Royal Australian Navy Discussions and Updates 2.0

Going Boeing

Active Member
I was aware that the AUKUS SSN is planned to have payload tubes but the number has not been announced. At the time that the plan was announced, there was a drawing released showing 3 tubes along the centre line behind the sail but it was not considered an official configuration.

One possibility is, if the AUKUS SSN ends up with a similar diameter hull to the Dreadnought class, then it could be configured with the same “Common Missile Compartment“ of 4 payload tubes as fitted to the Columbia & Dreadnought classes. While that hull diameter might be considered too large for an SSN, it would result in a lot of commonality of systems components in the RN fleet and reduce the amount of design work for the SSN.

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SammyC

Active Member
I'm not sure the intention is to structure the AUKUS SSN as an SSGN.

Retaining all four CMCs with 16 tubes for the AUKUS represents about 116 TLAMs (If the Ohio conversion is anything to go by, each Trident tube I think held about 7 TLAMs after modification).

It makes for a rather large submarine and that adds to cost, complexity and I suspect some reduction in operational capabilities. Note the block 5 Virginias are about $0.5-1B more than the block 4s and take a lot longer to build, as a result of the VPMs.

SSNs are primarily ASW and ASuW, land attack remains an ancillary function. For the Brits, they are principally used to protect the SSBNs, so stealth, manoeuvrability and speed are most important, rather than missile capacity.

I think there is a place for something like the earlier block 4 Virginias with a smaller number of VLS tubes (say 12-24, so maybe one CMC style system), as this provides a modest strike capability without impacting torpedo capacity. More than this I would suggest starts to compromise other functions.

I actually think there is more of a place for something like the dry deck shelter fitted to some of the Virginias. The wild card remains how they will be configured to house and work with UUVs. I would view this as a must.

I can see the AUKUS SSN would be the same diameter as the Dreadnaught class (simply to house the same reactor) and to have a great deal of commonality, but that does not mean it will the same length.
 
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SammyC

Active Member
I may not have expressed it clearly but, I was thinking that the AUKUS SSN could have one CMC of 4 payload tubes whereas the the Dreadnought will have 3 CMC’s (12 tubes) and the Columbia will have 4 CMC’s (16 tubes). I was mainly indicating the potential for a lot of commonality with systems in the Dreadnought class.
Ahh, OK. Yes I think that is a reasonable proposition.
 

Scott Elaurant

Well-Known Member
Previously the Government had only announced $10B in infrastructure investments ($8B WA, $2B SA), so there is another $8B of stuff to be built that has not been publicised. That's a lot of money on top of the other investments in port, maintenance and construction facilities, so it will be interesting to see what this is earmarked for (I can't think of what other infrastructure would be needed, any thoughts?).
This is only an educated guess but ultimately I expect the following will be required, each costing billions, to complete a fully sustainable SSN capability:
- upgrade FBW to support SSNs including stores, basic maintenance and crew accommodation and training facilities (already included in $8B WA upgrade)
- upgrade ASC to a nuclear engineering standard, including containment structures, uprated shiplift, enlarged build shed, and crainage etc designed to radiation resistant standard. Surely this will cost more than $2B budgeted so far for ASC.
- construct new FBE fitted to support SSNS similar to upgraded FBW (similar or larger cost than $8B for FBW)
- long term storage and disposal facility for nuclear waste, logically in SA. RAN SSNs at end of life could be dismantled and reactors removed at ASC if facility is upgraded to nuclear engineering standard. Note that Naval Group do this at Cherbourg, where they build their new SSNs. That is where the required skills are located.
 

SammyC

Active Member
I remember thinking when Aukus and SSNs for Aus were announced that I wonder what had changed in the forecast that pushed SSN being a better option than the Attack Class planned and worth the high risk / high cost process that SSNs would require. Sure, I expect there are many reasons including political, but this passage from Marles about expecting snorting subs to be more detectable in the coming future as one of those reasons is very interesting.

Ref: Transcript from ABC News Breakfast

Bold emphasis & truncation my own:
I've been pondering this for a bit. It seems reasonable that AI combined with expanding high resolution satellite imagery, and perhaps more advanced acoustic detection, could locate submarines that are snorting, at some point in the future (say 10-15 years). So this is plausable.

It does however beg the question why other nations intend to persist with diesel-electric designs. I believe the Canadians are considering long range submarines, but are only considering diesels, and the Japanese are building their latest class the Taigei with diesels (albeit with nice big batteries). Both nations have similar requirements to Australia, particularly extended range and underwater speed. Both are wealthy enough to afford nuclear.

One would think that if Australia had this view on future SSK stealth concerns, other nations (such as Canada and Japan) would be thinking along the same lines. At the moment it appears they are not.

The logical conclusions here are that either they disagree with this forecast, they intend to use their submarines differently (such as for coastal protection, rather than expeditionary surveillance), they see more promise with AIP systems, or they don't see a way to nuclear options.

It will be interesting to see how this space develops. Some other articles I have read indicate that the Japanese are seeking VLS capability on their next generation subs. This suggests they want an underwater strike option that necessitates long range ocean traversing. I struggle to see how this could be fitted on a diesel platform. I wonder if they would join a future AUKUS SSN build.
 
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SammyC

Active Member
This is only an educated guess but ultimately I expect the following will be required, each costing billions, to complete a fully sustainable SSN capability:
- upgrade FBW to support SSNs including stores, basic maintenance and crew accommodation and training facilities (already included in $8B WA upgrade)
- upgrade ASC to a nuclear engineering standard, including containment structures, uprated shiplift, enlarged build shed, and crainage etc designed to radiation resistant standard. Surely this will cost more than $2B budgeted so far for ASC.
- construct new FBE fitted to support SSNS similar to upgraded FBW (similar or larger cost than $8B for FBW)
- long term storage and disposal facility for nuclear waste, logically in SA. RAN SSNs at end of life could be dismantled and reactors removed at ASC if facility is upgraded to nuclear engineering standard. Note that Naval Group do this at Cherbourg, where they build their new SSNs. That is where the required skills are located.
Thanks Scott, I had forgotten about the intention for an east coast submarine base. Given it will need to be built from scratch, yes it will be expensive.

I had also not considered the need for decommissioning facilities, also likely to be expensive.

I agree, I would have thought the Osborne yard would cost more than $2B.
 

Scott Elaurant

Well-Known Member
I've been pondering this for a bit. It seems reasonable that AI combined with expanding high resolution satellite imagery, and perhaps more advanced acoustic detection, could locate submarines that are snorting, at some point in the future (say 10-15 years). So this is plausable.

It does however beg the question why other nations intend to persist with diesel-electric designs. I believe the Canadians are considering long range submarines, but are only considering diesels, and the Japanese are building their latest class the Taigei with diesels (albeit with nice big batteries). Both nations have similar requirements to Australia, particularly extended range and underwater speed. Both are wealthy enough to afford nuclear.
….
It will be interesting to see how this space develops. Some other articles I have read indicate that the Japanese are seeking VLS capability on their next generation subs. This suggests they want an underwater strike option that necessitates long range ocean traversing. I struggle to see how this could be fitted on a diesel platform. I wonder if they would join a future AUKUS SSN build.
I’ve been thinking about this too. This is only speculation, but I think it is technically feasible. One option for detection could be new satellites capable of chemical detection, which might be able to detect the diesel plumes from a snorting diesel submarine. These have been developed for peaceful purposes (detecting greenhouse gas emissions) using shortwave infrared sensors.

Point detectors (in low earth orbit) can now identify point sources of methane, dust or greenhouse gases emitting as little as 0.1 tonnes/hr and accurate within 60 metres. There are both wide area and point search satellites already in orbit. Obviously, these could be tasked to sweep oceans and locate snorting submarines by detecting their diesel plumes. With large scale computer processing this could be done similarly to satellite scanning for surface ships.

If this is correct then snorting will become detectable within a few hours of data processing, assuming the sea you are in is being scanned. An AIP or large battery SSK that can remain submerged will still be undetectable. So for short range missions where diesel speed or range is not required an SSK will still perform well. So no problems in the Baltic or for Japanese or Korean SSKs going into the Japan or Yellow Seas. But for a Collins transiting from Perth to Indonesia it would be a problem.

My apology if this seems too speculative but my point is we already have the technology now to do this. It would just be a case of connecting together the components with some good data processing to form a system, then testing and calibrating it till it works.
 
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