SUBSIM Radio Room Forums - Air-Independent Propulsion

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Air-Independent Propulsion

I'm curious about the propulsion mentioned in this article:

http://www.thenewanatolian.com/tna-21294.html

"...the first prototypes were constructed by the Germans during the World War II but they failed to experiment and use them before the war ended..."

"...the system has become common since the '90s..."

Anyone know what this is talking about? Very interesting!

LOL that looked like a question mark icon. Oops!

Thanks for the links, heading over now to read up.

http://www.chinfo.navy.mil/navpalib/...-XVIIB-sub.gif
Partially dismantled Walter Type XVIIB U-1406 up on the stocks shortly after the end of World War II.

http://www.maniadekit.com.br/images/Fotos/RVA5019.JPG
Modern Type U212a

more:
http://www.chinfo.navy.mil/navpalib/...propulsion.htm

regards

Quote:

Originally Posted by Smaragdadler

Yep - looks like the Germans are using old tech from WWII - they just spruced up the boat a bit even though it was built 60 years ago! :D

Na,na! We have spruced it DOWN!!! Whe don't whant do rule tze world ägain, thiz time it has jüst önly 400PS not 5000! For real, man.

Quote:

...he fielded a fully functional - if troublesome - 5,000-horsepower AIP system in 1945, the maximum power output of current AIP installations is typically on the order of 400 horsepower (300 kilowatts)...

:arrgh!:

I like the U212. Looks nice and just nice enough for a small SubSim crew :D

Turks with subs:hmm:

Quote:

The Turkish Naval Forces has recently initiated a process to purchase six submarines with the highest technology possible.

The submarines are to include an "air-independent propulsion" system and will be able to roam under water for 50 days and will be difficult to detect due to stealth technology, which currently grants several military vehicles ghostlike mobility.

Stealth subs at that:hmm:

This should prove intresting.

Quote:

Originally Posted by U-533

Turks with subs:hmm:

Quote:

Stealth subs at that:hmm:

This should prove intresting.

As we all know that kind of is the point regarding the building of submarines, that is to make them stealthy. :ping:

I don't know why America don't develop its own AIP... Even Russia, which is relatively poor after her dissolution, got her AIP technology ready. It seems that America is relying on her sucking (noisy + expensive) Los Angels Class, which can be a huge DISADVANTAGE when she wants to use it in shallow seas. China might get one, by buying one Russian sub (just like Kilo)

I thought that the virginia class was designed for more 'littoral' work. At least, thats what i read when having a look into it recently

The new virginias are good but they are still large submarines thier draft alone wont allow them into realy shallow waters where say a kilo can go or a 212 which puts the virginia at a disadvantage but only a slight one.

Despite being very quite the nukes have always been alot louder than a conventional submarine so in shallow waters with a conventional your basicaly not existing at slow speeds.

i have no doubt that the type 212 is alot quieter than a virginia.

Quote:

Originally Posted by Kapitan

i have no doubt that the type 212 is alot quieter than a virginia.

The 212 at the moment, is the quietest submarine in the world. So no doubt it's quieter than the Virginia's. :yep:

Well, that article isn't real informative. And the "specifications" listed are highly misleading (50 days "underwater" because you're running with a snorkel at 15 meters) .

AIP's, if I remember, are just a Sterling engine and compressed oxygen. The system is "air-independent" like the Space Shuttle is air-independent -- until it's next refueling. It is a good idea if you used your nuclear reactor to generate the oxygen, then shutdown and run on the Sterling. The pump noise would disappear during the 6 or 7 days the oxygen supply lasts. These AIP's are diesel boats. Once the AIP runs out of oxygen it's just a regular old diesel boat. Much cheaper to build than a nuke. Quiet when it's running on batteries, loud as hell when it's time to recharge.

They're a good idea if you're going with a zerg rush. Which is pretty much what America is going to have to re-tool to defend against. I personally think pebble-bed reactors and these AIP's would make for one quiet, small boat.

plus, it has to refuel very often, meaning it can't do littorial work for very long. Virginia can stay there for ~15 years, food supplies limiting it only.

Quote:

Originally Posted by ASWnut101

plus, it has to refuel very often, meaning it can't do littorial work for very long. Virginia can stay there for ~15 years, food supplies limiting it only.

The next step after AIP is clearly FIP - Food-Independent Personnel system :rotfl:

Quote:

Originally Posted by tycho102

AIP's, if I remember, are just a Sterling engine and compressed oxygen...

Some AIP systems are using fuel cells now instead, but the idea is still the same; range is still limited and recharging is still noisy as all get out.

Quote:

Originally Posted by peterloo

I don't know why America don't develop its own AIP...

Why would they? As we've mentioned AIP range is limited. Most things the U.S. wants to do with its subs take place thousands of miles away, closer to political hotspots. This is okay if you want to establish forward bases or refuel along the way, but I think it's more cost-effective to operate boats that have the endurance to get themselves there. Going nuclear also allows for bigger, faster subs, with bigger armament. Of course, the new SSNs are not as quiet as diesel boats, that's for sure. But by no means does that mean they are loud.

I believe AIP can be a real silver bullet for defending home coasts. They are brilliant for smaller nations with lots of neighbours and lots of coastal interests, e.g. Sweden. They can send their subs to go splash around for a bit longer - and a bit quieter - then they would without AIP.

taken from my link above:

Quote:

...the conventional diesel-electric plant of the U 212 class described above is rated at over 3,000 horsepower, and a typical nuclear submarine propulsion plant produces over 20,000. Since the power required to propel a submerged body varies with the cube of its velocity, it should be apparent that at least for the near future, AIP will be valuable primarily as a low-speed, long-endurance adjunct to the under- water performance of conventional submarines. There is little short-term prospect for AIP to become a primary, full-performance alternative to either diesel or nuclear power. Even the phrase "closed cycle" is something of a misnomer, because except for fuel cells, all AIP alternatives require ejecting exhaust gases overboard, which limits both depth capability and stealth.

However, this is not to minimize the dangerous potential for AIP submarines to complicate seriously both coastal defense and assured access to littoral regions. If their distinctive characteristics are exploited by skillful operators, AIP submarines can be used to telling effect for both short- and medium-range missions. AIP dramatically expands the tactical "trade-space" for diesel-electric submarines. If conditions permit, they can transit rapidly on the surface with-out unduly expending the wherewithal for superior underwater performance. Submerged, they can opt for a long, slow, silent patrol that keeps their batteries fully charged and thus capable of powering speed bursts of significant duration. And by carefully husbanding their resources, they can revert again to slow-speed operation and repeat the cycle several times over weeks of submergence. Moreover, AIP technology is evolving rapidly, and some experts predict, for example, that the power output of a typical fuel cell module could well double or triple in the next several years, allowing an even more advantageous trade-off between underwater speed and endurance.

Their tactical flexibility, their small size, their inherent stealth - and the novel operational paradigms AIP submarines introduce to undersea warfare - will make these new boats a dangerous threat to submariners accustomed to nuclear- or conventionally diesel-powered adversaries. The Submarine Force needs to understand this threat - where it's been, where it's going, what it means, and how to counter it.

Quote:

Originally Posted by ASWnut101

plus, it has to refuel very often, meaning it can't do littorial work for very long. Virginia can stay there for ~15 years, food supplies limiting it only.

Actually, Virginia was designed to go without nuclear refueling for the duration of the 33 year career planned for her, so if one eliminates the necessity of food, she could theoretically stay on station for that duration.