U-214 SSK problems

[Betasys]

Some more details:
......
-Noise to the low frequences which maybe comes from the propeller and according to Navy;s circles this problem is very serious..for this issue there is a study of the University of Hamburg saying that this problem cannot be solved
.....

"The problem [of high noise levels] cannot be solved" can be interpreted as confirmation of propeller-hull hydrodynamics issue.
Could be that the geometry of the stern, its surfaces and the departure from axial symmetry interacting with propeller positioning make the best possible propeller geometry still unacceptably loud. In this sense the impossibility is to be interpreted as 'given the present hull'.
If so the geometry of the stern would have to be changed radically (!) to find an entirely different path leading to a better solution.

 

[Betasys]

....
If so the geometry of the stern would have to be changed radically (!) to find an entirely different path leading to a better solution.

..If the stern were in fact in need of redesigning that would be a stern reminder of the difficulties of submarine design.
...Sorry I couldn't resist that one. Silly me.

 

[fantasma]

" In this sense the impossibility is to be interpreted as 'given the present hull'.
If so the geometry of the stern would have to be changed radically (!) to find an entirely different path leading to a better solution.

I guess you are right..in order to meet fully operational requirements and fulfill the initial standards on paper of the U214 it has to be redesigned..lucky Greek Navy..

 

[gf0012-aust]

..If the stern were in fact in need of redesigning that would be a stern reminder of the difficulties of submarine design.
...Sorry I couldn't resist that one. Silly me.

Its almost impossible to speculate what is the issue here.

noise and vibration is one of those things that can be transmitted under specific conditions.

it could be any number of things:

• cavitation issues at specific speeds
• prop bleed at certain speeds
• acoustic swirl aft of the tower (highly unlikely)
• thruster shape
• inapprop dampening/rafting
• bearing alignment (highly unlikely)

I'd be tempted to wait and see what comes out (if any) - and I must say that I'm quite dubious about what the actual problems are, due to the way that they've been discussed and promoted in the popular press.

 

[Betasys]

Its almost impossible to speculate what is the issue here.

noise and vibration is one of those things that can be transmitted under specific conditions.

it could be any number of things:

• cavitation issues at specific speeds
• prop bleed at certain speeds
• acoustic swirl aft of the tower (highly unlikely)
• thruster shape
• inapprop dampening/rafting
• bearing alignment (highly unlikely)

I'd be tempted to wait and see what comes out (if any) - and I must say that I'm quite dubious about what the actual problems are, due to the way that they've been discussed and promoted in the popular press.

My speculation is based on and attempts to integrate two 'known' elements.
1. HDW is experimenting different propellers.
2. 'The problem can't be solved'

If these were true then the problem might be hull-propeller interaction. You reckon that plausible assuming the two accurate?

 

[gf0012-aust]

My speculation is based on and attempts to integrate two 'known' elements.
1. HDW is experimenting different propellers.
2. 'The problem can't be solved'

If these were true then the problem might be hull-propeller interaction. You reckon that plausible assuming the two accurate?

superficially - and I stress superficially, that points to cavitation issues - it can also point to fluid dynamics noise generation issues between the stern and whatever propeller is in place (ie shrouded, unshrouded, blade shape, bleed at specific speeds etc....

theres no such thing as a problem that can't be solved.....

one of the significant disadvantages of smaller subs is that they act like a transducer - one acoustic stuff up and the whole world will hear a sailor fart....

 

[orko_8]

Somehow I have the feeling that a portion of the vibration and/or noise problems may have roots in HDW's horizontal rudder design.

In Type 209 class, HDW used assymetrical "spoon" like horizontal rudders. These rudders are stored inside the hull and are not extended above certain speeds and certain deflection angles. In Type 212 class (and also Dolphin), HDW switched to another design solution in which rudders are mounted on either side of the sail, which is said to increase noise generation. As far as I know, HDW than chose to mount the rudders in the bow section of the boat in Type 214, like most conventional submarine designs. Maybe switching from the proven rudder design of Type 209 family did not result as planned in terms of noise signature and stability.

Just 2 cents...

 

[gf0012-aust]

Somehow I have the feeling that a portion of the vibration and/or noise problems may have roots in HDW's horizontal rudder design.

In Type 209 class, HDW used assymetrical "spoon" like horizontal rudders. These rudders are stored inside the hull and are not extended above certain speeds and certain deflection angles. In Type 212 class (and also Dolphin), HDW switched to another design solution in which rudders are mounted on either side of the sail, which is said to increase noise generation. As far as I know, HDW than chose to mount the rudders in the bow section of the boat in Type 214, like most conventional submarine designs. Maybe switching from the proven rudder design of Type 209 family did not result as planned in terms of noise signature and stability.

Just 2 cents...

Its possible, but that should have been picked up in tank testing (apart from the "nonlive" fluid dynamics simulation)

 

[SATAN]

Its possible, but that should have been picked up in tank testing (apart from the "nonlive" fluid dynamics simulation)

Anyone know if South Korea is having any problems of the sort with their U-214s ?

 

[orko_8]

Anyone know if South Korea is having any problems of the sort with their U-214s ?

http://times.hankooki.com/lpage/nation/200612/kt2006120620420211990.htm

According to the above news, Korea is preparing to give orders for 6 more Type 214 submarines, let alone having problems in the first boat.

Hellenic Navy's first type 214 boat, the Papanikolis was built in HDW shipyards, Kiel (the remainder to be built in Hellenic Shipyards, Skaramanga), while all 3 Korean boats are building in Hyundai Heavy Industries, Ulsan.

By the way, this is from navyleague.org

Greece Refuses Delivery Of First Type-214 Submarine

By AMI INTERNATIONAL INC.

The Greek Ministry of Defense and Hellenic Navy have refused to accept the first Katsonis-class (Type 214) submarine being built by Howaldtswerke Deutsche Werft (HDW) in Germany, citing a variety of concerns. Sources indicate that the Hellenic Navy has identified the following as among the continuing problems with the submarine, dubbed Papanikolis:

* The submarine is reportedly highly unstable while surfaced;
* The air-independent propulsion system has lower output power than specified; the unit must be shut down after several hours of sailing due to higher than normal operating temperatures;
* Increased propeller cavitations;
* Attack periscope vibrates at speeds greater than 3 knots;
* Seawater leakage into hydraulic systems;
* Problems with the proper function of the flank arrays.

Hellenic Navy sources indicate that the sea service will not accept delivery until, at a minimum, the stability problem is resolved. The delivery of unit one is now more than 18 months behind schedule and the second unit, being built at Greece’s Hellenic Shipyards, which was acquired by HDW in 2001, is expected to be launched by the end of the year. Four Katsonis-class submarines in all have been ordered, with all but the first being built at Hellenic Shipyards.

http://www.navyleague.org/sea_power/dec06-52.php

 

[SATAN]

http://times.hankooki.com/lpage/nation/200612/kt2006120620420211990.htm

According to the above news, Korea is preparing to give orders for 6 more Type 214 submarines, let alone having problems in the first boat.

Hellenic Navy's first type 214 boat, the Papanikolis was built in HDW shipyards, Kiel (the remainder to be built in Hellenic Shipyards, Skaramanga), while all 3 Korean boats are building in Hyundai Heavy Industries, Ulsan.

By the way, this is from navyleague.org


http://www.navyleague.org/sea_power/dec06-52.php

That is impressive. 9 U214 SSKs for the S.Korean navy?. Any idea when all 3 will be built by Hyundai? I know Samsung manufactures S.Korea's F-16s under license from Lockheed Martin.

 

[orko_8]

That is impressive. 9 U214 SSKs for the S.Korean navy?. Any idea when all 3 will be built by Hyundai? I know Samsung manufactures S.Korea's F-16s under license from Lockheed Martin.

The first 3 are planned to enter service by 2010 IIRC.

 

[contedicavour]

Reassuring. If S. Korea has no problems with their U214 then there are no flaws with the programme in itself... but only with one specific unit for the Greek Navy. Still a very strange story. Has HDW communicated how much time they need to correct the issues that the Greek Navy has flagged ?

cheers

 

[orko_8]

Has HDW communicated how much time they need to correct the issues that the Greek Navy has flagged ?

cheers

I remember reading somewhere a timetable ranging from 12 to 18 months, but take this information with a grain of salt, since the issue had long become a much speculative one lately.

 

[contedicavour]

I remember reading somewhere a timetable ranging from 12 to 18 months, but take this information with a grain of salt, since the issue had long become a much speculative one lately.

Ouch that's a long time... with the first U214 in service in 2008, the whole class of 4 subs won't be ready before 2012. By then only 4 U209s will remain in service.

cheers

 

[slapshot]

Kinda off topic but I justs wanted to comment on one of contedicavour postes here about France not being successful in the export market for subs. The Daphne class of French Diesel Electric subs in the 60's was a very succesfull design and was exported to Portugal, South Africa and Spain I believe and they where very well regarded by the navied that purchased them. They gave the Brittish Oberion class a run for there money in the export market
Cheers

 

[contedicavour]

Kinda off topic but I justs wanted to comment on one of contedicavour postes here about France not being successful in the export market for subs. The Daphne class of French Diesel Electric subs in the 60's was a very succesfull design and was exported to Portugal, South Africa and Spain I believe and they where very well regarded by the navied that purchased them. They gave the Brittish Oberion class a run for there money in the export market
Cheers

Fully agree with you, my comment is more about the last few years, and actually related to the entire French defence industry. The Scorpene (though Franco-spanish not purely French) sold to Malaysia, Chile and India are a big success, though still inferior to the numbers of U209/U212/type800/U214 sold by HDW. The Lafayettes sold to Saudi, Singapore, Taiwan are also a big sucess. It's outside of the naval context that it's been more difficult lately for the French : witness the Rafale or the Leclerc MBT's international career (respectively 0 and 1 customer). Though only partly French, Eurocopter has been much more successful.
In summary : international cooperation is very useful

cheers

 

[orko_8]

...speaking of Type 214; Brazil Navy today announced its selection of Type 214 submarines and denounced plans for nuclear powered attack submarine, according to Reuters.

Together wth S Korea's 6 additional Type 214 orders, this is a real bomb into the market I think

Let's what will come out of HN's issues?

 

[fantasma]

From a magazine there was an article about the problems concerning the H.N 214 and on the head of the topic saying that the same problems except the stability problems while sailing in certain sea conditions are facing and the australians 214 class Collins..if anybody knows about the australian 214 case may send something on that

 

[gf0012-aust]

From a magazine there was an article about the problems concerning the H.N 214 and on the head of the topic saying that the same problems except the stability problems while sailing in certain sea conditions are facing and the australians 214 class Collins..if anybody knows about the australian 214 case may send something on that

well, australia doesn't use the 214. the Collins is a Type 471 based on a swedish design. It was chosen over a modified 3000 tonne "maxi version" of the 209.

australia also uses a St Andrews Cross tailplane config - and has never had handling problems. the St Andrews Cross was the first integrated with a "non nuke" joystick controlled steering/plane control.

It's handling is regarded as impeccable and highly responsive - and is semi FBW.

Your article is wrong - certainly with respect to Collins comparisons.