Swedish Navy wins first victory since 1790!

Guden Oden

Senior Member
Legend
The "victory" was scored in military exercises involving the US navy versus the ultra-quiet swedish diesel-electric sub Gotland, where the sub has now successfully eluded capture for two months (out of a full year of planned exercises). :)

Gotland employs an advanced and basically vibration-free stirling engine fuelled by diesel and liquid oxygen to generate power in submerged mode, and this gives the boat very long stamina under water. Unlike conventional diesel-electric subs, it does not have to rely on battery power and air stored in tanks; it can generate new fresh oxygen like a nuclear sub and stay under water for weeks at a time, if not more. Also, not being nuclear powered, it means it won't have lots of pumps and turbines spinning, creating lots of noise.

Cool stuffs! Also, lending our submarine for this exercise means lots of US taxpayer dollars finding their way into our coffers, heh heh. Good for our country. :D
 
I always find it pretty amazing that Sweden, which is so anti-war basically, has such a powerfull and big weapons selling industry.....

so you guys dont like war, but some profit is always good? ;)

BTW :: we use swedish anti-boat missiles, Bofors AA guns, some electronics and other stuff....
 
silence said:
I always find it pretty amazing that Sweden, which is so anti-war basically, has such a powerfull and big weapons selling industry.....

so you guys dont like war, but some profit is always good? ;)

BTW :: we use swedish anti-boat missiles, Bofors AA guns, some electronics and other stuff....

Sweden was a serious warmonger in Europe in the past (centuries ago) AFAIK.
 
Not the first "victory" really if you want to call it that. In the mid 90's a Swedish sub humiliated the Royal navy by chasing out a carrier group from its exercise area. (The brits didn't want their carrier sunk so they left the scene).

In 2000:ish a swedish sub not only scored four torpedo hits on an American carrier in an exercise in the mediterranian but it also eluded the rest of the fleet while escaping unnoticed after the kill. Apparantly a first for the Americans. Shortly after that the Australian navy sent a propeller from one of their Swedish built Collins subs to the USA for "repair" in violation of their contract. :)

I'm guessing the analysis has been completed and that it was time to field test their findings.
 
Guden Oden said:
Gotland employs an advanced and basically vibration-free stirling engine fuelled by diesel and liquid oxygen to generate power in submerged mode, and this gives the boat very long stamina under water. Unlike conventional diesel-electric subs, it does not have to rely on battery power and air stored in tanks; it can generate new fresh oxygen like a nuclear sub and stay under water for weeks at a time, if not more.

Interesting. It's burning diesel underwater? How does it vent? Diesel-sniffer as the new sonar? :LOL:
 
silence said:
I always find it pretty amazing that Sweden, which is so anti-war basically, has such a powerfull and big weapons selling industry.....

so you guys dont like war, but some profit is always good? ;)

BTW :: we use swedish anti-boat missiles, Bofors AA guns, some electronics and other stuff....

Well you know what they say... It's always the quiet ones...
 
Don't forget these folks were Vikings and liked to descend in surprise, do their damage, and get out before the locals could organize.

Their longboat just goes underwater now. :LOL:
 
When it comes to subs, I still think that nuclear ones are by far the best idea. I realize that this is a good thing, and will be useful especially for countries like NZ that will not allow any nuclear powered boat in, but you will still have to surface to fill up.

The quality of this sub depends on many things thoug, such as how far can it go with a tank of diesel+oxygen, how fast can it go and so forth. If you can only stay under for long periods when travelling very slow it is not that groovy. Any sub could elude detection btw, it just depends on what they do, the other reports were in other words more compelling to me, i.e. actually "score" a hit and then getting away is better than eluding capture, since all a sub has to do to elude capture is to sit still in silence...

How do these compare to the trident subs in terms of noise/vibration btw?
 
I noticed that noone gave the name of the company building them. Or was it that the forum filters removed the name? :smile: I don't think I could hold a presentation about the company to a English audience, and keep a straight face.
Either way, it's Kockums that builds them. (As if you couldn't find enough phallic symbolism in subs.)

They've also done a few other interesting vessels. Like the stealth corvette Visby, and the minesweeper SAM.
 
Sxotty said:
When it comes to subs, I still think that nuclear ones are by far the best idea. I realize that this is a good thing, and will be useful especially for countries like NZ that will not allow any nuclear powered boat in, but you will still have to surface to fill up.

Well, it's not a replacement for a nuclear hunter/killer sub. Our navy operates in the baltic and kattegat sea which is strictly 'brown-water'. The US Navy is a 'blue-water' navy, which means patrolling the atlantic seabed, following SSBNs and the like. For that you clearly need a nuclear attack sub.

But, for instance, say there's a conflict in Korea again and you have to move in a large surface fleet into the china sea. There, a conventional submarine, especially one that doesn't need to snorkel, can be a formidable asset.

The quality of this sub depends on many things thoug, such as how far can it go with a tank of diesel+oxygen, how fast can it go and so forth. If you can only stay under for long periods when travelling very slow it is not that groovy.

Yes, the cruising speed with the stirling is a few knots, but this actually isn't all that different from a nuclear sub when it is in hostile waters, creeping in on a battlegroup or whatnot. Moving much faster than 5 knots or so you aren't running silent anymore and your own sensors is also working less efficiently. Moving the full 30+ knots everyone in a 40nm radius will hear you loud and clear(cavitation) and you will run basically blind. But it is useful havig speed for tactical evasion and strategic redeployment.

Any sub could elude detection btw, it just depends on what they do, the other reports were in other words more compelling to me, i.e. actually "score" a hit and then getting away is better than eluding capture, since all a sub has to do to elude capture is to sit still in silence...

Heh, pity those pesky brits invented ASDIC in the '30s, otherwise that would've been a stellar tactic! ;)

How do these compare to the trident subs in terms of noise/vibration btw?

Probably quite a bit quiter. All nuclear subs make idle noises because they have to constantly cycle the reactor coolant. If you don't have those to begin with ...well you can insulate/whatever all you want, but you can't go quiter than if you didn't have those to begin with.
 
ASDIC is sonar and sitting quietly defeats it.

MADs (magneticic anomaly detectors) are more effective, but only detect anamolies this means you can pick a spot where one already exists due to iron in the seafloor for example.

Do sterling engines not need cooling? Oh I see they can be passively cooled by the ocean. At least I assume that is how they work. Still I am not sure what is done with exhaust gases, as the heating from diesel would require an exhaust, even if the engine doesn't need one from the pistons.
 
Sxotty said:
ASDIC is sonar and sitting quietly defeats it.

No, ASDIC is _active_ sonar which sends out sonic pulses and detects echoes. Sitting still does not defeat it. Sitting still on the bottom can with certain types of sonar, but medium frequency sonars are capable of detecting contours, albeit at much shorter ranges.

MADs (magneticic anomaly detectors) are more effective, but only detect anamolies this means you can pick a spot where one already exists due to iron in the seafloor for example.

MAD is a nice tool, but it has very short range... you basically have to run over the sub(or within a few hundred metres or so). Better suited for aircraft, but even then you need to have a general idea where the sub is.

Do sterling engines not need cooling? Oh I see they can be passively cooled by the ocean. At least I assume that is how they work. Still I am not sure what is done with exhaust gases, as the heating from diesel would require an exhaust, even if the engine doesn't need one from the pistons.

Stirling runs on heat, not combustion of gasses. You burn something(truly whatever) and dissolve the residues into the water. For instance a completely clean combustion of hydrogen gas and oxygen leaves only water!
 
Right the heat is from Diesel in this case, that is what I was talking about. Sure CO2 is soluble in the ocean, but the gases still have to be vented to the ocean.
 
Moffell said:
In 2000:ish a swedish sub not only scored four torpedo hits on an American carrier in an exercise in the mediterranian but it also eluded the rest of the fleet while escaping unnoticed after the kill. Apparantly a first for the Americans. Shortly after that the Australian navy sent a propeller from one of their Swedish built Collins subs to the USA for "repair" in violation of their contract. :)

I'm guessing the analysis has been completed and that it was time to field test their findings.
While the Collins & Gotland classes are obviously related, the Collins is a different design, enjoys a substantial platforms advantage, larger displacement & greater range in keeping with their different theater of operations roles. All of the Collins class are Australian built, with proprietary ASC IP & joint IP with partner Kockums (now HDW Germany). Tech jointly developed from the project is employed in both classes of subs. Year 2000 sea trials of the broken Collins proved devastating against US/UK groups. So much so that a strategy rethink took place.

The Collins class has been quite the enigma, from initial substantive problems with acoustic performance & weapons platforms, to a stunning package in its upgraded form. So substantial are the boats, that the Collins class are now completely embargoed as an export technology, much to the dissapointment of navies interested in aquiring a large diesel/electric sub. Indeed, this now anulls the entire rationale of developing an independent export capable sub building industry, as the infrastructure/tech will not be exported.

The initial acoustic issues included problematic turbulence from the original spec propeller, which required redesign/recast. This was done by GD Electric Boat, the major supplier of nuclear subs for the US navy & lead to issues of IP & military secrets transfer by one of the Collins partners to the US. The US does enjoy a tech leadership in this field to the extent that the new propellers are themselves classified. This is the only time the US has allowed this level of tech outside the US fleet & required Presidential level authorisation...

The benefits of these new generation DE/AIP subs is that they cost a third of their nuclear counterparts, can be much smaller than comparable nuclear subs (a nuclear power plant takes up a substantial volume), the acoustic signature is dramatically reduced, and the reduced draft means they can get into far shallower waters. Recent Pacific Ocean exercises have seen 3 hunter/hunted Collins class subs sink most of the corresponding US carrier groups & subs. The exercises themselves have become classified. It appears that the upgraded weapons & C&C platforms are upgraded versions (for lower power draw) of the latest Virginia class. This allows for tight integration into the US theatre of war deployment systems & obviates the need for the US to build a non-nuclear sub fleet to supplement their capabilities.

The Canadians picked up the prematurely retired Upholder (now Victory) class from the UK, which were passed up by Australia in favour of the Collins/Kockums deal. The only other non-nuclear contenders are the German 212/214 class (HDW) which are also being built by Greece & S. Korea.
 
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Sxotty said:
Right the heat is from Diesel in this case, that is what I was talking about. Sure CO2 is soluble in the ocean, but the gases still have to be vented to the ocean.

Yep. The dissolution obviously works though. Just don't ask me how it works in detail! :)

http://www.kockums.se/Submarines/aipstirling.html

The main feature of the Kockums air independent propulsion (AIP) system is the use of Stirling engines burning pure oxygen and diesel fuel in a pressurized combustion chamber.

The combustion pressure is higher than the surrounding seawater pressure, thereby allowing the exhaust products, dissolved in seawater, to be discharged overboard without using a compressor.
 
silence said:
I always find it pretty amazing that Sweden, which is so anti-war basically, has such a powerfull and big weapons selling industry.....

so you guys dont like war, but some profit is always good? ;)

That pretty much sums it up. Swedish foreign policy is nothing but hypocracy. On one hand, we're actually doing the right thing, supporting the democratic side and so on. But officially it's a totally different story, we're neutral and we don't sell weapons to countries that are in war. Of course, we've been cooperating with NATO for decades while telling the people to opposite and so far we haven't stopped any weapon shipments to the US or UK for the wars in Iraq and Afghanistan. But then again, with those rules, the Swedish government wouldn't be able to buy weapons itself from Swedish producers either since we have some troops in Afghanistan.
 
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