Submarines are always a great topic to write about. Much about the silent service is – for good reasons – kept out of the public eye, to the extent that it makes “normal” operational secrecy seem rather transparent. This leaves ample room for speculation, but at the same time even submarines have to follow the laws of physics, geography, and international relations, meaning an honest and constructive discussion usually will provide interesting insights, as people are bound to reach different conclusions based on the same limited information. So with that framework laid out, let’s kick it off.
The Dutch submarine replacement program for the Walrus-class has seen a winner (or, at the very least a ‘provisional winner‘) with French Naval Group and their Blacksword Barracuda. The program and decision is interesting in many ways, so let us start from the beginning. And let us start by making one thing clear:
I have no idea which submarine would be the best option for the Koninklijke Marine.
The Walrus-class started its life as a rather troublesome project. Construction on the lead ship started in 1979, but it took until 1992 before the submarine was commissioned – the time in between had seen amongst other things both the original shipyard going bankrupt and a serious fire. Still, despite this the eventual submarine proved rather successful, and according to all accounts the class has given stellar service both at home and abroad. The Dutch aren’t stupid, and realised quite some time ago that the class would need to be retired at some point – in particular as only ordering four submarines meant the force had shrunk compared to the 80’s and left the individual subs rather busy. Unfortunately the replacement program faced a number of delays, and depending on exactly when you started counting the announcement last week was at least a year and a half late, though an argument can be made that the delay is closer to a decade (the original plan back in 2014 called for the replacement to be in service by 2025, which is, you know, next year…).
One of the key factors influencing the design is the Dutch Caribbean. The Netherlands still includes half a dozen islands in two distinct groups in the Lesser Antilles. These are home to almost 340,000 inhabitants in a part of the world that hold a number of potential flashpoints as well as issues caused by non-state actors. The ability to project power in the defence of these calls for a submarine able to make a cross-Atlantic transit and then operate in a reasonable manner when on station. This is in no way beyond the scope of reality – the Germans and Italians tried this in practice during WWII, with the 1,100 t Type IXC U-156 in fact targeting Aruba specifically – but it is a scenario rather unlike what most European conventionally powered submarines are designed to do. In addition, while the Dutch East Indies are long gone, the long shadow of history means that the country does have significant interests in the region as well as in the Indo-Pacific at large. Add to this an increasingly assertive China also occupying an ever larger role in the plans of European navies, and a submarine able to transit major oceans before doing something useful might come in handy – even if it would require basing in the region.
As such, the basic design criteria of the Walrus-replacement submarine was approximately 3,000 t displacement, the ability to fire both cruise missiles and torpedoes, as well as an operating range and transit speed allowing for operations in the Caribbean. In addition, delivery time is key, as was the ability to get Dutch industry involved in the programme.
There are two submarine classes that fit the design criteria rather well. One is the Japanese Taigei-class, which comes in at 3,000 t and is designed for the vast Pacific Ocean where range and endurance are key. Another feature which really sets the Taigei apart is the use of lithium-ion batteries, significantly increasing battery capacity of the submarine (Korean yards talk about 160 % greater cruising range for Li-ion-batteries compared to standard lead ones, though the graphic they use actually show a more modest but still significant 60 % increase). It lack an integrated cruise missile, though it is able to fire the UGM-84L Harpoon from its torpedo tubes and as recently as earlier this month Naval News got a quote from Admiral Ryo acknowledging that, yes, the Navy is indeed looking at fitting new subs with vertical launch systems (VLS) for the Tomahawk-cruise missiles in line with Japan’s earlier Defense Buildup Program.
The other submarine that roughly does what the Dutch want is the South Korean KSS-III program which sports two sub-classes differing in that the Batch I (which are in service) are a bit shorter and lighter, while the Batch II (currently being built) are larger and include lithium-ion batteries for their AIP-systems. The reason behind the change in size is that the Batch II sports ten ballistic missile tubes instead of six for the Batch I, and before anyone starts screaming about Tridents and other nuclear-armed SLBMs it should be pointed out that the KSS-III has the purely conventionally armed Hyunmoo-IV-4. The submarines are also able to fire cruise missiles, and that seems to include land-attack capabilities in addition to anti-ship ones, though to be honest the rather opaque world of Korean missiles means I won’t say I’m certain. Even in the Batch I-form the submarine at roughly 3,300 t surfaced displacement is somewhat larger than the Dutch target, though notably the reported length of 83 meters is actually a meter shorter than the Taigei, while also sporting a crew complement of just 50 compared to the 70 of the Japanese sub.
And of course, neither submarine was under consideration for the Dutch requirement.
In part this comes down to the drawn out process. The region has seen changes when it comes to arms export policies in the last decade, and the first KSS-III Batch I submarine, the Dosan Ahn Changho, was launched in 2018 and commissioned in 2021, while the first Taigei hit the water in 2020 and was commissioned only two years ago. As such, it is fair to acknowledge that neither existed besides on paper when the original 2014-version of the Walrus-replacement program started.
Which also happens to be the case for all submarines down-selected by the Netherlands, to this very day.
The four designs offered where an enlarged version of the German-Norwegian Type 212CD (designated 212CD E), an enlarged version of the Swedish A26 Blekinge-class (designated C718), the Spanish S-80 Plus Isaac Peral-class, and a shrunk conventionally-powered version of the French Barracuda/Suffren-class. The one which didn’t make the cut was the S80 which still was in production at that time, and which would have been the only submarine with another country ordering the same design as well. It is hard to blame the Dutch, though, as the S-80 has had its fair share of issues, including being overweight to the extent it required a lengthening of the hull. That left the three paper-proposals in the running, and crucially it wasn’t so much that the specific version of the submarines proposed didn’t exist, but even of the baseline submarines both the 212CD and the A26 are still only in production, while the Barracuda is only found in the nuclear-powered version.
This part deserve some more attention, as swapping out a nuclear propulsion system to something else is hard. A good comparison is switching from a prop-driven system to a jet engine for aircraft, which, yes, did happen twice in operational service, but only twice. The markedly different working principles of the nuclear-steam turbine setup compared to the fuel cell-AIP means we end up with completely different layouts and space requirements. We can nicely illustrate this difference with the cutaways of two of the submarines mentioned above, the Suffren and the KSS-III, courtesy of H I Sutton.
The KSS-III as seen in the cutaway which first appeared in the Naval News article “Game Changer: AIP Submarine Has Fired A Ballistic Missile For The First Time” shows a fuel cell equipped submarine. Note the kind of stretched out machinery space, which isn’t overly high, and the large number of battery cells which are spread out throughout the submarine.
This in turn is the Suffren, which also sport no shortage of batteries. It does, however, have a nuclear reactor driving steam turbines (and producing electricity) which are responsible for the shaft turning (the Suffren in fact has a hybrid propulsion system, which also sports two generators and two electric engines as an alternative running mode). As is evident, the setup is rather different, and the reactor itself dominates the space between two bulkheads. For more on the Suffren, you can head over to Sutton’s homepage.
That’s the general layout, to which comes the different needs for cooling and fuel, both of which lead to openings in the pressure hull, the designs and installations of which are something you are supposed to treat with care. Then comes the shape of the hull, which you generally optimise for things such as planned operating speed, which again is something that differ between SSNs and SSKs.
All of these things are manageable, but in essence once you redo at least half of the interior of your submarine and changing its length, displacement, and performance, you are in fact creating a new submarine class. Something which the Australians are acutely aware off, because as we all know, they did in fact buy a conventionally powered Barracuda. And then ditched the whole project after years of issues with finalising the design, only to start looking at SSNs together with the US and the UK. As I have noted in my earlier comments on the whole debacle, much of the blame belongs with the Australians who wanted an SSN, bought an SSK, and then got really upset when what they got wasn’t an SSN. However, it is also clear that the Shortfin Barracuda did run into a number of issues, and the question is can the Blacksword get around these?
There are some things to suggest it indeed could. To begin with, one would assume that the five years Naval Group spent trying to get the Shortfin Barracuda from the concept phase into the real world will have resulted in at least some usable design work (though mind you, the Shortfin Barracuda was much closer in size and displacement to the Suffren compared to what the Blacksword will be). In addition, the French yard will apparently keep much more of the work at home this time around, which should ease the actual workflow. There are also signals, albeit weak, that the Dutch will be happy to accept a configuration closer to the French one compared to what the Australians wanted. An example is that it seems like the requirement for a sub-launched Tomahawk have given way for a more general cruise missile-capability (Hello, MdCN!).
It should also be noted that while the Barracuda-conversion might become a headache, that could also be the case for making ever larger versions of SSKs. Again, ironically, the best example is Australia, where the rather successful Swedish A17 Västergötland-class got scaled up to become the Collins-class, which in turn suffered a whole host of issues. Again, it isn’t unreasonable to say that much of the blame rests in the land of the kangaroos, but notable is that this took place while Sweden still had a very active and internationally recognised submarine industry. This is as opposed to the current situation which sees Kockums in the process of building their first two newbuilds since the 90’s. The C718 might have been an outstanding design, but the fact that neither Damen nor Saab have a proven pedigree of building new submarines in recent times did carry with it a certain amount of risk. The local cooperation package with Damen did however on the surface seem to be superior to what either of the other submarines offered, and Sweden has a proven track-record of integrating things stamped “Made in the USA” onto different platforms around the world.
Damen has not taken the loss well, and the Dutch powerhouse has visibly mobilised since the rumour broke approximately a week before the announcement that Naval Group was about to take home the deal. They now pin their hopes to the fact that the parliament is the one making the ultimate decision, and in theory at least they can still turn it around. Would it make things better? Who knows, as noted none of the design on offer are yet in the water, and from the outside being able to accurately judge the merits of each bid is next to impossible.
On the German side, they have been rather successful both on the domestic and export market, but the Type 212CD still hasn’t touched the water (though production did kick off last year). However, TKMS has a proven ability to build not only submarines – Naval Group certainly has that as well – but they also have a submarine in production that closely matches what was offered to the Netherlands. According to a quote Naval News got from the yard the ‘E’ in ‘CD E’ would have been no more dramatic than a hull plug for additional fuel capacity and accommodation spaces, which if true really would have made the sub a low-risk option, and I’m prepared to say the only submarine of the three down-selected to not be a unique class. The big benefit would then have come in the fact that the Dutch order would actually have been part of a longer series, and not just a four-strong class as is now set to be the case.
It’s hard to overstate the value of this last factor. Submarines are complex to design, and difficult to build. A significant part of the cost is in fact not the welder fusing two plates together, but the design work and getting used to how you actually build the submarine. The latter is its own process, and all this add up to mean that the first few vessels of any class are overly expensive. Exactly where things start to look rosier is an open question, but somewhere between three and five vessels is a place where things tend to turn around. Of course, with most navies these days struggling to find not only procurement budgets, but also operating budgets and having issues with crew recruitment and retention, not many navies are buying half a dozen submarines of any given class. With the Type 212CD already having firm orders for two boats for Germany and four for Norway, that class has however already turned the corner. In addition, both countries are also discussing additional batches, with four to six German and six Norwegian boats in total not looking unreasonable. Add to that four 212CD E, and you have something as rare as a European submarine class of ten to sixteen sisters!
INTERLUDE: This also makes the Swedish decision to buy just two A26-submarines such a strange one, as I have noted earlier. In essence they are paying for the expensive part, but stopping short of ordering the numbers where the investment would start to really pay off. Additionally, with the Dutch order now apparently having sailed, and with little indication Canada will be interested in a Swedish-Dutch sub that has scored two and zero buys respectively at home, the export market is starting to look grim for the A26. Poland's Orka-program is still ongoing, but has more twists and turns than your average roller coaster, and I wouldn't count too much on that in my books. As such, for the A26 to realise its full potential, at the very least ordering a second batch of another two boats is an obvious thing to do. And for the time being, no one else but the Swedes are likely to order them. Luckily, it makes perfect sense in many ways for Sweden to do so:
As described above, it is sometime around when you build your fourth boat in a series that you actually start getting some return on your investment, meaning that HMS Småland and HMS Öland would in all likelihood be measurably cheaper to build (getting back towards the originally envisioned ~500 MEUR a piece in inflation adjusted unit cost might be doable), and they would also make maintaining and upgrading the whole class cheaper,
If Sweden wants to maintain their ability to build submarines - which is a capability they have officially identified as strategically important - they really do need to ensure they have continuous work for the yard (you can ask the Australians or Dutch how easy it is to start from scratch once you have let your submarine-building know-how atrophy),
From an export point of view, ordering a second batch would both put pressure on the price (acquisition and life-cycle cost), while also signal confidence in the design in a way ordering just two doesn't,
For the Swedish submarine force, the current plan is to have the two A26 replace the two upgraded late 80's vintage A17-class boats HMS Södermanland and HMS Östergötland (already retired and mothballed). This will give a five-boat fleet of two A26 Blekinge-class and three A19 Gotland-class, stemming from the mid-90's. If the Swedish politicians are as serious about growing the Armed Forces as they like to say, going back to where they were in 2004 before the Navy sold off half their A17 to Singapore is certainly low-hanging fruit (and at seven submarines it would still leave the Swedish submarine force smaller than it was at any point between 1915 and 2004).
Back to the Dutch, it should be noted when discussing economics of scale that Naval Group has an SSK in their portfolio, and one which has sold well that is. The Scorpène-class is found in a number of different sizes, with the Brazilian ones going up to 2,000 t in size. There is however the question of whether it would scale to the kind of design the Dutch are after, and it is in general an older design. Regarding the cost of the French design, the price has also been quoted as being one of the key reasons behind the decision. This has in turn lead to charges of an uneven playing field, as Naval Group’s majority shareholder is the French state, and comments about subsidies are flying around. This is a nice rallying cry for the losers, but let’s not pretend either the 212CD or the A26 are the results of any kind of a Smithian free market.
So, what happens now? The Dutch will likely get one of the most capable non-nuclear powered boats this side of the South China Sea, but they will almost certainly pay a premium both in acquisition and operating costs doing so, and there’s certainly ample room for the kind of technological risk that tend to set these kinds of programs back a few years. With the stated schedule being two boats delivered within a decade of contract signing, I’m not sure that’s a bet I’d be willing to take. And getting there for the Walrus-class means that two out of the four boats will be retired and used for spares. A not overly nice option in a decade seemingly set for high tensions around the world.
Corporal Frisk 