Replacement of Australia's Collins Class Submarines

Once again, another opinion piece that falls wide of the mark.
Maybe post Dreadnought BAE Systems will have no work, but that's well into the late 2030s or early 2040s before that happens.
 
Maybe post Dreadnought BAE Systems will have no work, but that's well into the late 2030s or early 2040s before that happens.
Hopefully working on Barham and Bellerophon by then...
Hopefully an Astute successor (wouldn't want to guess at name, conventions are up for grabs these days).
 
Indeed. By then though, my rise to power will be complete. "B, Admiral. B comes after A!"
Technically as the next class in line the Dreadnoughts should have been 'B' so Astute successor would have been 'C'.
(actually technically Astute should have been W but I can see why they skipped the rest of the alphabet...)
Anyhow enough of this designation OCD - tuning back now to your favourite Aussie sub soap drama (crikey cobbers it might run longer than Neighbours!)
 
Fairly unlikely. I thought the idea was to buy the successor class of whichever side of the pond wins the study. Is anything changing or is this just folk here postulating?
 
Fairly unlikely. I thought the idea was to buy the successor class of whichever side of the pond wins the study. Is anything changing or is this just folk here postulating?
I suspect the latter rather than the former....
 
My understanding was the Australians had indicated they were looking to buy an established proven design - i.e. Virginia’s or Astute’s as soon as realistically possible, rather than successor designs (given that the later would push the realistic in service dates for Australian SSNs even later and deepen capacity-gap concerns with current Collins subs ageing-out).

Now that apparently intended plan has it’s own potential issues (as discussed in great detail in this thread) and it’s not to say an alternative approach of, say, proceeding with a conventional stop-gap of some kind (even the cancelled French subs but maybe reduced numbers, or something equivalent) but also agreeing to get into the nuclear sub business as a foreign partner, say, in the US next generation attack sub as a longer term project as part of AUKUS, wouldn’t have some arguments for it.
But the later “alternative approach”doesn’t appear to be the plan the Australians are currently pursuing.
 
IMHO, basing US/UK subs in Oz while training and placing crew members from the RAN would enable training and facilities to come on stream in a controlled manner rather than everything being done flat out and making mistakes. It will take quite some time to bring crews up to standard. if rushed, where would crews come from? Stripped from the surface fleet?
Buying current designs will reduce the relevance of what is supposed to be a fleet with long term relevance, wasted money in other words.
 
Well the Virgina’s are intended to still be in production into the 2040’s and US service into the 2070’s (with continuing US support and ongoing updating) so that’s not really a concern for them. And the expectation is that the next class of US attack sub (that will overlap in production with the Virgina’s) will be even larger than the Virgina class so may be even more of (unrealistic?) ramp up in size and crew required than Australia already facing.
And while proposals for early loans or early diverting of US ordered Virgina to the Australian navy appear to be long shots there may be scope for Australian basing of US Virgina’s (or at least frequent visits).

The same can’t really be said of the Astutes with greater risk of support issues given the much smaller UK Astute fleet and that it’s intended production run and service life re: the UK will end rather sooner. And given the small size of the UK Astute fleet and the pressing demands closer to home likely that any UK Astute visits Australia will be rather more infrequent and briefer than their US equivalents.

And even putting these aspects aside given many different factors and precedents it appears highly likely that Australian will end up favouring the US (Virgina) solution rather than a UK (Astute) one.

As discussed previously in this thread it is certain that Australian service people will serve on US and UK nuclear subs as part of the build up to fielding their own equivalent capability.
 
Thanks, I thought the Virginia's wopuld be shorter lived than that. I must have crossed wires somewhere.
 
Thanks, I thought the Virginia's wopuld be shorter lived than that. I must have crossed wires somewhere.
The VPM Virginias have more improvements than just the payload module--- they incorporate normal improvements in equipment etc that keep the design up-to-date - as will future blocks.

Therefore, they will remain relevant long past when the first decommission.

SSN-774 Virginia commissioned in 2004... of the 66 planned, 21 are complete, and 6 are building (with equipment for 6 more in-work).
 
US seems to want increased submarine build and maintenance capacity. Australian boats would assist in this - more craftsmen, more facilities, more subcontractor capacity.
This capability is being added for Columbia, and Australian Virginia boats would decrease risk of this capital investment.
It seems likely that Virginia blocks will be in production until Columbia production matures.

Adding a boat every five years to Virginia production, while Columbus production spins up, would be difficult but not impossible. Mature Virginia production is the best value Australia could expect. It is a unique opportunity to negotiate price, training of Australian yard workers, supervision and support of maintenance facilities, long term maintenance contracts, decommissioning risk elimination, etc...
 
So, the naval reactors would have to be sealed by the US or UK inside the submarine hulls before they came to Australia, remain sealed throughout the 30-year life of the submarine and be removed by the US or UK at the end of that life. That means if the submarines are to be built here, a section of the hull and reactor would need to be built in the US or UK and then moved to Australia. Or, if that is not feasible, then a reactor could possibly be imported into Australia, but with no Australian personnel having access to it at any time, something which would presumably need to be verified by the IAEA in some way that would also not give inspectors access to the reactor.

Can't see that working very well.
 
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Considering that the only reason Poland hasn't yet marched into Ukraine to do some Russian smashing is that Putin has been waving the nuke card like crazy I think the nuclear proliferation treaty has bigger problems than these future boats.
Because clearly the only way to stop nuclear madmen having their way with you is by having nukes of your own.

IOW, the treaty might very well be deader than a Dodo.
 
Because clearly the only way to stop nuclear madmen having their way with you is by having nukes of your own.
Indeed but the problem is if you don't have nukes, would a nuclear madman permit you getting them? You could call it the Putin Paradox i.e. your act to prevent getting nuked, getting nukes, gets you nuked.

On topic: Oh and submarines!
 
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The purpose of the treaty has been since it's inception to stop nations joining the nuclear club. It has provisions for disarmament but they have never been enacted by anybody. Australia decided to sign the Proliferation Treaty when the then Prime Minister, William McMahon deposed John Gorton, his predecessor and decided it would be cheaper than the planned acquisition of nuclear weapons, way back in 1968. We were about 18 months from building our own bomb back then.
 
Because clearly the only way to stop nuclear madmen having their way with you is by having nukes of your own.
Indeed but the problem is if you don't have nukes, would a nuclear madman permit you getting them? You could call it the Putin Paradox i.e. your act to prevent getting nuked, getting nukes, gets you nuked.

On topic: Oh and submarines!
The madman would have to be VERY mad to start a nuclear exchange over that. Because it will invite nukes from unrelated countries. After all, YOU were the nutter to use nukes.
That's the whole problem. Nukes work as a deterrrent, but only as long as you don't use them.

It's the same problem with Russia and their strategy of limited tacnuke use in case of war: It doesn't work. The US wargamed it a LOT, and they allways ended up with full scale thermonuclear war.
 
Reminder folks this thread is about Australia's plans for Collins Class SSK replacements which currently plans to be a SSN of some form. It is NOT about nuclear weapons!
 
IMHO, basing US/UK subs in Oz while training and placing crew members from the RAN would enable training and facilities to come on stream in a controlled manner rather than everything being done flat out and making mistakes. It will take quite some time to bring crews up to standard. if rushed, where would crews come from? Stripped from the surface fleet?

I concur. Would it not make sense to begin training for the new boats with net-new recruits?

Buying current designs will reduce the relevance of what is supposed to be a fleet with long term relevance, wasted money in other words.

Well...

The Americans are under the impression that brand new Virginia-class boats will be relevant for 30 years. Are you suggesting they won't?
 
So, the naval reactors would have to be sealed by the US or UK inside the submarine hulls before they came to Australia, remain sealed throughout the 30-year life of the submarine and be removed by the US or UK at the end of that life. That means if the submarines are to be built here, a section of the hull and reactor would need to be built in the US or UK and then moved to Australia. Or, if that is not feasible, then a reactor could possibly be imported into Australia, but with no Australian personnel having access to it at any time, something which would presumably need to be verified by the IAEA in some way that would also not give inspectors access to the reactor.

Can't see that working very well.

To be fair, that's how the British got started.
 
The same can’t really be said of the Astutes with greater risk of support issues given the much smaller UK Astute fleet and that it’s intended production run and service life re: the UK will end rather sooner. And given the small size of the UK Astute fleet and the pressing demands closer to home likely that any UK Astute visits Australia will be rather more infrequent and briefer than their US equivalents.

While the British have largely been absent east of Suez since joining the EU, they have long standing commitments with Australia, Brunei, Malaysia, Singapore, New Zealand, and the United States in the Pacific. Now, having left the EU, and the increase in security concerns, there is a likelyhood of a return to greater cooperation, and a more persistent presence, in the region. I posit that we have seen the first three steps in that direction this past year.

The Queen Elizabeth Carrier Strike Group traversing the South China Sea loaded with UK and US F-35Bs then conducting big deck drills with US and Japanese carriers I view as the first tangible step. Building an aircraft carrier is a feat. Having friends from a large number of countries meet you halfway around the world to perform complex interoperability excercises is power projection on an entirely different level. This was not a one-and-done.

The AUKUS agreement is the second. While each of the three countries enjoy special relationships with one another, the closeness of the UK/US submarine cooperation cannot be overstated. This relationship and (IMO) the return of the UK to the Pacific in a meaningful way, necessitated this agreement. I view AUKUS as an extension of existing US agreements with Australia to now include the UK and eventually provide support for interoperability between UK, US and Australian military assets in Australia - including submarines.

The Reciprocal Access Agreement with Japan signed by the UK in May (and by Australia in January) is the third. By removing (or at least simplifying) legal and logistical barriers, providing access to one another’s equipment and facilities, training and deployment challenges can be prepared for and mitigated. This will allow greater ease for more frequent UK deployments to Japan.

These agreements require a tremendous amount of effort to attain. The Australian RAA with Japan has been under negotiation since 2014 for example. I don't expect the UK has made these committments for infrequent and brief visits.

But we shall see what we shall see.
 
The UK withdrew from East of Suez before they joined the European Community/ EU.
Joining the European Community/ EU was part of trying to find a role in world after imperial decline and after making many of these post-imperial-type of decisions.
This cause and effect relationship appears to be widely misunderstood in the UK.
And the UK could have done AUKUS even if they were still in the EU.

And the UK has rather more pressing concerns a lot closer to home re: Russia, instability in neighbouring regions to the UK and to the EU, etc. And that’s before considering economic problems, etc.

While I am sure that the UK can contribute to Pacific security in close alliance with the US, Australia and other regional allies. geography, limited resources and other inevitably higher priorities will influence and to some extent limit the types and “weight” of contributions they can realistically make on a sustained basis in this area.
The UK can hopefully remain a significant player but it can’t just magically return to being a world power when it isn’t one and hasn’t been one for more than 60 years at least.
 
IMHO, basing US/UK subs in Oz while training and placing crew members from the RAN would enable training and facilities to come on stream in a controlled manner rather than everything being done flat out and making mistakes. It will take quite some time to bring crews up to standard. if rushed, where would crews come from? Stripped from the surface fleet?

I concur. Would it not make sense to begin training for the new boats with net-new recruits?

Buying current designs will reduce the relevance of what is supposed to be a fleet with long term relevance, wasted money in other words.

Well...

The Americans are under the impression that brand new Virginia-class boats will be relevant for 30 years. Are you suggesting they won't?
Training will I believe have to involve all levels of service life. Some of the junior ratings already serving will become chief of the boat etc in the future and type specific training will better prepare them for that.

As for the Virginia class boats, mea culpa, I had the impression that they were closer to the Astute class boats in age and developement potential. I got it wrong, sorry folks.
 
Well Ben Wallace's recent comment that they are likely to devote a CSG to NATO means its less likely that a carrier will be sailing the Indo-Pacific regularly now.
HMS Prince of Wales is already nominated NATO Flagship and since both carriers are likely to be operated on rotation the options would seem to be fleeting visits as and when opportunity allows. Geopolitics has shifted a little since AUKUS came out of the Defence Review, it remains to be seen how much of the strategic pivot will shift eastward.

Still only got five SSNs at the moment, won't get the full eight for a good few years yet, but by the 2030s there is no reason why there wouldn't be a greater presence of Astutes in the region.
 
The UK withdrew from East of Suez before they joined the European Community/ EU.
Joining the European Community/ EU was part of trying to find a role in world after imperial decline and after making many of these post-imperial-type of decisions.
This cause and effect relationship appears to be widely misunderstood in the UK.
And the UK could have done AUKUS even if they were still in the EU.

And the UK has rather more pressing concerns a lot closer to home re: Russia, instability in neighbouring regions to the UK and to the EU, etc. And that’s before considering economic problems, etc.

While I am sure that the UK can contribute to Pacific security in close alliance with the US, Australia and other regional allies. geography, limited resources and other inevitably higher priorities will influence and to some extent limit the types and “weight” of contributions they can realistically make on a sustained basis in this area.
The UK can hopefully remain a significant player but it can’t just magically return to being a world power when it isn’t one and hasn’t been one for more than 60 years at least.
I know people will disagree but the UK was hardly a power in the proper sense of the word before WW1. Being a one trick pony does not make one a 'power'. I would argue that a world of contributors is leagues ahead of 'power' nations where the conduct and secure and cogent development of defence assets fails. A UK that is more member than leader, imho, makes the UK MORE relevant rather than less. No, I know that is NOT what you said but I think you know what I mean.
 
Seems like someone is worried:

It's factually incorrect. SSN reactors don't contain weapons grade material.

And technically the Queen is still head of state in Australia, so it already has nuclear weapons. In fact Western Australia is where they were tested back in 1952. So it isn't proliferation even if they came with nukes. And seriously, China is worried about Australia owning nukes when the DPRK already does?
 
Seems like someone is worried:

It's factually incorrect. SSN reactors don't contain weapons grade material.

And technically the Queen is still head of state in Australia, so it already has nuclear weapons. In fact Western Australia is where they were tested back in 1952. So it isn't proliferation even if they came with nukes. And seriously, China is worried about Australia owning nukes when the DPRK already does?
Actually it is theorized in open source that the initial Virginia reactor (and likely Astute as well) is or is close to weapons grade; this is why it never needs to be refueled. Presumable at some point during the usage the core falls below weapons grade, but I think it does start out that way.


That said, clearly the PRC is just whining for the sake of whining, since that country is vastly ramping up its own nuclear force.
 
Actually it is theorized in open source that the initial Virginia reactor (and likely Astute as well) is or is close to weapons grade; this is why it never needs to be refueled. Presumable at some point during the usage the core falls below weapons grade, but I think it does start out that way.

It must mean like 20% or something (normal reactors are ~5%). I can't see it being 90%, I don't know how that would work without serious problems.
 
Actually it is theorized in open source that the initial Virginia reactor (and likely Astute as well) is or is close to weapons grade; this is why it never needs to be refueled. Presumable at some point during the usage the core falls below weapons grade, but I think it does start out that way.

It must mean like 20% or something (normal reactors are ~5%). I can't see it being 90%, I don't know how that would work without serious problems.

I believe it’s actually over 90% but I think it’s one of those things not explicitly stated. Apparently they poison the reactor with some kind of compound that inhibits the reaction that slowly burns off as the purity drops to give a relatively steady power output.
 
Interesting read:


Naval reactors (with the exception of the ill-fated Russian Alfa class described below) have been pressurised water types, which differ from commercial reactors producing electricity in that:
  • They deliver a lot of power from a very small volume and therefore most run on highly-enriched uranium (>20% U-235, originally c 97% but apparently now 93% in latest US submarines, c 20-25% in some western vessels, 20% in the first and second generation Russian reactors (1957-81)*, then 21% to 45% in 3rd generation Russian units (40% in India's Arihant). Newer French reactors run on low-enriched fuel.
  • The fuel is not UO2 but a uranium-zirconium or uranium-aluminium alloy (c15%U with 93% enrichment, or more U with less – eg 20% – U-235) or a metal-ceramic (Kursk: U-Al zoned 20-45% enriched, clad in zircaloy, with c 200kg U-235 in each 200 MW core).
  • They have long core lives, so that refuelling is needed only after 10 or more years, and new cores are designed to last 50 years in carriers and 30-40 years (over 1.5 million kilometres) in most submarines, albeit with much lower capacity factors than a nuclear power plant (<30%).
  • The design allows for a compact pressure vessel with internal neutron and gamma shield. The Sevmorput pressure vessel for a relatively large marine reactor is 4.6 m high and 1.8 m diameter, enclosing a core 1 m high and 1.2 m diameter.
  • Thermal efficiency is less than in civil nuclear power plants due to the need for flexible power output, and space constraints for the steam system.
  • There is no soluble boron used in naval reactors (at least US ones) but boron may be a burnable neutron poison in the fuel.
  • A submarine reactor is required to withstand the shock and vibration experienced by all warships in active service due to ocean turbulence and enemy action.
* An IAEA Tecdoc reports discharge assay of early submarine used fuel reprocessed at Mayak being 17% U-235.

The long core life is enabled by the relatively high enrichment of the uranium and by incorporating a 'burnable poison' such as gadolinium – which is progressively depleted as fission products and actinides accumulate and fissile material is used up. These accumulating poisons and fissile reduction would normally cause reduced fuel efficiency, but the two effects cancel one another out.

However, the enrichment level for newer French naval fuel has been dropped to 7.5% U-235, the fuel being known as 'Caramel', originally developed for research reactors and providing the possibility for greater fuel density, so helping to minimize the increased size of an LEU-fuelled core. It needs to be changed every ten years or so, but avoids the need for a specific military enrichment line, and some reactors will be smaller versions of those on the Charles de Gaulle. In 2006 the Defence Ministry announced that Barracuda class submarines would use fuel with "civilian enrichment, identical to that of EdF power plants," about 5% enriched, and certainly marks a major change there.

Long-term integrity of the compact reactor pressure vessel is maintained by providing an internal neutron shield. (This is in contrast to early Soviet civil PWR designs where embrittlement occurs due to neutron bombardment of a very narrow pressure vessel.)

The Russian, US, and British navies rely on steam turbine propulsion, the French and Chinese in submarines use the turbine to generate electricity for propulsion.

Russian ballistic missile submarines as well as all surface ships since the Enterprise are powered by two reactors. Other submarines (except some Russian attack subs) are powered by one. A new Russian test-bed submarine is diesel-powered but has a very small nuclear reactor for auxiliary power.

The smaller US Virginia-class SSN submarine first commissioned in 2004 has has a S9G reactor of about 210 MW driving a 30 MW pump-jet propulsion system built by BAE Systems (originally for the Royal Navy). The reactor does not need refuelling for the 33-year service life and can operate with convection circulation without pumps. The vessels are about 7900 dwt submerged, and 19 were in operation by mid-2021, with more being built – a total of 28 from initial contracts. In 2019 ten larger Block V versions (25 m longer, 10,800 dwt) were ordered for delivery 2025-29, costing $22.2 billion for the first nine. These are effectively a new class.

The 14 US Ohio-class SSBNs (and four converted to SSGNs for guided missiles) have a single S8G nuclear reactor of 220 MWt delivering 45 MW shaft power. These require mid-life refuelling at about 25 years. The 12 slightly larger Columbia class to replace these will require no refuelling, hence shorter mid-life maintenance (2 years instead of 4). They will have an S1B nuclear reactor with electric drive (without reduction gears) and pump jet propulsion. They have been developed in collaboration with the UK, which will deploy them as Dreadnought-class SSBNs.

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The Rolls-Royce PWR1 of about 78 MWt was used to power the first 23 British nuclear submarines. It was based on the Westinghouse S5W reactor, one of which was provided by the US Navy in 1958 under a mutual defence agreement. The PWR1 with high-enriched fuel required refuelling every ten years or so. British Vanguard-class ballistic missile submarines (SSBNs) of 15,900 dwt submerged have a single PWR2 reactor with two steam turbines driving a single pump jet of 20.5 MW, implying a reactor power of about 145 MWt.

UK Astute-class attack submarines of 7400 dwt submerged have a modified (smaller) PWR2 reactor driving two steam turbines and a single pump jet reported as 11.5 MW. The first of seven vessels was commissioned in 2010, and five were delivered by mid-2021 at a cost of £1.65 billion each. New versions of this with 'Core H' will require no refuelling over the life of the vessel, about 25 years*. In March 2011 a safety assessment of the PWR2 design was released showing the need for improvement, though they have capacity for passive cooling to effect decay heat removal.

* Rolls-Royce claims that the Core H PWR2 has six times the (undisclosed) power of its original PWR1 and runs four times as long. The Core H is Rolls-Royce's sixth-generation submarine reactor core.

The PWR3 for the Vanguard replacement Dreadnought-class SSBNs will be largely a US design – presumably based on S9G in the Virginia-class – but using UK technology. It will be more expensive to build but cheaper to maintain than the PWR2. All UK submarine reactors use highly-enriched fuel, obtained from the USA.
 
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Say what you want of Admiral Hyman Rickover caracter (he could be a stubborn dickhead at times) he certainly knew what was needed to power a submarine. Also safety credentials.
In passing, the one and only USN submarine ever powered by a liquid metal reactor - he instantly hated it, for good reasons, and ensured it never, ever happened again. The Soviets demurred and went full bore with liquid metal reactors submarines. It cost them an arm, a leg, and lots of sailor lives, plus a crapton of money - for nothing, or next to nothing. Stellar top speed maybe, but at what cost ? the Alfas were fast but they were also maintenance dogs. Most insane aspect was the necessity of running the reactor 100% of the time otherwise the coolant froze into a granite-like stuff and the submarine had to be scrapped.
 

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