October 10, 2017

Some (likely) Naval Group Approaches to Australia's Future Submarine

After much discussion on Submarine Matters (here and here) and elsewhere on the direction Naval Group is going with Australia's Future Submarine...

Some observations are:

Descriptions of a huge 50 year to design, build and upgrade submarine program are made by different people, at different times, for different purposes, targeting different audiences.

Disruptions to the future submarine selection process made it difficult for the Royal Australian Navy (RAN) and contestants to nail down final submarine requirements and designs. Up to February 2015 then Prime Minister Abbott unilaterally chose Japan. From February 2015 a selection process hid the reality that Japan was quietly still the winner. Japan was ahead until Abbott was removed from the Prime Ministership in September 2015. Once Prime Minister Turnbull was appointed the field was opened up to the 3 contestants (Germany, France and Japan) with a normally 3 year submarine selection period being compressed into 7 months (September 2015 to April 2016).

Turnbull chose to rapidly publicise the Future Submarine winner on April 26, 2016 in order to win South Australian votes in the early July 2, 2016 National Election. With the pork barrel of a $50 Billion project mainly at Osborne, Adelaide, South Australia Turnbull’s submarine-to-win-the-election-strategy succeeded in getting his government over the line by one crucial electorate/district/seat/vote.

Naval Group (then DCNS) had to publicly react quickly to Turnbull’s premature (April 26, 2016) announcement with as positive and concrete a submarine package as possible. For example Naval Group’s concept submarine was termed the “Shortfin Barracuda Block 1A” to indicate to the public that it was a solid building block in a highly developed submarine program. Shortfin was also presented as a conventional outgrowth of an already highly developed Barracuda nuclear submarine program.

Final Issues To Be Decided In Years To Come

In fact in a huge submarine program specific submarine characteristics can only be assessed and finalised once a finalised scale model can be hydro-dynamically tested or even after the full-sized first of class begins trials in the open sea (noise? cavitation?) in about 2031. Issues include:

-  length will fluctuate depending on many variables including the size of the bow sonar (Lockheed
   Martin (LM) input as one small part of its combat system) and whether a pump jet is added or
-  diameter could fluctuate (how many decks, bunk sizes and numbers, arrangement of how many
   torpedo tubes (LM), VLS? how many and size of diesels, batteries, fuel tanks, water ballast?
-  fuel cell AIP? inefficient to carry the LOX over Australia’s long transit distances, lack of
   observable French progress with Fuel Cell and lack of observable RAN interest
-  the first pump jet as standard on a SSK class. This would be a radical solution for the
   technologically conservative RAN 
-  RAN conservatism would also likely reject Australia becoming the second LIBs user after Japan.

At 8/10/17 5:13 PM someone with access to Naval Group thinking commented, in part:

“I think you will find that the [Australian Government] govt was well aware that both the DCNS & TKMS designs were just concepts (basic design only). Both required complete detailed design from scratch. Both would have used existing designs for reference (you don't reinvent the wheel unless you have to)...It will definitely be more like a conventional powered Barracuda than a stretched Scorpene (for a start you would have to stretch a Scorpene in all directions, not just make it longer)...”

A submarine builder’s technical design knowledge base, influencing future submarine designs, often goes back a century. The designs of the Scorpenes and Barracudas are only the latest. See the Table below.

Naval Group Submarine Development TABLE (by Pete)

(how many built?)
First Sub Laid Down
Last Sub Commissioned
Some still building?
Classes pre Agosta
26 Daphne
1863 the Plongeur 
1957 France only
many classes pre 1957
1975 France & Export
No. eg. WWI era. Interwar and WWII 
Redoutable SSBNs
6 built France only
1964 (1st commissioned 1971
Agosta SSKs
13 built
Early 1970s French, Spanish & Pak Navy
2006, 3 Spanish, 5 Pakistani remain
Rubis SSNs
6 built 2,500 tonnes
Re-commissioned as AMETHYSTEs
Rebuilds of the 6 existing Rubis SSNs
Triomphant SSBNs
4 built
Scorpene SSKs (14 total)
2 built---------------------
2 built---------------------
1 built so far

1999 O’Higgins Chile
2009 INS Kalvari India
2010 SBR-1-4 Brazil

2009 Malaysia
2016 (1st planned)
2020 (1st SBR-1)

5 x Kalvaris 1 per year
4 x SBRs (1 per year)
SN-BR SSN just 1 DCNS designing non-nuclear portion. 4 to 5,000 tonnes.
2024 (maybe) after the
Brazil building reactor.
2034 (or later) likely. Also depends on Brazilian economy.
1 in medium-long term
French only SSNs
6 planned
2029 for the last of the six
2052? Assuming all are SSKs? 1 built/2 years?
France’s Next Generation SSBN (SSBN NG)
4 likely
Armed with 10? to 16? M51.3 SLBMs

2050? Assuming one sub built every two years



Tri-ring said...

Somebody stated;
" It will definately be more like a conventional powered Baracuda than a stretched Scorpene (for a start you would have to stretch a Scorpene in all directions, not just make it longer)."

I believe this is too simple a response to a very complex situation, mainly weight balance.
Basically a nuclear reactor and it's supporting components would be the most heaviest within a SSN, simply removing it and replacing it with a diesel engine and the balance of the boat will be all out of whack with a front heavy sub since the reactor originally was near the aft section of the sub.
Unlike a land vehicle that only needs to move in 2D, a sub requires to move in 3D meaning balancing the boat is more critical to maximize power consumption moving vertically.
So you need to rearrange various other equipment to regain balance/center of gravity of the boat with all the piping and electrical systems realigned and before you know it you find yourself redesigning the whole layout making it a completely new design.
That is why I posted they didn't even have vaporware in the previous thread.

Ztev Konrad said...

France had previously laid down an experimental submarine as its first nuclear powered boat, the Gymnote (S655). However difficulties with the type of nuclear reactor they intended to use ( heavy water) meant it wasnt feasible so the design was reoriented for diesel power with 4 missile tubes in a humpback configuration to test their proposed SLBM's.

The more things change ...
Gymnotus is a type of fish that lives amoung tree roots or grassy meadows in tropical areas. It was the species famously tested by Faraday to establish the existence of an electrical current.

Anonymous said...

If pump jet stays in the Shortfin 1A design, LIB is essentially a must. LAB just does not provide the endurance that is necessary to drive the hull at 14kts for any appreciable distance. LIB will be a risk area since France is not exactly known to be at the forefront of LIB applied and material researches. 10-14kts is in the sweet spot of a pump jet before sonar goes blind. Lower than 10kts, you may as well stay with a skewed propeller.
It is stated that Shortfin uses a slightly shortened Suffren hull so the diameter of 8.8m is likely fixed. That is a much wider hull than Scorpene's 6.2m hull diameter. Scaling up the Scorpene diesel propulsion architecture will not be without risks. After all, Suffren has a 10kw electric motor while Scorpene has a 2.9kw motor.

Peter Coates said...

Hi Ztev

Thanks for discovering former French test submarine Gymnote. Its a real find I was unaware of.

https://en.wikipedia.org/wiki/French_submarine_Gymnote_(S655) indeed describes Gymnotes's North Korea-like use of a diesel-electric (DE) submarine for SLBM tests.

However for Australia to adopt LIBs Naval Group would need to transform, a full sized (meaning an available or built from scratch Scorpene) submarine for LIBs. Only the performance of a LIBs Scorpene could be compared with the full sized electric hotel+propulsion load performance of an already tested LABs Scorpene.
A miniature test sub or computer modelling would be inadequate.



Peter Coates said...

Thanks Tri-ring

With the total rearrangements you describe to achieve a conventional Australian Future Sub it may be easier and cheaper for France instead to deliver 6 nuclear propelled Barracudas to Australia.

The strategic threat level of Indo-Pacific oceans full of SSNs in 2030 will likely demand it (SSN armed Russia, China, friendly India) or SSNs/SSBNs on the way (North Korea, friendly Japan and South Korea).

Raw diesel-LAB electric (without AIP or LIBs) is increasingly proving a poor man's propulsion.



MHalblaub said...

Dear Ztev Konrad,
the Gymnote is prove a submarine can be changed but the Gymnote was an experimental submarine.

Insertion of AIP-sections are common with TKMS and Kockums.

Wikipedia gives no hint how massiv the Gymnote had to be changed. For a test vehicle some points are less important like e.g. endurance & weapons load. Especially torpedoes ~1.4 t of weight are nasty because they are much heavier than water (roughly twice as havy). A submarine has to keep the balance after firing 10 torpedoes and loosing 7 t weight.

Diesel is lighter than water (0.85 kg/l). An experimental submarine can trade diesel for balance and range.

Gymnote is not the best example to show that it is an easy task to transform an existing operational nuclear powered submarine into a Diesel powered one.


Tri-ring said...

Concerning my last post, it reminded me of the movie Das-boot where all non-essential men on board ran frantically from the stern to the bow of the boat to dive as fast as it can.
In other words even then they were working on a see-saw type situation where the weight distribution of the boat was made neutral making it possible for humans literally throwing their weight made a difference.
I don't think modern day subs will react the same way due to difference in overall displacement of WW2 era subs and present day ones BUT I do believe modern day sub designers follow the same principle they followed in the past to neutralize balance to make the boats as agile as possible to prepare for the worst.

Anonymous said...


In regard to your comment at the top of this page. I wrote the comment regarding conventional powered Baracuda rather than a stretched Scorpene. I am well aware of the points you raised (I find if I get too technical I loose a few people). If you read my original full comment( Pete only repeated part of it), you will find that I specificaly stated that you cannot just cut a Baraduda in half & weld on a conventional backend & pointed to the problems encountered by Spain with what in comparison, was a relatively straight forward stretch of a Scorpene (in respnse to someone who compared Shortfin to a stretched Scorpene). For those that are not aware - Spain tried to stretch a Scorpene design (their S80 sub), only to discover in the nick of time that they had made an error that would have made the sub unable to surface once it had dived. This has caused something like a 2-3 year delay. My argument is that both the DCNS & TKMS designs were both vapourware basic concept designs. Both required detailed design from scratch. Both would have used previous designs for reference.

The advantage for DCNS was that the Baracuda design was at least the approximate size required & was in production (hence the Shortfin uses similar dimensions to allow maximum reusage of design data). They also build diesel electric subs, so they are well aware of what they need to do to adapt (or combine if you like) the Baracuda & Scorpene to end up at Shortfin. The problem for TKMS is they have never built a sub of this sort of size before. Australia has. With the Collins class, which was done by a equally qualified designer (Kockums - recently owned by TKMS - now owned by SAAB) who had never built a sub of that size before either. So basically the problem for TKMS, is they were a bit too much like Kockums mark II & they no longer owned Kockums to allow them to argue we know what went wrong & won't make the same mistakes again. Been there, done that. (Not saying they could not have done it & if I was only building 3 I probably would have chanced it).

While I am a big fan of both Swedish & German engineering, I an understand why the Australian govt went with DCNS. Big subs don't phase them. Diesel electric doesn't phase them. Nukes don't phase them. While German fuel clell design is definately ahead, they have their problems just like other AIP's. The agument re LIBS & LAB are valid. Both France & Japan know this is the way to go. France, Germany, Japan, USA & Australia all have current research ongoing into LIB technology in regard to submarines. Japan will be the first to go live. Ask the Canadians about fires on subs (nothing to do with LIB's but a fire is a fire).It will be a few years yet re LIB's before we get a clear picture as to 'if we are there yet'. Changing from LAB to LIB is not a straight swap out afair. All of the players are aware of this. I fully expect Shortfin will be LIB at some point. It may be at boat 1 or at boat 4 but it will happen. I wouldn't even be suprised if we end up with a prop rather than a water jet propulsion (always was questionalble without a nuke to power it, but hey all the other designs had props anyway). The people involved in the selection were (for a change) well versed in subs. I doubt any of this is news to them (although this does not carry over to pollies).

Sorry to our internaional friends if I have use too many Australianisms.


Tri-ring said...

"The advantage for DCNS was that the Baracuda design was at least the approximate size required & was in production (hence the Shortfin uses similar dimensions to allow maximum reusage of design data). They also build diesel electric subs, so they are well aware of what they need to do to adapt (or combine if you like) the Baracuda & Scorpene to end up at Shortfin. The problem for TKMS is they have never built a sub of this sort of size before."

Boy talk about trying to spin the wheel.
You have the size of an SSN and weight distribution of a medium sized SSK and saying that is an advantage?
There is nothing in common between those two.
Let's get into details, the dimensions of an SSN is based on high speed maneuvering powered by a nuclear reactor which does not require to consider fuel economy, Australian asked for a diesel powered sub that can traverse long distance meaning slow transition speed with the best fuel economy.

1. Difference in patrol speed
2. Different fuel economy requirements
3.Complete different types of engine with complete difference in mass, dimensions and fuel type with complete different power train layout and sub components.

Out come of dimensions should change due to completely different criteria with complete different layout of equipments and subsystems within so to gain the right weight distribution for balance so there is NO adapting from one another with no reference from previous design except for the basics that is common on all subs making them alien to one another.
The details of the new sub will be completely different from either two and should be designated as a complete new design.

Anonymous said...


As I said, you cannot just cut a Baracuda in half & weld on a conventional rear half. DCNS have already said it will be a completely new design, not a conversion. They will however be using both the Baracuda & Scorpene designs as references where possible. The basic hull design will be based on the Baracuda, but I believe slightly shorter (2 meters). The basic hull design (regardless of what you put inside it) is one of the major design stages. You cannot just take a 2,000 ton hull & double its size. There are a whole lot of acoustic & hydrodynamic calculations & modeling as well as physical engineering that changes as the physical hull changes in dimension or shape. Anything that can be reused to speed up the design process is a good idea. The Baracuda hull already exists & is of a size at least somewhat comparable to the alternatives. All of the subs put forward were big subs (all bigger than Collins). The Soryu sub is 84 meters but needed at least a 6-8 meter plug bringing it up to 90-92 meters. The type 216 was 90 meters long. Baracuda is 99 meters, Shortfin 97 meters according to DCNS.

It is rare for any company to do a completely new design for anything unless they have to. Most things are evolutionary designs based on earlier designs for as long as you can get away with it. There is less risk & easier to work out a fix if the design changes are smaller than if they are bigger. It would take as much work for DCNS to design a 90 meter Scorpene (largest is currently 75 meters) as for TKMS to design a type 216 (largest current sub is 70 meters I believe). If the Baracuda did not aready exist, that's what they would have been putting forward. The Shortfin gave them a slight head start, an ability to say 'it will look just like this one, come & have a look, touch it if you want' & a basic hull design thats already been modeled & under construction & will be in the water before our design is finished. There is also the 'if you ever decide to get a few SSNs in the future we can do that too' (I believe DCNS have made mention of the possability if required).


Anonymous said...

On the bright side, they are not using Kobe Steel in their submarine hull. KQN

Peter Coates said...

Hi KQN (at 11/10/17 10:11 AM) on Shortfin with pump jet needing LIBs.

I don't thing Naval Group or Australian DoD would be able to contemplate using LIBs at this 2017 stage of knowledge.

Maybe in 2022 after assessing some years of Japanese LIB use will LIBs be considered for Shortfin (or not).