February 10, 2022

Debate Continues: US or UK SSN: Common AUKUS Design?

Anonymous commented on February 9, 2022:

“It appears that the RAN is looking at Astute but with the S9G reactor from Virginia. The PWR3 reactor will not physically fit in Astute (too wide) & the PWR2 is no longer manufactured (also has potential safety problems & only lasts for 25 years without refuelling). 

The Virginia is narrower, so it will physically fit in the hull, but is longer (the reactor system), so will require a reshuffle. Hence the 18 month study of options. 

If Astute can be made work (with a US reactor), then it should be the front runner. Otherwise it would be a AUS deal (no need for UK with a Virginia deal). The big advantages of Astute is lower crewing, similar operating methodology to RAN & available jigs etc that are no longer useful to UK & more to come available as the last Astutes move through the system.”

Pete Comment

I’m undecided about the above. We will probably keep on guessing years after the Australian Nuclear-Powered Submarine Taskforce https://www.defence.gov.au/about/taskforces/nuclear-powered-submarine-task-force  presents its 18 month tentative findings around April 2023.

My tentative views are the future Australian nuclear sub (Aus SSN) will already be one third US intellectual Property (IP) due to the US Lockheed Martin Integrated Combat System (sensors, databases and weapons).

There may be an additional US third, the US manufactured S9G reactor.

This, is to date, specifically built for the final US third, ie. the US Virginia submarine hull with many attendant contents.

All this suggests, maybe, Australia will choose a US designed submarine. 

Crystal ball gazing:

Maybe the UK may use a heavily S9G based “PWR4” for post 2026 late model Astutes or for earlier than intended UK planned SSN(R) new class.

Maybe the US Virginia, "Improved Virginia" or "SSN(X)" would have added sufficient labour-saving devices for a smaller crew by the 2030s 

OR Australia accepts the current US 135 submariner crew requirement 

OR Australia may have its own smaller crew practices.

OR

Maybe, though less likely, the US, UK and Australia will manufacture a common (US, UK, Aus) agreed AUKUS SSN design to be used by all three navies?

8 comments:

Abao said...

As an outsider I always wonder why Nuclear and not LIB Diesel submarines? Advances in LIB might make it possible to get a large seagoing submarine that only needs to recharge it batteries intermittently or in safer waters?

Anonymous said...

If fitting the S9G reactor to the Astute turns out to be a viable solution then this seems a sound way to proceed. It is sensible to do this preliminary technical feasibility work before signing an agreement.

If it fails I agree the RAN should then proceed with a Virginia design, in which case my personal preference would be fore the Block 4 or Block 6(?) designs rather than Block 5, which is more expensive in order to provides a capability Australia has not sought.

This is exactly what should have happened with the Naval Group offer to confirm the feasibility of converting the Barracuda to a diesel design before signing a $50 billion contract. Then we would not have wasted five years. Also, if this is true, and this is what is being done with the £200 million UK design work announced by Boris Johnson soon after AUKUS, note the quantum of the cost (approx. $400 million Au). This is far less than the design phase was costing with the French option, and Australia paying this cost as part of a modified Astute purchase would be a reasonable price to pay for the UK IP.

If it works the AUKUS spec Astute would be in some respects superior to the original. The S9G reactor has a reported 32 year life without refuelling compared to “approximately 30” for the UK PWR2. It also has a higher rated power output, so could be quicker, though that might also require some upgrading of the engines. But that is possible at this stage.

Pete said...

Hi Abao

SSK with LIBs 4 knots for 3 days.

SSN 30 knots for 3 months.

Pete said...

Hi Anonymous [at Feb 11, 2022, 9:04:00 AM]

I've responded in article https://gentleseas.blogspot.com/2022/02/us-ssn-for-australia-seawolf-20-vs.html

of February 11, 2022..

Regards

Pete

Anonymous said...

Pete

PWR3 is already heavily based on the S9G. It’s just that PWR3 was never intended to have to fit in Astute. S9G has to fit in Virginia & was designed accordingly.

Pete said...

Thanks Anonymous [at Feb 11, 2022, 10:15:00 PM]

So will the SSN(R), the UK follow on, use a PWR2 with a new core, or is there a PWR4 in the works?

Cheers Pete

Anonymous said...

The stated aim, when AUKUS was announced, was to commence building a proven “off the shelf” design as quickly as possible. To select the Astute class and then have to redesign it to accept the S9G reactor and the AN/BYG system with US sourced weapons will add a lengthy design period before construction can begin - this is not compatible with the original plan.

Additionally, the Astute class does not have any vertical launch capability and this will restrict its ability to be upgraded throughout its entire life. Virginia Payload Tubes have so much flexibility that they should be considered to be essential fit for the RAN SSN’s. The weapon options in these tubes include Tomahawk missiles, future Hypersonic missiles, mobile mines, etc as well as housing equipment & delivery vehicles for Special Forces.

USN manning levels always have significant amount of redundancy so an establishment manning reduction would be an option for the RAN, at least until the recruiting & training systems catch up to these higher levels.

Looking at the planned timeframe for the construction of the RAN submarines, they should be looking at building “off the shelf” Virginia class submarines - the first 4 built to Block VI specs but standard length with 2 VPT’s in the bow and the second batch of 4 built to Block VII specs with the stretched hull containing an additional 4 VPT’s per hull.

Just my thoughts.

Pete said...

Thanks Anonymous [at Feb 21, 2022, 4:14:00 PM]

“off the shelf” is certainly needed.

Its struck me that the "Task Force" https://www.defence.gov.au/about/taskforces/nuclear-powered-submarine-task-force feature a photo of a UK (Astute) sub to avoid the Greens' + ALP Left's mantra of "Australia should not be dominated by the US". Hence no US Virginia displayed.

I'll turn your comments into an article later this week.

Regards

Pete