AUKUS Failing TWO - UK cannot afford a revolutionary SSN-AUKUS project

It looks like the UK cannot afford AUKUS Pillar 1 given its new NATO and new Ukraine obligations:

The UK no longer has the money to develop the SSN-AUKUS intended for Australia and, in particular will have difficulty rectifying the PWR2/PWR3 submarine reactor problems in time.

Only by the late 2040s can the UK (in a worse state than the US) develop and deliver SSN-AUKUSes. Given the increasing commitments for the UK defence budget SSN-AUKUSes may be only be evolved Astutes with evolved PWR2s renamed "PWR3". 

After several evolved UK SSN classes since 1966 (ie. the Valiant - Churchill and Swiftsure classes) that ended with the Trafalgar class all using the PWR1 the Astute class. since 2010, is a "revolutionary" advance. The Astutes have a fundamentally different, much larger hull with a larger and it turns out troubled PWR2 reactor - piping arrangement. It is not possible for a cash strapped UK to undertake yet another revolutionary advance in the shape of a wholly new SSN-AUKUS. Rather, SSN-AUKUSes are much more likely to be evolved Astutes.

UK Defence Secretary Healey’s embarrassing (to Australian Defence Minister Marles, the RAN and Australian PM Albanese) June 11, 2026 resignation over UK defence money worries indicates the UK simply does not have the Defence Budget to face all of the UK’s worsening NATO/anti-Putin priorities. The UK now uses the slogan "NATO First" for a new priority - UK RAF nuclear strike - which does not include submarines for Australia. UK Armed Forces Parliamentary Under-Secretary of State Al Carns, also resigned over budgetary shortfalls. 

The UK's defence budget problems that are negatively impacting the UK's SSN-AUKUS project are impacted by Trump's long term distrust over NATO. Trump is believed to rely on "what to do with NATO" advice from Putin. Putin telling a gullible Trump that NATO is a separate entity from the US that exploits US financial goodwill. 

Trump’s withdrawal from many NATO and Ukraine responsibilities mean non-US NATO countries, including the UK, have to spread their forces and budgets thinner. Following the US withdrawing funding support for Ukraine major NATO counties like the UK are paying for Ukraine instead, The UK defence budget is also thinning to cover new UK funding for East European NATO members threatened by a warlike Russia. 

REACTORS

The need for Australia to have already paid A$5 Billion (so far) to UK Rolls Royce for the PWR3 indicates a severe UK money shortage for AUKUS. The PWR3 is being designed to power the UK's Dreadnought-class SSBNs and the Astute successors, the SSN-AUKUSes. 

The UK is also exhibiting a technical inability to maintain the PWR3's precursor, the PWR2 - used on the Vanguard SSBNs and on the Astute SSNs - see all UK SSNs are at present again unavailable, due to repeated piping to PWR2 reactor faults.

Please scroll half way down this Turner, Julian (29 July 2013) article here at https://www.naval-technology.com/features/feature-nuclear-submarine-successor-uk-royal-navy/?cf-view to subheading “Power surge: PWR-3 propulsion, munitions and electrical systems” indicating that in the years up to 2013 there was US assistance for then UK Successor-class/now renamed Dreadnought-class SSBN's PWR3/PWR-3. Also see https://en.wikipedia.org/wiki/Rolls-Royce_PWR#PWR3  "PWR3 was a new system "based on a US design but using UK reactor technology".^[22][23] 

PWR3 submarine reactor development is also intended for SSN-AUKUS.

The UK may be receiving less US technical/monetary support for PWR3 reactor development because Trump and Hegseth now see the PWR3 as an undeserving  NATO project.

Unless Australia funds (say) 80% of SSN-AUKUS and PWR3 costs the UK, at best,  may only be able to provide Astute/PRW2 variants to go into “SSN-AUKUS” in the late 2040s/early 2050s.

Australia gets what the US and UK deign to give us, after the needs of the America First USN and then the NATO First UK are met.

AUKUS Failing ONE: US Virginias unavailable

It looks like both of Australia's AUKUS Pillar 1 allies US and UK (see next article AUKUS Failing TWO) will not meet their obligations because:

The US lacks the shipyard labour and supply chain efficiency to build Virginia SSNs and higher priority Columbia class SSBNs quickly enough; has a very inefficient Virginia-class maintenance process meaning too many Virginias are unavailable awaiting maintenance/repairs; and lacks the political inclination to put its Australian ally's needs for Virginias over US Navy needs.

and

It is likely Australian Defence Minister Richard Marles’ May 31, 2026 acceptance of three aging Block II or III Virginias (rather than two old and one new Virginia) was a delayed response to hitherto secret US War Department Elbridge Colby’s 2025 Review results. In 2025 Marles and Colby parroted the confected AUKUS is “full steam ahead” slogan. Colby has been long opposed to the US delivering ANY Virginias to Australia. 

In the meantime the US was only too happy to receive a A$5+ Billion AUKUS deposit from Marles.

Non-delivery of Virginias has always been on the cards until the US builds 2.33 to 3 every year. The US cannot achieve such numbers until the US has completed its higher priority run of 12 already delayed Columbia SSBNs, one per year 2031 – 2043. Then the US may be in a position to deliver to Australia one Virginia every 3 years from 2044, 2047 and 2050.

It is odd the Australian Submarine Authority (ASA) without providing any hard evidence, has been spinning that used Virginias are better than new ones. Is ASA arguing it is preferable Australia receive:

-  at worst in 2044 a mid-life updated 31 year old, commissioned 2013, Block II Virginia (like USS Minnesota), 

or 

-  at best a 24 year old Block III Virginia, commissioned in 2020 (like USS Delaware)

-  and Marles/ASA have been spinning the falsehood that old Virginias would be  better than new build commissioned in 2044 Block VI Virginia (like USS Brooklyn).

Also where in the troubled heavy (non-reactor) overhaul queue will aging Australian Virginias be placed versus the USN’s own Virginias? The 4 USN shipyards doing heavy overhaul have long queues and many problems like a shortage of skilled workers and supply chain problems. Can we expect ASC Osborne or Australian Fleet Base West to more efficiently handle heavy maintenance of old Aussie Virginias?

Remember we are also talking America First’s Trump and perhaps next from 2029 to 2032 a President J D Vance - both not known for worrying about alliance loyalties (except with Israel) or for keeping promises. There is no contract prescribing Australia will get Block IVs – only ASA-Marles spin which has been lapped up by some thinktank, mainstream media and academic cheerleaders.

IF we get a Virginia in 2032, who’s to say it won’t be Block II or at best a III and its just going into, or within, a deep maintenance cycle? We’ve already paid/been paying A$5 Billion deposits (maybe more by 2032 – there being no contract that we only have to pay A$5 Billion).

By 2032 the deposits we’ve sent to the US may be all that aging 20-30 year old Block IIs or IIIs are worth.

I think, through thought repetition, we’ve convinced ourselves our A$Billions are “gifts” but where’s the proof? Things may be worse, with the US and UK seeing these as deposits, that bind Australia to pay much, much more over the next 30+ years.

How can we be certain of anything when AUKUS Pillar One is commercial and national security in Confidence? And AUKUS may involves changeable deals – spread over several US presidencies, every 4 to 8 years, and twice+ as many UK PMships. The Brits are changing their PMs and Defence Secretaries very frequently.

I don’t see any Australians as the authorities on AUKUS. We get what the US and UK deign to give us, after the needs of the USN and then the UK RN are met.

Navigating the Deep: An Analysis of the Canadian Patrol Submarine Project (CPSP)

I draw your attention to a great June 9, 2026 essay, written by Bruce Allen Lubbering, for RealClear Defense, at:

https://www.realcleardefense.com/articles/2026/06/09/navigating_the_deep_an_analysis_of_the_canadian_patrol_submarine_project_cpsp_1187505.html 

Please direct any comments there.

No UK Astutes Available Again! Safety Fears Demand Lengthy Repairs

Article

Please read https://www.yahoo.com/news/world/articles/navy-entire-fleet-submarines-while-131000399.html of June 7, 2026, first.

Pete Comments

The UK Royal Navy (RN) is again suffering, politicly embarrassing, defensively dangerous, nuclear attack submarine (SSN) unavailability. This means all five Astute-class SSN's (HMS Astute, Ambush, Artful, Audacious and Anson) are unavailable, awaiting maintenance and repairs. The sixth (HMS Agamemnon) commissioned September 2025, is not yet ready to deploy. Last of class, HMS Achilles, is due to be commissioned sometime in 2028-29. 

Constant checking by the RN detects a fault familiar to the RN. That is weakened or frayed piping that works with each Astute's PWR2 Reactor. Hot Pressurised water/steam can stress the piping over time. Minute piping holes may cause a release of low level radioactive water. If left undetected or unrepaired this may cause the piping to burst. 

While the piping contains hot water/steam this is not as hot as the fissioning U235 in the core of the reactor. However slowdowns or interruptions to the water/steam may cause an increase in temperature within the reactor which causes or triggers an automatic emergency shutdown of reactor function (called a reactor "trip" or "Scram"). 

So it is important that piping is intact and working efficiently. For the Astute's PWR2 reactor this is essential. 

Put another way once the pipes split there can be loss of water based coolant demanding shutdown of the sub's reactor (at sea and especially in port). Any risk of release of coolant to civilian populated areas is, according to the UK Ministry of Defence (MoD), negligible, nothing to worry about. Although the dangers of this piping-to-reactor-risk has been examined and debated for many years. See this semi-paywalled 2011 Guardian article https://www.theguardian.com/world/2011/mar/10/royal-navy-nuclear-submarine-reactor-flaws . Failing that see this 2014 BBC article https://www.bbc.com/news/uk-politics-26463923 ). 

This problem was earlier observed with the UK's post-collision HMS Vanguard  nuclear missile submarine (SSBN). 

Above is the US Los Angeles-class nuclear submarine, USS San Francisco, in drydock following its collision with the seafloor northeast of Australia in 2005. 98 (most) crewmen were injured, one died. Her reactor was not damaged.

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Nuclear sub owning governments routinely assure publics how safe nuclear sub operations are. Here is the very long list of submarine mishaps, including an explosion and nuclear submarine collisions, since the year 2000.

During the Astute-classes availability failure the RN must rely on USN or French Navy SSNs to perform the highest priority tasks of escorting UK Vanguard-class SSBNs in and out of the UK SSBN base. The base is HMNB Clyde, near Glasgow, Scotland.

The mainly UK designed submarines, known as SSN-AUKUS, that Australia will buy/build, later than we're paying for, around 2045, will be heavily based on the Astutes. The PWR3+ reactor powering SSN-AUKUSes will owe much to the troubled PWR2 design. 

Updates on India's Upcoming K-5 SLBM

On 12 September 2025, India’s DRDO had carried out a static test-firing of the second-stage solid rocket motor of the K-5 Submarine-Launched Ballistic Missile (SLBM) at the Advanced Centre for Energetic Materials (ACEM), close to the City of Nashik, in central-western India. This information was revealed in the November 2025 issue of the DRDO’s Newsletter publication (a publicly-available document). The publication provides many interesting details about the K5-S2 (Project K5-Stage 2) motor, but the most interesting is obviously the diameter of this second-stage motor: 2.4 meters!

Official publication from the DRDO Newsletter (November 2025 issue, linked above) detailing the second-stage solid rocket motor of the K-5 SLBM
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This figure (which can be extrapolated as applying to the whole missile, not just the second stage) would make the K-5’s diameter comparable to the Soviet/Russian R-39 Rif, and bigger than the diameter of most contemporary intercontinental-range SLBMs like the American UGM-133 Trident 2-D5 (2.11m), Russia’s new RSM-56 Bulava (2.0m) which directly replaced the R-39 Rif, Chinese JL-2/3 (2.0m) and even the French M51 (2.3m). The K-5 also reportedly carries forward the K-4's overall vertical length of 12.0m, which is comparable or shorter than most of the contemporary SLBMs mentioned above.

It was originally believed that the K-5 might find application on the Arihant-class SSBNs (inclusive of the larger Arihant Stretch sub-class) as a longer-ranged replacement for their currently-carried K-4s. It was also believed that the K-6 (another next-generation SLBM also in development) might be exclusively for use onboard the upcoming S-5 class of SSBNs, the first two boats of which are reportedly in construction, as covered in my previous article. But now it appears both the K-5 and K-6 would be exclusively deployed only on the future S-5 class SSBNs, as it should be impossible for the vertical missile tubes on the Arihant/Arihant Stretch-class boats (designed to carry either a single K-4 SLBM of 1.3m diameter or up to 3 x smaller K-15 SLBMs of 0.74m diameter each) to carry these larger missiles. This is because the K-5 evidently represents nearly a DOUBLING of the missile body’s diameter over the K-4.

As I speculated earlier, the lack of a prominent ‘missile hump’ on what is assumed to be a newer iteration of the S-5 SSBN’s hydrodynamic model, as opposed to the earlier one which had a very pronounced hump, might have been an indication that the intended missile armament of these boats may have undergone a significant change in configuration over a period of time in the late 2010s or early 2020s. This change in configuration may have been a result of the DRDO’s efforts to develop SLBMs that are shorter in length, at the cost of being larger in diameter, while still being able to reach the same range with the same payload capacity as before.

Typically, increasing the length of the missile in order to increase the amount of solid fuel propellent it can carry is relatively easy & straightforward. But increasing the diameter to achieve that same goal (carrying more propellent) while maintaining the same or shorter vertical length is much more challenging, as it would involve the forging of larger & larger steel and/or carbon-composite casings, a complicated industrial process that requires the commissioning of new infrastructure. Additionally, it would also require significant advancement in chemical composition of the solid-fuel propellent itself.

A conceptual, indicative illustration of what was described as a 'future SLBM', shared by then-Chairman of the DRDO, Dr. V.K. Saraswat during a presentation to the engineering students of IIT-Bombay university in 2014. Sourced via Bharat Rakshak Forum.
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Is the emergence of what is believed to be the newer iteration of the S-5 SSBN, with a thoroughly 'streamlined' missile hump, an indication that DRDO has made sufficient advances in this field of missile propulsion & construction? Until we see the first real images of an actual S-5 hull, we can only speculate.

In other news, veteran journalist Sandeep Unnithan, who I often quote as a very reliable source in the field of India’s nuclear submarines & adjacent programs, has reported that a ‘pop-up’ test of the K-5 SLBM was conducted from a submersible pontoon in March 2026. A pop-up test is basically an exercise to certify the gas-ejection mechanism that would initially launch the SLBM from the submarine's missile tube to a safe distance underwater before the first-stage solid motor is ignited.

While the pop-up test of the gas ejector seen alongside static test-firings of the solid rocket stages is an indication of the brisk pace of development in the K-5 SLBM program, I would estimate that the first, full-fledged test launch of this next-generation SLBM (or at least the first publicized test) could occur at some point in 2027 or later. That first launch would have to be followed by a multi-year testing program that would involve multiple follow-up launches, all of which are likely to see the involvement of the Indian Navy's Missile Range Instrumentation Ships (MRIS) like the INS Dhruv (pictured below), in order to obtain accurate information regarding downrange telemetry & splash-down patterns of the MIRVed warheads. In tests that cover the full range-envelope of these SLBMs, missile Range Safety Officers (RSOs) deployed onboard such MRIS vessels would hold the decision-making power & communications capability to destroy missiles being tested in-flight, in the event those missiles were to wander significantly off course.

The 15,000-ton MRIS vessel INS Dhruv, equipped with multiple X-band & S-band AESA radars alongside other telemetry-tracking equipment. Photographed by a civilian, sourced via Twitter/X.
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While most quotable reportage of the K-5 SLBM gives it a 5,000-km range while carrying a sizeable 2-ton MIRVed nuclear payload, it remains to be seen whether that range figure is definitive or, as in the case of the land-based Agni-5, deliberately understated as being less than 5,500 kms (thereby escaping the definition of an ICBM) for political reasons. When all is said and done, this could add a layer of ambiguity regarding the reach of India’s definitive sea-based nuclear second-strike capability.

End of article.

No new Virginia(s) for Australia under AUKUS

PETE COMMENT

Long suspected by myself and other independent defence commentators - cracks are becoming severe in US promises of Virginias for Australia under AUKUS. 

And then there are the tame AUKUS boosters - who are ultimately paid by the US and/or the Australian Government...

Just announced by Australian Defence Minister Marles (notably not in the Australian Parliament but under the PR protection of loose understandings in Singapore) is that there will be no new Virginias for Australia under AUKUS, 

This announcement may amount to delayed recognition of the, to date, Secret findings, of the US Department of War's Elbridge Colby AUKUS Virginias 2025 Review. In late 2025-early 2026 the Australian public were assured by the US and a grateful Australia/Marles that new AUKUS Virginias were bundled into a "full steam ahead" prospect. Clearly Marles refused, until now, to reveal that the US had reneged (refused to meet its 2021 promise) on delivering new Virginias. 

So the original September 15, 2021 hopes were that the US would deliver to Australia a used Virginia in (say) 2032, Then, the next two were more vague - maybe a used Virginia in 2035 and a new Virginia in 2038. But all three in the 2040s may be more realistic.

Everything is vague - just the way Trump likes it. The whole world knows Trump doesn't keep his promises and frequently changes his mind. Australia needs an energetic corps of investigative reporters and effective intelligence agencies to anticipate what Virginias (USS so-and-so) the US will be delivering and when. Unfortunately most of the Australian media, thinktanks and academics are trusting, pro-US, pro-Australian Government cheerleaders who can't get their heads around realpolitik.

Today it has been announced that the third, (in say) 2038 Virginia will not be new, but used. Lets now call the Virginias V1Used, V2Used and V3Used.

The vague, vacuous, 2021 AUKUS promise also mentioned the possibility of two further new Virginias - perhaps in the 2040s. Lets call them V4New and V5New. But Marles does not mention any V4New or V5New. So it is possible the US has also reneged on V4 and V5 old OR new. 

It is highly unlikely Australia will receive recently built Block VI Virginias. They are too valuable to the USN. That Australia will receive three used Block VI Virginias is an unsupported rumour spread by the Australian Government and by cheerleaders ultimately paid by the Australian Government. There is no known contract concerning what Virginias (if any) the US Government will deliver or in what years (if any).

The Virginias (if any) Australia receives in the 2030s are likely to be Block Ils, commissioned in 2013 or earlier, already used for 20+ years, in need of costly maintenance, while being restricted to 12 vertical tubes tailored for subsonic Tomahawk missiles only. Instead, maybe Australia will get three used Block IIIs (each with 36 Tomahawks) in the 2040s. An adversary, like China, with its dense anti-missile defences on land and ships, might easily shoot down slow moving Tomahawks, by the time Australia is armed with them in the 2030s or 2040s.

The US has found repair and maintenance of used Virginia's to be a lengthy, expensive and problematic process. So the prospect of V1Used, V2Used and V3Used holds high risks for Australia.

By 2031 the US President of the day may announce Australia will not get V1Used, V2Used or V3Used, as the US Navy (already suffering a severe SSN shortage) needs all Virginias, for US defence, it can get. 

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MARLES' ANNOUNCEMENT IN PRESS ARTICLE BELOW

Stephen Dziedzic in Singapore for Australia's Government owned ABC News, on May 31, 2026 reported at https://www.abc.net.au/news/2026-05-31/australia-to-buy-second-hand-united-states-submarines-aukus/106742496 :

"Australia to buy three second-hand United States submarines under AUKUS shake-up

By foreign affairs reporter Stephen Dziedzic in Singapore

Topic:

• Defence Industry

1 hours ago

Australia will now buy second-hand Virginia-class submarines. (Reuters: Brian Snyder)

In short:

Richard Marles says Australia will purchase second-hand Virginia-class submarines from the United States as part of an AUKUS shift.

Australia was expected to receive at least two used and one new Virginia-class submarine, but those plans have changed.

Mr Marles says there will be "significant" savings for Australia, although it will not make a huge difference to the overall cost of the program.

Link copied

Defence Minister Richard Marles says Australia will make "significant" savings under an AUKUS shift that will see the government purchase only second-hand Virginia-class submarines from the United States.

Under the 2021 AUKUS deal, Australia was expected to receive at least two used and one new Virginia-class submarine.

AUKUS partners unveil plan to develop underwater drones

The US, Australia and United Kingdom have unveiled a new "signature" project to develop cutting edge weapons systems and sensors for underwater drones.

But late yesterday, the US, UK and Australia announced that they would "streamline" the purchase, with Australia no longer buying any new submarines, and acquiring three second-hand submarines from the same production block.

Mr Marles told reporters at the IISS Shangri-La Dialogue in Singapore that AUKUS was an "incredibly complicated" endeavour and "we need to place a premium on simplicity".

"We had the prospect … of almost having four classes of submarines operating at the same time — the last of the Collins Class, two in-service Virginias, a brand new Virginia, and a brand new SSN-AUKUS — that gets pretty complicated," he said.

"What we will have here is a simpler pathway. The Virginias we are acquiring will all be of the same type and I can't overstate the significance of that.

"Chasing simplicity is at the heart of why we've pursued this."

He also said there will be "significant" savings for Australia, although it will not make a huge difference to the overall cost of the ambitious and expensive program.

"It doesn't fundamentally change the equation, but it will help," he said.

Richard Marles says this shift will save Australia money. (Reuters: Edgar Su)

Shadow Defence Minister James Paterson said the shift "warrants a proper explanation from government — more than just a single sentence in a joint statement".

"I will be seeking an explanation from Defence at Senate estimates this week about why this change was made and what the implications are," he said.

The joint US-UK-Australia statement described the change as a mutual streamlining "simplifying supply-chain management, operational and maintenance requirements, and maximising cost efficiencies".

Dr Malcolm Davis from the Australian Strategic Policy Institute (ASPI) said Mr Marles was "correct" that getting three submarines of the same type would have advantages, but there was still no guarantee that the US would agree to sell them to Australia, with its shipyards struggling to lift production rates.

"The Americans still have to have sufficient numbers of boats in order to sell them to us," he said.

Dr Davis said the third second-hand Virginia-class submarine would also have a shorter shelf-life than a new one, although he said this would not necessarily have a major impact.

"We were going to face the same problem in the end … and we'll still get an awful lot of use from these Virginias," he said.

Defence Minister says second-hand subs will save money

Another analyst, Dr Euan Graham, who specialises in Indo-Pacific defence and security, said Mr Marles' argument for simplicity made sense, but it was worth taking it with a "grain of salt" because Australia's hand had likely been forced.

"The glass half empty version is that we are dealing with a curtailment of Australia's ambitions for Virginia-class submarines because this is all the Americans are willing to give us," he said.

"But the glass half full [version] is: this is still going ahead, despite the hand-wringing over the AUKUS review."

Dr Davis said the government also needed to clarify whether the US was open to selling Australia up to five Virginia-class submarines — as was originally flagged — or whether a ceiling had now been set on three.

"If it's the latter then we'll have to make do with three second-hand boats," he said.

"And if SSN AUKUS is delayed then we'll be facing a gap."

The announcement was made on the sidelines of the IISS Shangri La Dialogue. (Reuters: Edgar Su) [Above are all good buddies, smiling for the camera. Australian taxpayers are the ones paying!]

But military analyst Michael Shoebridge said the US Navy was simply reserving itself the "newest and most capable submarines" for itself.

"These second-hand Virginia-class submarines are less capable than the new ones," he said.

"Plus a new submarine is easier to maintain than an old submarine — just like a new car is easier to maintain than an old car."

Mr Shoebridge said Mr Marles' argument around simplicity when it came to maintaining the submarines was "nonsense" because Australia was already meant to be able to maintain every type of Virgina-class submarine at HMAS Stirling in Perth.

"If we're maintaining all the different Virginia-class variants that the US rotates through Stirling, then how does it make a difference what flag is on the boat?" he asked."