Swedish Ub-2000 and Viking projects


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11 March 2006
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Before the 'viking' submarine design matured, Sweden was investigating a flatfish design as a configuration for their future submarine requirement. I have little information about the concept or why there may be advantages for a flatfish design (other than operating in shallow waters) I attach an illustration of the design.


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Re: Swedish - Submarine 2000 'flatfish' concept

Sorry to play the resurrection man on this thread, but I've been looking at the illustration, and I'm wondering, was the concept a pure minelayer sub? Or, more likely, was it a minelayer with a alternate/concurrent role as an RPV mothership? I take it that it came out of Kockums?

EDIT: Just had a look at the Kockums Sub brochure. On the two page illustration of future sub concepts at the back of it, there is what appears to be a (poor) side view of the same concept. Also on there is a smaller illustration of a related but more conventional (probably notional) design that is used to illustrate one of their micro-sub operational concepts. Some other interesting concepts there, including what looks like an airdroppable minisub/USV.

Brochure can be found here: http://www.kockums.se/en/products-services/submarines-systems/
Re: Swedish - Submarine 2000 'flatfish' concept

Tried to edit my post again, but ran into some sort of bug. Anyhow, just speculation, but based on the last page of the brochure, the concept designation may have been (or still is) X-2.
Re: Swedish - Submarine 2000 'flatfish' concept

Flatfish concept was connected to design studies for the 'submarine-2000' which wasfor a fully opperational SSK. A less radical solution for the submarine programme was adopted the A26.


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Re: Swedish - Submarine 2000 'flatfish' concept

JAZZ said:
Flatfish concept was connected to design studies for the 'submarine-2000' which wasfor a fully opperational SSK. A less radical solution for the submarine programme was adopted the A26.

Sorry I should have said possible company designation.
Research thread - I have a detailed article pending.

In design terms, in between Gotland and A26. Ub-2000 was much more conceptually advanced, while Viking was much more modest and intended for Swedish-Norwegian-Danish service. Both designs were ill-fated due to politics and now we have the A26...


Kockum's illustration of Ub-2000 deploying its ROV which acted as a mast system and active sonar platform. Note the wide 'flounder' hull form and tiny sail.

Any info that might help with a detailed article would be great :D
Finally got around to writing up the A21 Flounder design here http://www.hisutton.com/Sweden_A21_Flundran_submarine.html. So much ahead of its time but unproven hull shape. Viking was a real step backwards but A26 finally delivers some Ub-2000 concepts.

Research owes much to Fredrick Granholm who sadly passed away in 2017. By contrinuing to post of Swedish sub projects I hope to honor his efforts.

There is now a bit more info on Swedish language sites, maybe my previous round of articles reminded a few people. I hope at least.


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Old 'flatfish' thread: https://www.secretprojects.co.uk/forum/index.php/topic,2254.0.html
Thanks, maybe merge threads?

Done ! ;)

Re designation, not heard the X2 designation before but A21 is standard Swedish designation.
Thanks for that article!

Another interesting Swedish concept which deploys near-term technologies in pioneering ways...

I'm a bit surprised they balked at the oval double hull though - doesn't seem all that more radical than the earlier Oscar or Typhoon hull forms? Of the innovations proposed I would have thought the sonar and propulsion systems would have been considered bigger obstacles.
As I understand it, in around 1990 Kockums were attempting to use computer models to predict hydrodynamics, but the unusual hull form meant that the calculations were taking much too long. So they went the safer route.

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