Royal Australian Navy Discussions and Updates 2.0
- Thread starter OPSSG
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Nope. Refueling the French SSNs takes 5 months from initiating reactor shutdown to completing light off and unplugging from shore power. It's designed into the SSN design, with the appropriate hatches etc and happens as part of a broader docking period concurrently with other maintenance operations, so the net impact on availability is less than that (also some of those steps are necessary parts of US SSN maintenance periods anyway, even without refueling, which further reduces the difference).
The net result is that the French SSNs spend more days at sea and have higher availability than their US/UK peers or small SSKs, even with 4 refuelings over their 36 year lifespan (Rubis SSNs), and the new Suffren SSNs will do better with shorter annual maintenance periods and 1 less docking/refueling over their lifetimes. So the LEU route does not require more subs - if anything it could even require fewer subs than Aukus if the option of double crews was implemented as per French practice.
I know the other issue people get hung up over is the shore-based implications of LEU, but with 30+ countries operating civilian nuclear plants (including tiny Finland & Slovakia... population 5 million!), 12+ countries operating enrichment facilities (including allies such as Japan, the UK, US, Netherlands, France etc), and of course Australia being a top 5 producer of uranium, the practical and sovereign complications of sourcing, handling, and storing LEU are much less than being handcuffed into a US partnership that may or may not pan out in a decade and having to deal with long term storage of spent HEU fuel (albeit that problem won't happen until 2050+).
P.S. I know this ship has sailed, I just have a strong reaction to this idea that "no we had no other option than Virginias because those were the only SSNs that would work for us" when in fact the technical pros & cons of LEU vs HEU are much more nuanced IMHO ;-)
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Big_Zucchini
Well-Known Member
Choosing an arms supplier is always a political decision. The only way to get around this is independent production. Is Australia willing to spend over 5% annually and wait decades until it can produce pretty much anything short of silicon domestically?
That's not a rhetorical question. If it's willing, I'm more than happy seeing democracies fortifying.
If it's not willing, it just has to swallow the pill of buying foreign stuff.
Whether it's Israel or someone else really doesn't matter. Now it's supplier A that's a scandal, then it's supplier B, then you find yourself writing off any friendly supplier just because of some Chinese influence campaign.
Every supplier has their own niche. Israel's niche is providing modern capabilities in an affordable package. This is something that's critical when you're looking to increase capacity, which is the current focus in the west.
It's also possible to just pick the US as the sole foreign supplier, cut a deal with politicians to never trash on the US no matter what, and worst case just pay quadruple on certain munitions. But is it politically feasible to come to such arrangement?
Alternatively, in the age of ToT and domestic production everywhere, you can just buy foreign equipment, have it assembled by a local company, and call it Australian. The politicians who do anti-army campaigns usually don't understand enough in such matters to find out.
Australia has operated civilian nuclear plants since 1958. Only one at a time, & only small reactors for research, production of medical isotopes, & the like, but it's just coming up to 67 years & 2 months - on Saturday. Not been any significant problems AFAIK. The current Argentinean (yes, really! Argentina designs & sells small reactors - look up INVAP) reactor has been operating satisfactorily & safely for 18 years & 3 days so far.
I'm glad someone appreciated my math ;-)
To resolve some of the uncertainties over reactor usage, I dived into command histories of US SSNs (available on history.navy.mil and elsewhere).
1) Typical USN SSN deployments are 35,000 - 40,000 nm over ~6 months, with 70-80% of time underway and average speeds of advance of 11.5 to 12 knots
2) Over longer durations, including training and patrols in home waters, speeds of advance are somewhat lower (as would be expected ), approx. 10 knots
3) Over a 10 year operational cycle, average miles steamed is ~35,000 nm/year between major overhauls (SSN 690 Philadelphia - Los Angeles class)
4) Over the long run, including time spent in major overhauls, US SSNs average ~25,000 nm/year (500,000nm over 20 years for SSN 750 Newport News, 650,000nm over 25 years for SSN 684 Cavalla).
My takeaway: these numbers are in the same ballpark as the numbers I previously quoted for French Rubis class SSNs (40,000 nm/year during operational cycles, 33,000nm/year over 35+ years, 10 knot average speed of advance). If anything the Rubis class were used slightly more intensely in terms of distance travelled and time at sea (not really surprising with double crews), so even if their transit distances and speeds are lower, it all balances out. Their 240,000nm reactor life between refueling was sufficient for 6+ year operational cycles (French Optempo), which would be more like 7 years with the USN Optempo above. Take that and multiply by 1.25x to 1.5x for the Suffrens with their expected 10 years before refueling (or between refuelings? Not the same).
So anyway, bottom line is I'm not seeing any evidence of hugely different Optempos or deficiencies in LEU reactor life that would cause operational limitations.
One could of couse do sensitivity analyses around each of the variables above but it won't fundamentally change the results IMHO... because whether the cycle ends up being 7 years of high intensity operational use (e.g. with double crews) or 9-10 years of lower intensity operational use, the basic message is that even an LEU core with a 300,000+ nm life gets you significant mileage - enough to pack in multiple deployments and several hundred sea training days and enough to maintain a USN Optempo (or better). With ~3 refuelings needed for a 30+ year life, which are low impact and could all happen during regular docking periods.
(Again apologies for flogging a dead horse - but I hope some find these SSN op cycle details interesting)
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iambuzzard
Well-Known Member
Worse than a Virginia under RAN colours, better than a Virginia under USN colours. Worse than an AUKUS SSN in the 2040s, better in the 2030s.
24 tube launched weapons… not enough for some, but potentially 23 more than what you need to ruin a Chinese carrier’s day.
Basically one probably shouldn’t compare sub A vs sub B based on weapons fit only, without weighing all the other relevant factors that go into getting it to right place at the right time to fire those tubes.
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downunderblue
Active Member
I don't think he's commenting on that, purely on the life cycle of the LEU reactor when compared in a French Marine nationale vs RAN context.
I was mentioning that it may be a reason why CoA/RAN flatly refused to consider the Suffren prior to committing to AUKUS. Whether or not it is relevant is unknown as the whole process is classified so we can only guess. I like his use of math though and going down the rabbit hole which I often find myself doing, likely due to the ADHD mind I have (as others may attest too here as well ...)
downunderblue
Active Member
Lol you replied at the same time I did.
Yes there are many factors and we can only guess as I reference above. It seemingly didn't take 'them' long to say goodbye to NG as an option.
Whilst the LEU reactor is an issue on refuelling, don't ignore the nuclear proliferation argument aligned with the lack of a domestic nuclear industry to help refuel it (reducing sovereignty).
But again we can only guess. The French 'baby was thrown out with the bath water' and it's 'full steam ahead' with Aukus pillar one (that's 1A, not B, C, D or E, ok!).
When I have the time I'm going to stop using colloquial phrases as they are inflact lazy use of english but I am time poor atm, so be it!
iambuzzard
Well-Known Member
Depends on what block the Viginia class SSN is. The below is from Wikipedia but gives you an idea of the differences.
The RAN Virginia class won't have the VPM.
Block I–II:
12 × vertically launched missiles:
12 × VLS tubes (for Tomahawk cruise missiles)
25 × torpedo tube launched torpedoes & missiles
4 × 21" torpedo tubes (for Mk-48 torpedoes or UGM-84 Harpoon missiles)
Block III–IV:
12 × vertically launched missiles:
2 × Virginia payload tubes, each capable of launching six cruise missiles (12 × Tomahawk BGM-109)
25 × torpedo tube launched torpedoes & missiles:
4 × 21" torpedo tubes for Mk-48 torpedoes or UGM-84 Harpoon missiles
Block V-VI
40 × vertically launched missiles:
4 × Virginia payload modules (VMP), each capable of launching seven cruise missiles (28 × Tomahawk BGM-109 and future guided cruise missiles)
2 × Virginia payload tubes, each capable of launching six cruise missiles (12 × Tomahawk BGM-109)
25 × torpedo tube launched torpedoes & missiles:
4 × 21" torpedo tubes for Mk-48 torpedoes or UGM-84 Harpoon missiles
StevoJH
The Bunker Group
I
I’m fairly sure (not 100%) the block IV’s were one of the ones commissioned around 2018 or 2019, but I can’t remember where I read that.
The RAN is supposed to get two mid-life Block IV, plus a Block VII without VPM.
I’m fairly sure (not 100%) the block IV’s were one of the ones commissioned around 2018 or 2019, but I can’t remember where I read that.
Another ABC article poking at the DoD.
www.abc.net.au
Australian navy's newest boats made in China
A new fleet of tug boats that the Defence Department ordered for the Royal Australian Navy has been secretly built at a Chinese shipyard under a $28 million contract awarded last year to a Dutch company.
www.abc.net.au
One is under sovereign Australian control. The other is subsidized by Australia (crew, maintenance, shipbuilding) but with no guarantees of anything in return (under the current US admin and any future Republican admin... President JD Vance anyone?).
Without delving too far into politics, I can give you the anecdotal example of a Republican friend of mine, ex-US military, who is seriously considering working for Vance or running for Congress. He's educated, highly qualified, not a MAGA nutcase, and probably very representative of where the Republican party is heading in a post-Trump world. He will flat-out tell you that the US has no national interest in defending Poland, shouldn't be investing in NATO, and probably won't be able to defeat China. I don't think that kind of world view bodes well for AUKUS in the long-run.
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Andrew Greene use to be a respected defence journalist.Another ABC article poking at the DoD.
Australian navy's newest boats made in China
A new fleet of tug boats that the Defence Department ordered for the Royal Australian Navy has been secretly built at a Chinese shipyard under a $28 million contract awarded last year to a Dutch company.
John Fedup
The Bunker Group
Trump’s plan would seem to be to largely withdraw from the world stage economically and militarily and focus his attention on North America. Bad luck Canada, Greenland and Panama.
This potentially puts Australia in an awkward position as we will have several nations wanting to step up in this region to fill any power gap that will be left if the Americans withdraw.
Mind you America still has holdings in this region so I doubt they will ever leave completely.
If the Americans do seek to reduce their presence in this region under Trump there is no guarantee that a future administration would reverse that decision.
Huge challenges for Australia, Japan, Korea and other regional powers under that scenario.
iambuzzard
Well-Known Member
Musashi_kenshin
Well-Known Member
Realistically the US' and Australia's geopolitical needs will remain the same for many decades. If the US gave up on both Europe and the western Pacific, Australia would be in a heap of trouble with or without SSNs.
That's why the rotational visits by the USN and RN are important, because it increases the amount of Allied submarines in the area and helps get the RAN used to operating and supporting them.
As for the Rubis, I'm sure it's a non-starter for Australia. They're old, small, have a limited endurance and I'm not sure if they can fire the Mk48.
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