Best Buying Virginias: Astute a Failed Program Meaning SSN-A Followon High Risk

In response to points raised by Arpit Kanodia on August 9, 2026.

In Australia's case there's no way we could build SSNs - especially the reactor half - under a plan relying on the UK's failing submarine industry - to oversee construction of SSN-AUKUS aka "SSN-A"(which will be an overly large advanced Astute) at Osborne, South Australia.

Buying 8 Virginias (already useful for close to shore work) and of proven working design is our best bet. They will likely only be available to the RAN after 2040, while Columbia SSBN construction delays full production of Virginias. Delays may mean the final 3 Virginias Australia buys are Virginia Block Vs and Block VIs. Both Blocks will feature flexible missile choice Virginia Payload Modules (VPMs). VPMs can host Tomahawk SLCMs but will also be able to host Submarine Launched Hypersonic Missiles (SLHMs.)

Australia needs to further upgrade Fleet Grade West basing (costing many $Billions) for a US SSN squadron. UK SSN's are only available once a year on propaganda visits,

This is noting Fremantle, Western Australia was a massive US, UK and Dutch submarine base in World War Two secretly hosting several squadrons in the war against Japan. 

We also need to continue upgrading of SSN repair facilities at Osborne. The Osborne facilities could help ease the burden of the over-extended US SSN repair effort.

Fortunately US Democrats and also Republicans indicate they support "proliferation" to the RAN of some Virginias - with the latest proven US reactor design. 

Australia would do best to have an all SSN submarine service. Our Collins SSKs can only be extended to about 2044 - though useful in northward straits and narrows. Any new class of RAN SSKs would take 25 years for Australia to build. Buying foreign built SSKs doesn't seem to be politically possible in Australia. A parallel new SSK program would overstretch our huge submarine budget (orientated to AUKUS and the Collins LOTE).

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Compared to currently operational US Virginias a major failing of the SSN-A is it  being a follow-on to the failed Astute and size to accommodate the larger PWR3 reactor called PWR3+ for SSN. There is mighty shallow water Australian subs need to operate in to our north.

Google AI advised on August 11, 2026:

The UK’s Rolls-Royce PWR3 [and PWR3+] reactor[s are] larger and more powerful than the older PWR2 design. [1, 2]

Size and Design Comparison

PWR2: Powered the Vanguard-class and Astute-class submarines, requiring a substantial hull diameter but utilizing an older core configuration that required mid-life refuelling or core updates. [1, 2, 3]
PWR3: Developed for the much larger Dreadnought-class ballistic missile submarines and selected for the future SSN-AUKUS attack submarines (using a variant called PWR3+). It has a physical footprint and core design necessitating a wider hull diameter (12.8 meters on Dreadnought) compared to preceding boat designs. [1, 2, 3, 4]