Best Buying Virginias: SSN-As Failed Astute Follow-ons and Too Large

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]

Russian Pacific Fleet Nuclear Subs Get Overhead Anti-Drone Nets

The Times of India reports here and above August 10, 2026: "Russia is reportedly installing large anti-drone nets over nuclear-powered ballistic missile submarines at the Rybachiy naval base in Kamchatka. Satellite imagery shows the defensive measures covering submarine berths, highlighting growing concerns over drone attacks against Moscow’s most strategically important naval assets." ---

South Korea's authoritative Military Watch: Force Index website reported on August 9, 2026 at https://militarywatchmagazine.com/article/world-most-heavily-armed-submarines-antidrone-russia :

[Bolded text below are hyperlinks] The Russian Navy has begun installing extensive anti-drone netting over nuclear-powered ballistic missile submarines at the Rybachiy naval base on the Kamchatka Peninsula, according to newly released commercial satellite imagery. 

[Google AI: Rybachiy is Russia's premier nuclear submarine base for the Pacific Fleet, located inside Avacha Bay on the Krasheninnikov Peninsula, directly adjacent to the closed military town of Vilyuchinsk and across the bay from Petropavlovsk-Kamchatsky.]

The images, obtained from [US geo-spatial company Vantor - though images most probably first detected by the US National Reconnaissance Office] shows multiple Russian submarines at Rybachiy covered by large overhead nets, with protection extending across several submarine berths. The development represents a striking expansion of the defensive measures Russia has introduced in response to the rapid growth of Ukrainian unmanned warfare and demonstrates that concerns over drone attacks now extend to some of the most strategically important assets in the Russian Armed Forces.

The fact that such measures are being installed over ballistic missile submarines is highly significant, as these ships were designed primarily to survive by remaining undetected and operating at sea, rather than by absorbing attacks while sitting in port. Once a submarine is alongside a pier, however, its enormous size and predictable location can make it substantially more vulnerable to increasingly sophisticated unmanned systems. Rybachiy is particularly significant because it serves as the principal Pacific Fleet base for Russia’s Borei class nuclear-powered ballistic missile submarines, which are the most heavily armed warships in the world.

Ukrainian forces have demonstrated an ability to conduct long-range attacks deep inside Russian territory and have increasingly employed unmanned surface vessels and aerial drones against Russian naval infrastructure. The June 2025 Operation Spider’s Web saw Ukrainian forces target Russian strategic bombers thousands of kilometres behind the frontlines by launching drones from deep inside Russia, further demonstrating the potential vulnerability of high-value military systems far from Ukrainian controlled territory. While thus may have influenced the decision to fortify the Rybachiy facility, the fact that U.S., Japanese or other hostile forces in the Pacific could potentially also launch drone attacks in wartime provides a further incentive to do so. 

Footage from across Russia has shown continued operations fortify high value targets against drone strikes, including the deployment of Mi-26 helicopters in Moscow to position - Pantsir-SMD-E stationary air defence systems onto the rooftops of high rise buildings. The growing reach of drone attacks has increasingly threatened targets deeper into central Russia, including its industrial heartlands in the Urals region. Drone and missile attacks launched from Ukraine against strategic targets in Russia have received very considerable support from across the Western world, including funding, training, supplies, and intelligence. A Financial Times report in late July revealed that the United States and France were playing a central role in facilitating Ukraine’s long-range drone strikes against Russian infrastructure, housing and military facilities, including by providing intelligence used to identify targets and avoid Russian air defences. 

Borei class submarine  incorporate cutting edge quieting technologies, and each integrate 16 RSM-56 Bulava submarine-launched intercontinental range ballistic missiles. Each missile integrates multiple independently targetable nuclear warheads, with the design having been developed specifically to overcome modern missile defence systems through high manoeuvrability, decoys and advanced penetration aids. Russian and Western officials have widely alluded to the importance of the Russian nuclear deterrent in deterring attacks by NATO member states, with the head of the NATO Military Committee Admiral Rob Bauer having stated in November 2024 that he was “absolutely sure if the Russians did not have nuclear weapons, we would have been in Ukraine, kicking them out.”

See map position in far east Siberia Russia's Rybachiy Naval Base at x.com image from HERE 
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Excellent Arpit Kanodia History of Indian Nuclear Weapons Political Background

Arpit Kanodia made some interesting comments on August 6, 2026:

"I think that's giving the U.S. far more credit than the historical record supports.

The one major exception was in the 1950s and 1960s under the Atoms for Peace framework, when Canada supplied the CIRUS reactor (with U.S.-supplied heavy water) and later CANDU-derived technology was made available for India's civilian nuclear program. Ironically, the plutonium produced in CIRUS was used for the 1974 Smiling Buddha test. 

But after the 1972 Nixon-Mao rapprochement and India's 1974 nuclear test, Washington's policy shifted dramatically. The U.S. backed the creation of the Nuclear Suppliers Group, tightened export controls, and spent the next three decades trying to restrict India's access to nuclear technology. [Until accepted by President Obama in 2010.]

It's also worth remembering the strategic situation India faced. By the early 1980s, there were credible reports that Pakistan had cold-tested a nuclear device, and by the late 1980s its nuclear weapons program was widely understood to be nearing completion. At the same time, China had already been a nuclear power for two decades. India was facing the prospect of two nuclear-armed adversaries.

PM Rajiv Gandhi is often remembered for the IPKF debacle, but one of the most consequential decisions of his tenure was pushing forward the weaponization effort and preserving India's nuclear option. That laid much of the groundwork for what followed.

The 1990s were an especially difficult period. India was dealing with insurgencies in Kashmir and the Northeast, militancy in Punjab in the preceding years, a severe balance-of-payments crisis, and sustained U.S. pressure under the Clinton administration to cap or roll back its nuclear program and sign the CTBT. Despite all that, Prime Minister P. V. Narasimha Rao kept the program alive while simultaneously liberalising the economy and restoring India's strategic position. Many also credit him with authorising preparations for nuclear testing in 1995, which were reportedly deferred [until 1998] after U.S. satellites detected activity.

It's entirely possible that U.S. intelligence knew a great deal about India's nuclear program [especially through HumInt] that's what intelligence agencies do. But knowing about it is very different from permitting or supporting it. With the exception of the early civilian nuclear cooperation that unintentionally benefited India's program, the historical record after the 1970s is overwhelmingly one of technology denial, sanctions, and diplomatic pressure rather than quiet approval.

As for Pakistan, the case for quiet tolerance is far more plausible - anyone who has studied A.Q. Khan's procurement network can't help but wonder how such an extensive operation was allowed to function for so long during the Cold War. [Pete Comment: A case of US strategy to balance the nuclear weapon capabilities of India, China and Pakistan.]

Why France Build's SSNs only for itself and Only Exports Diesel-Electric & AIP Subs

Partly utilising the wonders of Google AI Pete has created:

Question: Why does France only use SSNs for itself while only making diesel electric submarines for export?

Answer: Based on the sweat of millions of writers (and I don't get paid - just patriotism :) comes:

France uses nuclear-powered attack submarines (SSNs) for its own navy because it requires global reach and continuous strategic deterrence, but it exports diesel-electric submarines because strict non-proliferation laws, high costs, and low buyer demand make nuclear exports impractical. [1, 2, 3, 4]

1 is https://www.nti.org/analysis/articles/france-submarine-capabilities/

Why France Uses SSNs

Global Operations: France has overseas territories and global defense commitments. Nuclear subs can travel fast and far without ever needing to surface.

Carrier Strike Group Support: French SSNs protect the Charles de Gaulle nuclear aircraft carrier, matching its high sustained speeds. It can do at least 27 knots - see right sidebar.

Strategic Doctrine: France treats nuclear propulsion as a vital, sovereign military secret tied directly to national safety. [1, 2, 3, 4]
On top of SSNs France cannot afford diesel-electric+AIP subs for itself. In any case, there are sufficient supportive NATO allies (Germany, Italy now Sweden and eventually Norway and Poland) with AIP for shorter range sea missions - mainly against Russia.

• [Pete comment: Only SSNs can reliably defend France's SSBNs from Russian SSNs and Russian fast surface ships - particularly when French SSBNs are leaving-entering France's SSBN base at Île Longue (Long Island), Brest, Brittany, western French coast.] 

An excellent Indian In Our Defence video (here and above). Interviewee explains the differences between Diesel-Electric+AIP and Nuclear powered submarines. (Accents not too heavy for me - but please also use the "Subtitles/Closed captions" thingy second to the left on the right-lower corner of the video image).

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Why France Only Exports Diesel-Electric + Rarely AIP add-on Submarines

• Non-Proliferation Rules: Exporting naval nuclear reactors risks spreading sensitive technology that can be weaponized. [And France would get blamed as the original reactor source. Hence France claims Brazil is only developing an indigenous Brazilian submarine reactor. A fine line.]
  
  
Market Demand: Most nations only need coastal or regional defence submarines. Diesel-electric boats (like the Scorpène-class) are quieter in shallow water, much cheaper to buy, and cheaper to run. 
Buyer Constraints: Most countries lack the specialized nuclear infrastructure, legal frameworks, and trained personnel required to safely operate and refuel nuclear reactors. [1]

 Pete Comment

After France developed first generation MESMA AIP (with Pakistan the only customer) France has not fully developed second or third generation AIP at sea operationally. Part of this may be development cost, India resenting any more French AIP for Pakistan. competition too high from Sweden’s Stirling and German PEM AIP. Also France’s Scorpene customers (Chile, Malaysia, Brazil and eventually Indonesia) get more benefit from batteries. Whether India’s Kalvari Scorpenes will ever be retrofitted with AIP is an open question.  

About larger French designed subs for the terminated Australian Shortfin/Attack class and the Netherlands' continuing Orka Program - they did not want AIP. This is because their long range/high speed transit mission profiles gained/gain little or nothing from heavy liquid oxygen (LOX) AIP technology after the LOX is used up. 

Unsurprisingly there is no standard power mix solution for submarine exporters' own needs and their customers' needs. It depends on their mission needs, geography, cost and many other factors. 

Novel (non-PWR) Reactors for Submarine Problematic: SK's Molten Salt Reactor Program

Arpit Kanodia at 7/31/2026 6:41 PM made some very interesting comments regarding problematic non-PWR novel reactors:

"Reply to Shawn C [Pete will also reply to Shawn in a future article] from previous post: The marine reactor South Korea (SK) is trying is an MSR (Molten Salt Reactor). [Pete AI confirmation is HERE] I don't know what their goals are or what they are trying to achieve, but not a single land-based commercial reactor based on an MSR exists; they are all test reactors. And the (SKs) want this for marine ships and submarines? This is nothing but hubris." [Pete comment - Very true Arpit] 

[Pete's has used Google AI, yielding ]

 "Neither the US nor the Soviet Union ever used Molten Salt Reactors (MSRs) in operational submarines. However, both nations experimented with liquid-metal cooled reactors during the Cold War, which are sometimes confused with molten salt systems. 

Soviet Liquid-Metal Submarines Project 645 (K-27): The Soviet Navy built one experimental submarine powered by twin lead-bismuth eutectic (liquid metal) cooled VT-1 reactors. It suffered severe reactor problems and a core partial meltdown in 1968.

Alfa Class (Project 705 "Lira"): The Soviets later built a series of high-speed attack submarines powered by lead-bismuth liquid-metal reactors (OK-550 and BM-40A). While fast and deep-diving, their coolant systems had to be kept externally heated at all times in port to prevent the metal alloy from solidifying. [Pete: The Alfas docked in very cold Arctic ports.]

See WaldenFont's comments 6 years ago: 

"Those reactors are something else. The coolant is a molten lead alloy. Once the reactor is running, it has to keep running all the time. If it ever stopped, and the alloy cooled, the entire cooling system seizes up and can’t be started again. Maintenance had to be done in port, with the coolant rerouted through an external furnace to keep it molten."

US Liquid-Metal Submarine [a very early "Seawolf" SSN-575 - nothing to do with the 1990 onwards seawolf class]: The US Navy tested a liquid sodium-cooled reactor on this single-hull attack boat. Sodium proved hazardous and difficult to manage due to its violent reaction with water, so the Navy decommissioned the plant and rebuilt the submarine with a standard PWR." [AI portion ends]

The US Atomic Energy Commission (AEC) historians' [according to Wikipedia] account of the sodium-cooled reactor experience was:

"Although makeshift repairs permitted the Seawolf to complete her initial sea trials on reduced power in February 1957, RICKOVER had already decided to abandon the sodium-cooled reactor. Early in November 1956, he informed the AEC that he would take steps toward replacing the reactor in Seawolf with a water-cooled plant similar to that in the Nautilus. 

The leaks in the Seawolf steam plant were an important factor in the decision but even more persuasive were the inherent limitations in sodium-cooled systems. In Rickover's words they were "expensive to build, complex to operate, susceptible to prolonged shutdown as a result of even minor malfunctions, and difficult and time-consuming to repair."[6]

The S2G reactor was replaced with a pressurized water reactor similar to Nautilus and designated S2Wa, the replacement process lasting from 12 December 1958 to 30 September 1960.[7]"

[Arpit continues] 

"This was the same thing tried by India in the 1980s. In 1980, DRDO proposed a [pressurised HEAVY water reactor] PHWR reactor for submarines, which [Indian] Naval Headquarters refused to sanction, and rightly so, it was madness."

SubMatts will resume with Arpit's very interesting comments on the dangers and complexities (adding up to extreme costs) of refuelling submarine reactors later in August.

Submarine Reactors from Rickover to Gorshkov and Beyond

My responses to parts of the late 2026 comment string include.

Even the US may have been unable to build a submarine reactor without the political connections, budgeting and engineering brilliance of Admiral Rickover. This Wikipedia entry has seemingly intentionally deleted almost all of Rickover's huge contribution to nuclear power - giving "Mamie Eisenhower" equal opportunity billing. Rickover successfully project micro-managed construction, land and at-sea testing of submarine and surface ship reactors and dictated the regulatory environments for them. He did the same for the land based civilian reactor sector and most things radioactive safety.

Britain totally relied on the US for submarine reactor development from 1959. Britain then refused to admit it benefitted from continuing US assistance and inspiration for PWR1. British nationalistic pride, Rolls Royce commercial objectives and US military industrial reluctance may have amounted to insufficient US assistance for PWR2. This partly explains PWR2's technical shortcomings. I admit I talk too often about PWR2 - yet it has largely incapacitated the 10s of $Billions UK Astute class, while also limiting the UK Vanguard class. Whether the UK can garner sufficient US assistance for PWR3 and PWR3+/4 remains an Anglophone anxiety.

Russia had/has a large enough industrial base, inventive talent, Admiral Gorshkov, set of national priorities (eg. nuclear weapon strategy) and skilled espionage to largely parallel develop submarine reactors. 

China, France and India benefitted from similar strengths as Russia.

Arpit is right in questioning whether middle power, South Korea, can develop submarine reactors like the great-sometimes super powers above. China, a superior innovator and manufacturer to SK, has taken decades longer than China hoped to develop quiet, efficient, submarine reactors. 

Also SK suffers from poor geography. However good the nuclear submarines SK builds they are hemmed in by the Japanese island chain and close proximity to NK and more especially to Chinese and Russian fixed undersea sensors, SSNs, SSKs and other nearby ASW platforms. 

SK and China may be strongly opposed to Japanese naval/military resurgence in the shape of Japanese developed nuclear submarines.

It is only the US that has the benign vast ocean space geography to fully benefit from the speed and other characteristics of nuclear submarines. The US advantage includes "owning" the Western Hemisphere for thousands kms until it gets to adversaries - Bering Strait excepted.

There is much more in the late July 2026 comment string that I'll respond to in future weeks.