a Block V’s:
- speed (which may be 1 or 2 knots slower than a Block I-IV) and
- maneuverability (eg. a Block V can't accelerate or decelerate as quickly or turn as sharply as a Block I-IV)
In short the USN, until it begins to commission a return to "pure SSN" Virginia Block VIs and VIIs, towards the late 2030s, may have too many "SSN compromised" Block V SSGNs in its Virginia mix in the late 2020s to mid 2030s.
Peter Coates