;)
Posted on 10/03/2005 7:51:25 AM PDT by anguish
Swedish submarine stays hidden to Americans
Despite two months of searching, the American navy still have problems locating the Swedish submarine 'Gotland' in a series of cat-and-mouse games in American waters. Now also the Canadian and Australian navies will practice finding Swedish subs. This was recently given the green light by the Swedish government according to 'Blekinge Läns Tidning' [Swedish newspaper] The US has since this summer rented 'HMS Gotland' with two crews. The submarine is to stay for a year, but the contract can be extended because of the problems in locating it. This, in turn, pleasures Kockums [the shipyard building these subs] in Karlskrona. |
As a sidenote, this story began when a Swedish sub (same class, maybe the same ship) on its way to the Mediterranean met up to practice with a LA-class sub in the Atlantic a couple of years ago. The American response, at that time, was that the sub "came and disappeared like a ghost". In the Med it also made life miserable for the crew of a French nuclear sub.
Links:
Gotland Class submarine (Kockums)
Gotland Class submarine (Naval-technology.com)
PING
;)
It is a small diesel boat - non nuclear so it has to surface on a regular basis to charge its batteries. I don't think the AIP drive charges its batteries to stay down however that would be pretty impressive.
From the hull design it looks pretty impressive but all diesel boats once submerged are very quiet but limited range - as opposed to a nuc boat that can go deep and around the world without surfacing.
Diesels have always been quiet and difficult when submerged to find - sadly we (US Navy) got rid of all our active diesle boats for nuc as a military weapon.
Modern D-E submarines (especially those with AIP) can be bl@@dy murder to find. Particularly in littoral waters. They can have lower acoustic signatures than nuke boats, and in littoral environments can be a viable threat. Obviously this requires a competent crew, and most nations with DE subs either do not have the most modern versions or lack hgihly-trained crews. However were we to face a foe nation that had a selection of modern D-E boats, and had actually put the effort into training top-notch crews, and they decided to delve solely into littoral waters .....well, those D-E boats would become a major pain. Not saying they would win, but would definitely cause a lot of headaches (and might even draw blood).
I don't think the AIP drive charges its batteries to stay down however that would be pretty impressive.Two weeks (at 5 knots) is the offical figure on how long it can stay submerged.
Saw Gotland exhibit at a recent Navy expo and was extremely impressed...small and quiet.
non sequitur
Not Sterling engines, Stirling Air Independent Propulsion, using LOX (hold the cream cheese)
Got Land?
For trans-ocean trips a nuke sub would be hugely advantageous, however if all a nation needed to do is defend its shores then a D-E boat is more than sufficient. And with AIP they do not need to regularly surface .....they can stay under for around 2 weeks.
From the website for the Kockums Stirling AIP system:Instead of a number of days, a Stirling AIP submarine can extend the time submerged to weeks and thus outperform any other conventional submarine with regard to that key capability - submerged endurance.
In littoral waters, the ability to stay submerged for a couple of weeks is a pretty potent ability. Non-AIP subs have to pop up every couple of days, as compared to a couple of weeks for AIP D-E boats.
Hmmmmm..... Like an island off the coast of China, perhaps?
And on the surface, they sound like any other boat. If they don't transmit anything on the surface, they're extremely hard to find.
PROPULSION SYSTEMS
The submarine is equipped with two MTU diesel engines and two Kockums V4-275R Stirling Air Independent Propulsion (AIP) units. The Stirling engines are mounted in elastic, soundproof modules and each provide up to 75kW. The submarine has the capacity for two weeks of air independent propulsion at a speed of 5 knots without snorting. The AIP uses liquid oxygen and diesel fuel in a controlled inert (helium) environment. The AIP liquid oxygen tanks are located on the deck below the engines. The propulsion system provides a speed of 11 knots surfaced and 20 knots dived.
Fantastic for coastal defense. Terrible for strategic capability. The AIP systems are obviously reliant on a home port or tenders to refuel their LOX.
Walther cycle?
Oh. Not Walther cycle...
Yet, I was under the impression we still could manufacture diesel boats. Taiwan is supposed to buy some from us, but it is being held up in their legislature. (Evidently Taiwan doesn't feel it has to maintain its capability. This belief is based on the assumption that we will defend Taiwan.)
Bout time we got credit 4 sumtin side the screw prop and dynomite!~
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