First Suffren SSN to be inaugurated on July 12th.
 

https://www.zupimages.net/up/19/28/7fun.jpg
https://www.zupimages.net/up/19/28/xwdm.jpg
https://www.zupimages.net/up/19/28/3kdr.jpg


The Suffren nuclear attack submarine will be set to water tomorrow in presence of the French president and his minister for armed forces. It is the lead class of its namesake class (Barracuda programme) and will have a 5,400 tonnes displacement, twice as much as the Rubis class submarines it replaces - the SSN featured in Wolf's Call, for the moviegoers here.


Using a hybrid nuclear-electric propulsion (running electric at low speeds and using its nuclear reactor for propulsion at higher speeds), it's going to be a revolution for the French MN, bringing its SSN to the most modern standards out there (an attention given to SSBN before with the Triomphant class). Much quieter, cruise-missile capable (using the French-made MdCN), faster and deeper-diving, it will replace the Saphir that just got retired from service a few weeks ago (built in 1984):


http://www.jeanpaulney.com/wp-conten...s-marin-11.jpg


Among the improvements, there'll be the pump-jet propulsion, the X-shaped dive controls as well as the option for a hangar to host a diver submarine propulsion system. The first crew, led by Commander Axel Roche, will take over the ship for trials in the next few days.


The seas welcome another boat.


EDIT: there's a very nice diaporama here. https://uk.reuters.com/article/uk-na...-idUKKCN1U61YR

The lightest of 4th gens :)

Also probably the last SSN class in the generation with maybe for exception of Chinese.

Always compact, but this time, our SSN will be larger than the old Surcouf (yes, the Rubis-class had a smaller displacement, amazingly so). Should make for a beast in coastal waters all around the world. Small, electric drive for low speeds, and the most silent torpedoes out there (the Black Shark and F21 use an entirely electric drive with new batteries that have a higher energy density than Otto fuels and such used in competitors, which should make for a paranoid's nightmare as they can creep on you from far away). Not the weapon load to fire dozens of cruise missiles at targets, but we don't really have the budget for that anyway!


But, yeah, it'll be the most modern class out there, and considering it was designed by the people whose previous boat went knock-knock with a British boomer because it was too silent to be noticed at literally point-blank range, I wouldn't be worried about its stealth.

France is not the only (or first) country using main hybrid electric drive for SSNs.

To be honest I think the displacement is more of a consequence of French requirements - for the minimal SSN, particularly armament wise.

As that navigational accident - have you ever seen a towed array on the French boomer?

IIRC, it's the first series-SSN to have one. I think a couple of boats were made with this during the Cold War by the US but with the technology left aside for not being good enough then. From what I see, only Tulibee and Glenard P. Liscomb ever used turbo-electric transmission, the solution having shown insufficient speed performance back then to be used in the LA class, and I haven't heard either Virginia or Seawolf having it. I think the Columbia SSBN will have a hybrid drive, though.


Maybe the new Russian boats have a hybrid drive, but I'm not aware of it, not having much information on these.

Heh, we're not planning to fight the entire Russian navy head-on. 24 weapons are enough for most realistic scenarios.
Problem with the "human error", "technological weakness" or "incompetence" scenario is that it also requires a Royal Navy boomer crew to fail just as hard. And if you think the Her Majesty's Silent Service is LARPing Down Periscope...

In the end, the fact is that a Vanguard-class SSBN on patrol couldn't notice its counterpart in time to avoid a collision. That alone should say a lot about the discretion of both boats.

Oh, and to your question, yes, the French boomer has a towed array, a DSUV 61B. Source (in French): http://www.assemblee-nationale.fr/13...a3809-tVII.pdf Search "DSUV" and you'll find the reference on page 216, the acronym SNLE being SSBN in French, while "antenne remorquée" means "towed array".

Yes, Kazan has been launched over two years ago and now is in trials. On previous generations the use of electric drive in any significant capacity was questionable, as per same signature reduciton requirements it was heavier/bulkier than the geared turbine.

Yes, that depends on your requirements, Brits did build a larger and more capable (atleast weapons wise) SSN though. Also use of low aperture cylindrical bow is a questionable choice.

Yes, it is in the documentation (thanks for the link etc), but have you ever seen a towed array housing? I haven't, which makes me curious.

OK, didn't know much for Russian subs. At least, it seems to be a new development for Western subs.
I don't know that much about the comparative advantages and drawbacks of spherical VS cylindrical, though I did remember reading about some advantages for the latter, at least for specific parameters. Though, yes, it'll depend on the requirements, and ours are pretty different from US and Russian ones, in that we don't really plan to fight massive naval battles: if a SSN of ours needed more than two dozen weapons, something would have gone massively, massively wrong and the next step would probably involve SSBN. It won't chase down a CVBG either or spam it with dozens of cruise missiles. OTOH, for projection capabilities, making sure noone tries a Falklands on us, or reminding secondary powers that buying a SSK or a SSN, even an advanced one, won't change the balance of power, or supporting the kind of operation we pull regularly? It's a superb tool, IMO. Plus, electric drive combined with F-21 torpedoes should make a lot of people paranoid. XD
I haven't either, but I haven't gotten close enough to our SSBN to say. And if its position isn't indicated on official pictures and documentation...

You didn't see any TA on french SSBN or SSN for one good reason, they are deployed / retrieved by a specialized ship called "Caudataires" when the sub leave or come back to l'ile Longue (base of the french SNLE) or Toulon (base of the SSN).


There is 2 of this specialized ship in service the Phaéton (Y 656) and Machaon (Y 657)


http://img.over-blog-kiwi.com/1020x7...3_dsc06564.JPG



The system TA called ETBF in french is made by ECA group. Here what they look like.



https://i.skyrock.net/5955/52595955/...6_6sYguent.jpg

A new system exist (there is not known photo just a drawing) it should equip the SSBN (retrofit) and new SSN (Suffren class)



https://i.skyrock.net/5955/52595955/...2_sNVWSkXA.jpg


https://encrypted-tbn0.gstatic.com/i...szE13oRLl0EqGk

I didn't know about this system, however, I have a correction to add, after some quick check, in that it seems the ETBF isn't a towed sonar array, but a towed radio antenna, which is also mounted on other French-made boats.

Source: https://envelopmer.blogspot.com/2014...haeton-et.html


EDIT: second correction, it might be that the system can work with multiple kind of towed antennas, but I have issues finding clear sources saying it does it, most detailed sources talk about ETBF being for a VLF radio antenna but I guess it could also be used for a towed array sonar.

Thanks a lot for that. So to clarify, currently French SSBNs use clip on style towed arrays?

I honestly have no idea. This could be the system used, carrying the towed array at the same time as the radio, or it could be something else entirely.

The Suffren has a towed sismic & sonar linear Flute acoustic antenna ETBF

ETBF: Ecoute Très Basse Fréquence (Listen at Very Low Frequency): 10 to 100 Hz

Range Detection: + 100 km:salute:

So far yes, the reel system take a lot of space especially on the SSN (the Amethyste class is still the smaller nuclear attack sub in the world) and it's less complicated to have a clip-on and it less hole in the hull.



For the Suffren SSN I don't known maybe they have an ECA TA deploying/retrieving system but those who known will not say a word.

Yeah, I just asked around and was confirmed (as well as confirmed that it isn't in any way confidential, the whole process being done in a visible way outside the port) that the towed array on the French SSN and SSBN are just clipped on and dropped when in proximity of the home base. Simple, fail-safe system that reduces the risks of technical failures. Plus, neither the SSBN (for obvious reasons) nor the SSN are sprinters, so less situations where they'd need to reel the array in to avoid breaking it.


For Suffren, I wonder (personal guess, I'm definitely not going to ask anything about it) whether it could be possible to shape the pump-jet in a way that would allow storage of the TA there, or maybe on the sides.


Now, here's on a specialized blog some interesting information (in French): https://lefauteuildecolbert.blogspot...ositif-de.html


One of the SSBN, Le Tonnant experimented a towed array retrieval system, but the nature of the mission of the boomer led to the conclusion that it wasn't really worth it. In a recent book about French SSN, there's a picture of early plans that involves a deployment system:


https://2.bp.blogspot.com/-__0OO9KLn...%2B-%2BALR.jpg


Though, as you can very likely guess, that image isn't in any way representative of the actual submarine (no pump-jet, the screw being shown - which immediately excludes this picture from being about the real thing - and of course the presence of an array support near the control bars which isn't in the boat inaugurated a few days ago), but it seems to show that it was envisioned. It might also be a CGI of a Barracuda variant, like the one successfully sold to Australia or a possible candidate for the Dutch Navy.


Other option to consider: the Suffren is designed to receive an optional SF minisubmarine hangar behind the tower, so maybe there could be a modular towed array system to be mounted there too? Though the technology is mastered already.

SSBNs are big boats, they should have all the space, I mean we place towed on all nuclear boats and some conventional boats (Ladas) while offering it for Kilos.


So French SSBNs not having the towed seems very weird.