SSN-AUKUS Future Astute Replacement (2030s) (RN) [News Only]

[SKB]

Introduction
The Aukus-class submarine or SSN-AUKUS (previously known as SSN(R) and the Maritime Underwater Future Capability (MUFC)) is a planned class of nuclear-powered fleet submarine (SSN) intended to enter service with the United Kingdom’s Royal Navy in the late 2030s as a replacement for the current Astute class, the last of which will be delivered in 2026. In March 2023 it was announced that the Royal Australian Navy would join the programme under the AUKUS agreement to replace their ageing Collins-class submarines.

The submarine will be powered by a Rolls-Royce pressurised water reactor (PWR).


Development
The initial concept phase of the programme was scheduled to last for three years. This phase had begun in early 2018 but was suspended for two years due to delays in the Astute-class and Dreadnought-class delivery programmes. In 2020, the Ministry of Defence recruited for a Submarine Delivery Agency Project Manager to work on the SSN(R) design and development process.

In March 2021, the government’s defence paper Defence in a Competitive Age committed to funding the SSN(R) project. This was followed in September 2021 by an investment of £170 million by the government in the form of two £85 million contracts to BAE Systems and Rolls-Royce Holdings for early design work on the SSN(R). The investment will support 350 jobs for the UK economy.

In November 2022, MSubs Ltd was awarded a £15.4m contract to build an XLUUV (Extra Large Uncrewed Underwater Vehicle) vessel which is to be delivered to the Royal Navy within two years. The 17-tonne vessel (known as Project CETUS) is described as being "the next step in developing autonomous underwater warfare capability" and is also to feed into the design of SSN(R).

In January 2023 it was reported that the submarines were likely to incorporate a vertical launch system (VLS) for land-attack missiles. This would be a first for Royal Navy SSNs, which currently launch land-attack missiles via their torpedo tubes. A VLS system was described as likely to increase interoperability options with the US Navy since future US land attack missiles may not have a horizontal launch option.

The design was renamed SSN-AUKUS in March 2023 when Australia joined the programme and additional US technology was incorporated, both as part of the AUKUS agreement. The British Prime Minister Rishi Sunak announced in March 2023 that the U.K. would boost defense spending by additional £5 billion over two years, some of which would go towards funding "the next phase of the AUKUS submarine programme." The submarine will be powered by a Rolls-Royce pressurised water reactor (PWR). BAE Systems at Barrow in Furness will lead the construction of the submarine in the United Kingdom and Australia. As of 2023, the workforce there was being expanded from 10,000 to 17,000 to support both the Dreadnought-class submarine program and the AUKUS submarine. While a signficant component of the work was likely to be undertaken at Barrow in Furness, the Osborne Naval Shipyard in South Australia was also reported as likely to be engaged in a major part of the work.

The March 2023 joint leaders statement indicated that: "In the late 2030s, the United Kingdom will deliver its first SSN-AUKUS to the Royal Navy. Australia will deliver the first SSN-AUKUS built in Australia to the Royal Australian Navy in the early 2040s".

[SKB]

https://www.navylookout.com/nuclear-sub ... e-options/

[Jensy]

Judging by the silhouette, it looks like my dream of 'Shortfin Dreadnought' (Dreadless Class) might yet have a chance of coming to pass!

Not sure what to make of us exporting Astute, considering the DefSec's rather scathing remarks in the Summer about trying to build any more for the UK.

I suppose the final two Trafalgars will be completely knackered by their OSD, PWR-1 obsolescence aside?

[ArmChairCivvy]

I suppose the final two Trafalgars will be completely knackered by their OSD

3-strong fleet over those years is a distinct possibility; but then again, how long did Vanguard stay 'in dock'?

[Lord Jim]

Well as there will be little actual news on the SSN(R) programme for a while I thought I might highjack it for an idea that popped into my head. It is often stated that we cannot build any more Astutes as the Dreadnought programme is to supersede it at Barrow. This is true and then the RAN SSN programme began. What do people think of the idea that if the Astute design won, the UK helps fund the infrastructure that Australia want to build to allow the construction of its own SSNs. If this produced a slight increase in capacity, could the RN purchase a number of improved Astutes similar to what the Australians would be building, calling them the Astute Batch 2. Yes the construction would be carried out in Australia but Barrow would be flat out building and finishing the Dreadnought class and when finished could then take over building the Astute Batch 2 or building its successor to replace the Astute Batch 1s. Rolls Royce would be producing the Nuclear powerplants for both RN and RAN boats and if a open architecture CMS etc. were used the RAN could use its preferred US system and the RN could use a development of that used in the Astute or Dreadnought. Australia could even able to accelerate its programme later with the capacity that was being used to build the RN boats, and everybody saves as components would be being purchased in larger quantities than if both we stand alone, even more so if common with some of those being purchased for the Dreadnought class reducing the risk of obsolescence. Everybody wins. Just a few ideas out of the box.

[serge750]

Sounds like a good approach, Oz gets more experience building more boats, UK gets more boats - even 1 more Astute for the RN would be good, as usual all comes down to the funding.....

[inch]

All sounds good in theory but sorry to bust bubbles but I think in my opinion that Australia Will Go with the US design over the astute for lots of reasons , although I would love them to choose otherwise and be secretly fingers crossed right up to the actual announcement which one they are going for ,but the US option has too many pluses compared to the astute ,and uk capacity ,lack of numbers compared to Virginia class , ongoing developments thru program life, sticking to the big player's design not the low numbers bit player' , although that's no reflection on how good the astute is ,just the numbers game ,plus Virginia already regularly operations and to some extent facilities in the area compared to astute , etc etc etc ,

[wargame_insomniac]

All sounds good in theory but sorry to bust bubbles but I think in my opinion that Australia Will Go with the US design over the astute for lots of reasons , although I would love them to choose otherwise and be secretly fingers crossed right up to the actual announcement which one they are going for ,but the US option has too many pluses compared to the astute ,and uk capacity ,lack of numbers compared to Virginia class , ongoing developments thru program life, sticking to the big player's design not the low numbers bit player' , although that's no reflection on how good the astute is ,just the numbers game ,plus Virginia already regularly operations and to some extent facilities in the area compared to astute , etc etc etc ,

I think Australia going for mainly US subs seems most likely. I hope that Australia might buy some UK systems so that we benefit too, but I think the bulk of the deal will be with US. The US is planning on building 66 Virginia Class versus just 7 Astutes for UK, and then Barrow switching to the Dreadnought SSBN.

Firstly the US still has a load of Los Angeles class that they are slowly retiring, so they could easily give /sell several to Australia. Even if low on remaining uranium, RAN could still use one as a moored training boat and others for service at sea.

Secondly if US shipyards are able to consistently start building 3 new Virginia Class subs every year, they can build two for the USN and one for RAN.

[Scimitar54]

So you think that 27 years to build both the USN SSNs and the RAN SSNs would be ok then?
This would add 5 years to the last USN boats. The USN cannot get its own Virginia class boats fast enough. So US yards could not build the RAN boats, even if Australia was happy for them to do so. Both US & UK would face challenges if their design was chosen.

Fortunately however, Australia wants to be able to build, operate and maintain (as far as possible) their own SSN.
The questions are:-
- Which design would best suit the Australians ? (Size & Crewing requirements)
- Will the required deliverables for both US & UK designs be deliverable both on cost and in the
required timeframes ?

The UK production facilities do not provide the RN with the number of SSN needed, whereas the US facilities do provide the USN with what they require. If we need to upgrade our manufacturing facilities to produce sufficient PWR3 for the RAN boats, then it makes sense to ensure that we upgrade our facilities to enable the production of additional SSNs for us as well.
I am sure that the US (and the USN) would greatly welcome us gaining the potential to provide something in the order of 5 additional RN SSNs (The Australian requirement giving the impetus to the required investment and infrastructure) which would also benefit the UK and RN strategically.

[tomuk]

The USN cannot get its own Virginia class boats fast enough.

The UK production facilities do not provide the RN with the number of SSN needed, whereas the US facilities do provide the USN with what they require.

Um I thinks that's a bit of a contradiction. It is my understanding that the USN want more SSN than are currently being built and better boats than the Virginias too.

For proliferation/ITAR reasons I think the answer to/reason for AUKUS will be PWR3 powered Astute Batch 2 (or 3 or 4 )/SSN(R) Batch 0. Boats built in Australia fitted with UK built reactors. The Australians\Americans will bank roll the necessary expansion at Rolls Royce/Barrow

[Lord Jim]

The issues I see is that the version the RAN will want of the Virginia Class will be substantially different from what will be being built for the USN at the same time. I do still see the operation of SSNs being mainly an aspiration for the RAN rather than a definite result.

[jedibeeftrix]

Since where talking about AUKUS and the Ozzie sub-gap in the 2035-45 timeframe - could they lease a few Tagai subs as Collins class start to shuffle off this mortal coil?

https://en.wikipedia.org/wiki/Taigei-class_submarine

[SD67]

Replying to Jim above - the problem with Astute batch 2 is that PWR2 is finished and PWR3 is fatter than the hull. Astute with PWR3 is no longer Astute. It would be easier to make Australia into the SSN(R) program. The timelines actually such quite well, build starting mid 2030s,

In terms of Australia going Virginia - I’m sceptical. It’s a completely different manufacturing process, all set up for mass production. Then there’s the crewing issue, and the sheer size of the thing.

[Timmymagic]

Since where talking about AUKUS and the Ozzie sub-gap in the 2035-45 timeframe - could they lease a few Tagai subs as Collins class start to shuffle off this mortal coil?

The Collins Class MLU should get them through that period. They weren't worked that hard in their early years, like the Upholder Class in Canada they're not as old as their years suggest.

Replying to Jim above - the problem with Astute batch 2 is that PWR2 is finished and PWR3 is fatter than the hull. Astute with PWR3 is no longer Astute. It would be easier to make Australia into the SSN(R) program. The timelines actually such quite well, build starting mid 2030s,

I think SSN(R) works perfectly for Australia. Lower crew, large capable sub focused on ASW and intel gathering. Timings work well as well. If we husband our Astute fleet (which the delays in build have meant has happened by default) there's no reason that we couldn't work together.

Then there’s the crewing issue, and the sheer size of the thing.

Regarding the Virginia Class, the manning issue would be problematic, but I don't think the Australian's would be interested in the Block V with the extra VPM. If they were getting anything it would be a Block VI or VII, which will probably be shorter than Block V with just the forward VPM, but with additional 'seabed engineering' and UUV support built in. Outside of the US and China no-one can really afford to fill all of those VL tubes anyway, and the UUV support and 'seabed engineering' will be a requirement of the Australian's as thats definitely more in their mode of operations than operating as an SSGN. To be competitive the SSN(R) will need those capabilities to interest the Australian's.

[Dobbo]

I’d imagine that the U.K. Submarine building industry should aim for a fairly straightforward build cycle. Over a 30-35 year period they should aim to design, build and deliver 4x SSBN and 10-12x SSN for the RN.

Anything less than that would likely mean disruption on the scale we saw with Astute and anything faster than that would likely mean major investment in capacity.

From the perspective of industry, the question is whether, if the Aussies want in on SSN(R), they want the U.K. to build all 8 boats or part of the boats, or just the reactor or all of some boats but parts of others. It’s all very complex.

Say the U.K. orders 10x SSN(R) and the Australians order 8, it would be difficult for the U.K. to build 10 complete boats but only parts of 8 more. There are a lot of moving parts.

It’s a different beast from collaboration on the T26 and possibly the T83 programme… building SSNs is not really the sort of thing you can easily drag work home for some pork barrelling…

[Dobbo]

I remember reading that the review after the issues with the Astute programme recommended the optimal drumbeat of submarine production to be one every 18mths for the UK (balanced by skills, facility capacity, supply chain etc). If a nuclear reactor is designed to run 24 years without refuelling then that would suggest an optimal fleet size of 16 (SSN & SSBN) subs.

[SD67]

IMHO that’s the “natural” state of the fleet. Last T class was commissioned 1991, HMS Astute 2010. We missed at least 5 SSN worth of construction, while skilled tradesmen were driving taxis around Barrow or (lucky ones) lining up lucrative gigs in the North Sea

[jonas]

Could collaboration be a possibility :-

https://www.shephardmedia.com/news/nava ... tary-says/

[SW1]

Sounds one of the more sensible procurement decisions as would prioritising submarines over surface vessels

[Dobbo]

I think if the view is taken that the requirements of the AUKUS participants in very complex systems such as SSN, Air and Ballistic Defence Cruisers/Destroyers, ASW are substantively aligned it may be that common platforms are suitable.

I’m the case of SSNs there is a clear need for the RN to have additional units in the next build cycle, and for that industrial base to increase to meet those. For Australia they need the capability but have no industrial base at all for such a project and no desire for a civil nuclear programme. This will be a challenge and as such I can see a how the construction of SSN(R) for RN and RAN takes place in Barrow with certain systems constructed in Australia as part of a work share agreement (presumably without undermining the UKs sovereign capability).

[SW1]

I would suspect final assembly and commissioning would be a pre-requisite for each of the 3 nations and common hull fabrication techniques in each country.

the boat design and major sub systems would likely be what is shared around with the most specialist sub systems (reactor, pulsor, sonars, masts) likely being made in U.K. and US

If there is a payload module similar to the Virginia class that is a good candidate for being nation specific and either inserted or left out depending on financials.

[Dobbo]

Some comments from the RUSI paper on what might be deliverable with a 3% of GDP defence budget. Irrespective of whether you think 3% is right or deliverable it provides interesting benchmarking.

https://static.rusi.org/354-OP-from-fam ... nal1_0.pdf


Comments on SSN(R)

“Accelerate next-gen SSN, improved weapon systems, aim at 10 submarines”

“Carrier + FCAS long-range missiles, prompt-strike hypersonic for SSN”

“• In announcing to NATO’s June summit that the UK was now on track to be spending 2.5% of GDP on defence by 2030, Boris Johnson referred to the additional costs of AUKUS for the UK. This is a reference to the need for serious extra spending on a new generation of SSN to replace the Astute class – the SSN-R. Depending on the extent to which Australia decides to develop its own new SSN in cooperation with the UK, it is possible that large parts of this programme could be a joint venture, potentially including production, weapon systems, training and infrastructure. The added funding included here would allow the MoD to proceed at pace to build this new generation of SSN. It could also be used to increase the size of the SSN fleet from 7 (the current level) to 10. This would increase the UK’s ability to deploy worldwide, including in the Indo-Pacific, while maintaining the levels necessary to counter Russian threats in the North Atlantic and the Arctic.”

[wargame_insomniac]

Some comments from the RUSI paper on what might be deliverable with a 3% of GDP defence budget. Irrespective of whether you think 3% is right or deliverable it provides interesting benchmarking.

https://static.rusi.org/354-OP-from-fam ... nal1_0.pdf


Comments on SSN(R)

“Accelerate next-gen SSN, improved weapon systems, aim at 10 submarines”

“Carrier + FCAS long-range missiles, prompt-strike hypersonic for SSN”

“• In announcing to NATO’s June summit that the UK was now on track to be spending 2.5% of GDP on defence by 2030, Boris Johnson referred to the additional costs of AUKUS for the UK. This is a reference to the need for serious extra spending on a new generation of SSN to replace the Astute class – the SSN-R. Depending on the extent to which Australia decides to develop its own new SSN in cooperation with the UK, it is possible that large parts of this programme could be a joint venture, potentially including production, weapon systems, training and infrastructure. The added funding included here would allow the MoD to proceed at pace to build this new generation of SSN. It could also be used to increase the size of the SSN fleet from 7 (the current level) to 10. This would increase the UK’s ability to deploy worldwide, including in the Indo-Pacific, while maintaining the levels necessary to counter Russian threats in the North Atlantic and the Arctic.”

10 SSN for RN sounds great but first RN will need to increase number of crew, whether improved cres recruitment or retention). At the moment the RN can only crew six boats, with Trenchant and Talent decommissioned in May before Anson was commissioned this week.

[SD67]

But doesnt the Astute have a smaller complement?

If anything Australia will have a bigger problem given the tightness of the Oz labour market - self driving trucks are now being used in the West Australian mining industry

[wargame_insomniac]

But doesnt the Astute have a smaller complement?

If anything Australia will have a bigger problem given the tightness of the Oz labour market - self driving trucks are now being used in the West Australian mining industry

Sure - I believe it was 130 for Trafalgar vs 98 for Astute.

So we had to decomission two boats to save 260 to be able crew one boat for 98 - where have the other 162 crew gone then? I am not sure when Agamemnon is due to comissioned but presume it will be 1-2 years away.

I don't know if there were other specific reasons that both Trenchant and Talent needed to be decommissioned at the same time? I could have understood decommissioning just Trenchant to transfer the crew over to Anson prior to her commissionin. But not losing both which now leaves us with just SIX SSN!!