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ShinyBaldy
08-01-2005, 05:20 PM
Aside from the German type 212s... I'll say it seems like the Japanese Oyashio class seems to be really unconventional in design.

Anyone know more?

ShinyBaldy
08-01-2005, 05:20 PM
Aside from the German type 212s... I'll say it seems like the Japanese Oyashio class seems to be really unconventional in design.

Anyone know more?

Celeon999
08-02-2005, 03:43 AM
Oyashio class (http://www.globalsecurity.org/military/world/japan/oyashio.htm)

I think the hull isnt so uncoventional at all.


Strange is that it is so slow.

Only 12 knots surfaced and 20 knots submerged ?

I would think that shape of the hull was designed in that way to improve its hydrodynamic performance. But why is it so slow then ?

And as far as i know its hull is still made of conventinal magnetic steel.

Anyone knows more about how quiet it is ?

ShinyBaldy
08-02-2005, 09:30 AM
I'll assume any improvements in the hull would only extend the endurance of the system...

it isn't slow for a diesel - most diesels are 20knots max submerged... any higher and the system can simply not provide enough power.. realize that drag increases expotentially as speed increases... the power output difference between 20knots and 21 is huge...

which is what's so amazing about nuclear power

WilhelmSchulz.-
08-02-2005, 11:19 AM
Most subs now are bult for underwater paformince, just because its slow on the surface dosint mean its slow underwater. Renember the speeds for the Type XXI U-Boat?

ShinyBaldy
08-02-2005, 03:04 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WilhelmSchulz.-:
Most subs now are bult for underwater paformince, just because its slow on the surface dosint mean its slow underwater. Renember the speeds for the Type XXI U-Boat? </div></BLOCKQUOTE>

I think Celeon999 was wondering why 20 knots was the max speed for even submerged... since the Type 212 and pretty much all diesel subs since the 1940s were hitting 20knots max speed.

paulhager
08-03-2005, 08:27 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ShinyBaldy:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WilhelmSchulz.-:
Most subs now are bult for underwater paformince, just because its slow on the surface dosint mean its slow underwater. Renember the speeds for the Type XXI U-Boat? </div></BLOCKQUOTE>

I think Celeon999 was wondering why 20 knots was the max speed for even submerged... since the Type 212 and pretty much all diesel subs since the 1940s were hitting 20knots max speed. </div></BLOCKQUOTE>

Obviously drag is an issue. The real limit is imposed by cavitation because it generates so much noise. The top "tactical speed" is around 25kts. The old Soviet Alfa class attack sub was probably the fastest sub ever built. Supposedly, when one of those babies was cranked up to full speed it could be heard from one side of the Atlantic to the other.

So, a submarine that operates at a max of 20kts submerged isn't really at a disadvantage. In fact, diesel-electrics, when not snorkeling are quieter than nukes. Nukes, you see, can't get around the necessity to cool the reactor core (so far as I know, passive cooling isn't feasible with current technology). Cooling the core means running the pumps and that generates noise. Quieting nukes is therefore a considerable challenge.

The future of non-nuclear submarines is
Air Independent Propulsion (http://www.chinfo.navy.mil/navpalib/cno/n87/usw/issue_13/propulsion.htm) (AIP). The Swedish Stirling-engine system was profiled on one of the Discovery Channels (The Military Channel?) in a program about the new Virginia Class attack subs. Of note was the fact that women serve on Swedish subs. A great moment in the show was when a female officer - an archetypal nordic blonde - was being interviewed (in the sub) and one of her male crewmates walked through a hatch wearing only a tee-shirt and thong underwear. The woman took absolutely no notice.

But, I digress...

The ultimate non-nuclear propulsion system would probably be fuel cells. As noted in the link, the biggest problem is hydrogen storage. Metal hydrides were proposed decades ago as the way to store hydrogen for use as a portable fuel. Aside from safety benefits, hydrides actually store more hydrogen by volume than can be stored by liquifying it. There is, however, a weight penalty -- metal hydrids are heavy.

Celeon999
08-03-2005, 11:39 AM
Another thing :

There is a rumor around that type 212 has no active sonar anymore. Anyone knows if this is true ?

Another rumor says it has a special navigation system that uses the gravitational field of the earth to determine its position.

That means that it doesnt need to surface and use GPS anymore.

WilhelmSchulz.-
08-03-2005, 03:50 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Celeon999:
Another thing :

There is a rumor around that type 212 has no active sonar anymore. Anyone knows if this is true ?

Another rumor says it has a special navigation system that uses the gravitational field of the earth to determine its position.

That means that it doesnt need to surface and use GPS anymore. </div></BLOCKQUOTE>It could be true. Subs are bulit for stelth and the active sonar defets this porpus. Therefore sub comanders rarley "yankey"search because it would give away there position and open them to atack. Now there some sercumstances where skippers will yankey search. But like I said it is rareley used.

Dan_662
08-21-2005, 02:21 PM
I wonder if maybe the subs maximum speed is really as advertised, and also note that the Japansese submarine force has no long range enemy so more economical speed is perhaps what the sub was designed with in mind. Just a guess. That is all.

gabriel_cd
08-21-2005, 07:59 PM
In my opinion, most capable = most silent, we all know that a submarine's key weapon is stealth, especially with today's advanced torpedoes. That being said, my entry is: RUSSIAN KILO CLASS (TYPE 636).

"The Type 636 submarine is considered to be to be one of the quietest diesel submarines in the world. It is said to be capable of detecting an enemy submarine at a range three to four times greater than it can be detected itself."

WilhelmSchulz.-
08-21-2005, 08:24 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by gabriel_cd:
In my opinion, most capable = most silent, we all know that a submarine's key weapon is stealth, especially with today's advanced torpedoes. That being said, my entry is: RUSSIAN KILO CLASS (TYPE 636).

"The Type 636 submarine is considered to be to be one of the quietest diesel submarines in the world. It is said to be capable of detecting an enemy submarine at a range three to four times greater than it can be detected itself." </div></BLOCKQUOTE>The KILO sub is Soviet made and Soviet sonar is truly lacking. Not intill the AKULA class subs came out did Russia have a "true" digital sonar. In my opion the quietest sub is the Seawolf and new Virgina class subs. True if u get close enough they could be givin away by reactor noises, but alied sonar is so good that they could move out of the way before the sub gets that close. http://forums.ubi.com/images/smilies/25.gif Read Tom Clancy's SSN and youl quickly dismis the idea of the KILO being the quiteest sub in the world.

gabriel_cd
08-21-2005, 09:56 PM
'allied sonar'? http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

The Type 636 is the newest Kilo. My money is on Russian technology and their ability to keep it secret...

WilhelmSchulz.-
08-22-2005, 03:25 AM
Hey I got my head in the 80's right now.

paulhager
08-23-2005, 07:13 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by gabriel_cd:
'allied sonar'? http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

The Type 636 is the newest Kilo. My money is on Russian technology and their ability to keep it secret... </div></BLOCKQUOTE>

With all due respect, in the conventional department, my money is on the Germans and Swedes. I also just stumbled on this item (http://www.prosieben.de/lifestyle_magazine/www/themenarchiv/themen_1_n/13595/) about a German-designed 800 kph supercavitating GUIDED torpedo called the "Barracuda".

Future submarines will require not only stealth but also speed via supercavitation. The only way to have the sustained power to propel a sub at supercavitating speeds for extended periods is to use nuclear. Obviously advanced reactors would be needed - something like a plasma core reactor. The only problem I see would be the heat signature: a plasma core would run at 50K degrees kelvin.

Celeon999
08-23-2005, 09:18 AM
Ahh now it has a name. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Last time i heard of it it had just a project number.

Barracuda ? http://forums.ubi.com/groupee_common/emoticons/icon_confused.gif

I had hoped for a more innovative name. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Well at least its more innovative than "Shkval" http://forums.ubi.com/images/smilies/35.gif

paulhager
08-23-2005, 09:34 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by paulhager:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by gabriel_cd:
'allied sonar'? http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

The Type 636 is the newest Kilo. My money is on Russian technology and their ability to keep it secret... </div></BLOCKQUOTE>

With all due respect, in the conventional department, my money is on the Germans and Swedes. I also just stumbled on this item (http://www.prosieben.de/lifestyle_magazine/www/themenarchiv/themen_1_n/13595/) about a German-designed 800 kph supercavitating GUIDED torpedo called the "Barracuda".

Future submarines will require not only stealth but also speed via supercavitation. The only way to have the sustained power to propel a sub at supercavitating speeds for extended periods is to use nuclear. Obviously advanced reactors would be needed - something like a plasma core reactor. The only problem I see would be the heat signature: a plasma core would run at 50K degrees kelvin. </div></BLOCKQUOTE>

ADDENDUM: if you follow the link to the main site, there are 4 pdf's of the full magazine article. Check out page 32 in the 4th file. There is a reference to SH3!

Celeon999
08-23-2005, 10:10 AM
How much renown for an "barracuda" ?


http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

julien673
08-23-2005, 10:19 PM
The BEST sub ever is from the Canada


---&gt; ok i know the exit http://forums.ubi.com/images/smilies/1072.gif

Vincent555
08-24-2005, 03:40 AM
How about the english,australian and dutch diesel subs? I read somewhere that the dutch "walrus" class is one of the most silent diesel subs around. Is this true?

GunFury
08-24-2005, 04:38 AM
How about the UK Upholder class?

Hawkmoon230
08-24-2005, 06:32 AM
Hmm.........supercavitating.....

Rumour has it that the Russians were testing torps using this idea in the mid ninties, the main draw back for a sub is noise the proposion has to be some type of rocket motor which combined with the cavitation (a subs worst enemy even with screws) would give away the subs position. So a sub doing it well first off we can't biuld a usable rocket powered aircraft so imagine how much fuel a sub would need and don't start talking about plasma becaues a trail of ionised water leading right up your stern is the last thing a bout commander would want.

The most likly next major advance in sub tech' will be some type of induction drive where water can be moved through 'tube' via a 'non-mechanical system' this would allow far higher speeds to be reached with out the limitations of screws, the biggest being cavitation.

Just my 2 cents

paulhager
08-24-2005, 06:45 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Celeon999:
How much renown for an "barracuda" ?


http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif </div></BLOCKQUOTE>

Around 2,000,000 I think... probably several billion for a supercavitating sub. Naturally the sub would have to have anti-torp gatling guns firing 20mm supercavitating depleted uranium rounds but those would be standard - no extra charge. I suspect underwater lasers would cost extra...

Blabaer
08-24-2005, 07:52 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WilhelmSchulz.-:
True if u get close enough they could be givin away by reactor noises, but alied sonar is so good that they could move out of the way before the sub gets that close. http://forums.ubi.com/images/smilies/25.gif Read Tom Clancy's SSN and youl quickly dismis the idea of the KILO being the quiteest sub in the world. </div></BLOCKQUOTE>

No please DON'T read that craap...bought it, read it and cried as I dumped the book in the trash!!! (I love Clansy but when you read the book and they get to target sierra nr100 something in the end they have sunk around 50 ships with thae same sub got detekted once and restocked once.....that was real and utter abomination....)

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">It could be true. Subs are bulit for stelth and the active sonar defets this porpus. Therefore sub comanders rarley "yankey"search because it would give away there position and open them to atack.-WilhelmSchulz. </div></BLOCKQUOTE>

only problem there lies in if the other side has you on passive sonar and all you know is that a torpedo is incoming....you just might want to shoot back at where the other sub truly is...

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Nukes, you see, can't get around the necessity to cool the reactor core (so far as I know, passive cooling isn't feasible with current technology). Cooling the core means running the pumps and that generates noise.-paulhager </div></BLOCKQUOTE>

I think the cooling pumps can be eliminated with a naturalflow liquidsodium reactor...don't know the proper name still gives flow and turbine noise though....

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">How about the english,australian and dutch diesel subs?-Vincent555 </div></BLOCKQUOTE>
Seem to remember something aboute the Aussies "just" buying 3 Swedish AIP subs...but cant find any information where I'm looking....:/

http://www.****ums.de/Submarines/gotland.html

walterlzw
08-24-2005, 11:43 AM
I don't know but I like the Russian Kilo class subs. It is very quiet, thanks to Toshiba. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

ShinyBaldy
08-24-2005, 02:04 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Hawkmoon230:
Hmm.........supercavitating.....

Rumour has it that the Russians were testing torps using this idea in the mid ninties, the main draw back for a sub is noise the proposion has to be some type of rocket motor which combined with the cavitation (a subs worst enemy even with screws) would give away the subs position. So a sub doing it well first off we can't biuld a usable rocket powered aircraft so imagine how much fuel a sub would need and don't start talking about plasma becaues a trail of ionised water leading right up your stern is the last thing a bout commander would want.

The most likly next major advance in sub tech' will be some type of induction drive where water can be moved through 'tube' via a 'non-mechanical system' this would allow far higher speeds to be reached with out the limitations of screws, the biggest being cavitation.

Just my 2 cents </div></BLOCKQUOTE>

pulser jet propulsion has already sorta elminiated cavitation problems with the screws... speed isn't really that important in the western philosophy of design anyway... particularly with diesel subs that aren't expected to conduct fleet operations.

paulhager
08-26-2005, 07:57 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Hawkmoon230:
Hmm.........supercavitating.....

Rumour has it that the Russians were testing torps using this idea in the mid ninties, the main draw back for a sub is noise the proposion has to be some type of rocket motor which combined with the cavitation (a subs worst enemy even with screws) would give away the subs position. So a sub doing it well first off we can't biuld a usable rocket powered aircraft so imagine how much fuel a sub would need and don't start talking about plasma becaues a trail of ionised water leading right up your stern is the last thing a bout commander would want.

The most likly next major advance in sub tech' will be some type of induction drive where water can be moved through 'tube' via a 'non-mechanical system' this would allow far higher speeds to be reached with out the limitations of screws, the biggest being cavitation.

Just my 2 cents </div></BLOCKQUOTE>

Noise is a sub's enemy because hydrodynamics and screw propulsion decree that a sub - even a nuclear sub - probably can't go much faster than 40-50 kts or so. That's not fast enough to compensate for the noise that brings inquisitive helos over your position dropping homing torps all around you.

If, on the other hand, a sub could travel as fast underwater as a jet in the air, we'd be talking about a completely different situation. Speed would become a defense and lots of water all around would be a shield.

Supercavitating torps were developed by the Soviets back in the 70's. There were practical problems with unguided though superfast torps that led the U.S. to not pursue the technology. Recent advances by the Soviets/Russians and now the Germans indicate that homing supercavitors are now practical. That changes things dramatically.

With respect to rockets - rocket planes have been around a long time. The Nazis used them in WW II. The Shuttle is a rocket plane. A big limitation is fuel+oxidizer requirements. It is worth noting that there were two different programs in the U.S. during the 1950s to build nuclear powered aircraft. Both demonstrated that the idea was sound. One program - the nuclear powered strategic bomber (the aircraft nuclear program or ANP) used a molten salt reactor for the powerplant. It was intended to run turbojets. The reactor+engine was demonstrated but the project was abandoned. You can probably find info about it from the Oak Ridge site. The second project was a nuclear powered ramjet guided missile - essentially a cruise missile. It used highly enriched uranium fuel. The engine was successfully demoed.

In point of fact, a nuclear powered single stage to orbit (SSTO) system could probably be built today that would operate much more economically and safely than the shuttle. It would not be politically viable because of anti-nuke hysteria. A "safer" and much more efficient reactor like a plasma core might reduce the political problems but plasma core technology has a bunch of technical problems to solve. If the feds eliminated most of the absurd regs and turned the private sector loose we might have have plasma core technology in 20 years - maybe less. A stepping stone would be the easier gas core technology.

My only point was that if we had plasma core technology for a power reactor then it could be used for a sub, just as easily for a rocket.

Baldricks_Mate
09-06-2005, 05:30 AM
The COLLINS class diesels (Australia) are a heap of sh*t. A classic case of a good idea poorly executed. The "Otway" class that preceeded them was much quieter even with their much older technology, which by the way, is the measure by which subs are judged. Ask a few US carrier skippers who were presented with close range recordings of their ships post exercises, coutesy of the "Otway's". Most embarrasing. I imagine the ASW people were keel hauled after. A "Collins" can't do that. The long lead time between conception, design, sale, then production means that there are quantum leaps in other technological areas. Suffice to say that the computer systems in one current & prominent sub class today use 486 chips..the software is also similarly limited. God help us!

WilhelmSchulz.-
09-06-2005, 09:28 AM
The Soviet project 641b or tango class subs are extreamly quite. Just as quite as the Alied nuc boats at the time. And since we didnt have as good sonar as we have now they where hard to detecet. So a tango could get into a fireing postion on a 688I but the LA clas subs are just as quite ao there more likely to sail eachother by.

Anton_Reinhold
09-06-2005, 10:20 AM
OK, I have no idea or even a guess about which modern era SS is the best but I do know some pros and cons when comparing diesel electrics to nuclear boats. The diesel electrics are definitely stealthier when submerged AND running on battery power. If you happen upon one that is on silent running routine, they will almost certainly get the first shot off which coincidentally will be how you come to know that there is one around. Now when they are running their diesels to recharge, they are noisy as heck! Nuclear submarines are alot faster and have one option that is not available to diesel electric submarines; they can go to flank speed in some cases and actually out run a torpedo. I do not say that they can go faster than a torpedo, but that the torpedo will not have enough time to get close enough to detonate before it runs out of power. Speed is definitely on the side of the nuclear boat. Another thing is that due to the great amounts of electrical power required to run the really good active sonars of these days, most if not all diesel electrics are lacking in this area. If a nuclear boat thought there was a diesel electric within range, they could go active, find it, launch torpeoes at it, and then go to flank speed and get out of there where as the diesel electric boat would only be able to fire a counter-attack and hope that the torpedoes can catch the nuclear boat. They will not have the speed and endurance needed to evade the incoming fish. Basically the diesel electric is an ambush-only design. It has to try and sit still for as long as possible, conserving O2 and amps while waiting for a target to come along. If they move around alot, they increase the need to recharge which makes so much noise that they lose their stealth totally. They are a tactical vessel where as a nuclear boat is more strategic in that it can move around alot more.
I do know that Russian and maybe even Chinese-made Kilos are selling like hot cakes to navies all over the world...

By the way, can we get a spell checker for this thing? http://forums.ubi.com/images/smilies/blink.gif

W.Irving
09-06-2005, 10:26 AM
The US Navy has borrowed a Swedish Gotland class submarine (the HMS Gotland) to practise detection with for a year (ending next summer).

http://www.1ubflj.mil.se/index.php?lang=S&c=news&id=29299 (http://www.1ubflj.mil.se/index.php?lang=S&amp;c=news&amp;id=29299)
Helen, a sonar operator, reports they're in San Diego, feasting on crayfish, at the moment.

We'll see in a year who has the quietest submerisble of them all! http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

kptltU-1312
11-27-2005, 07:39 AM
Some comments re Aussie Collins class subs.

it was the first ever attempt to build a submarine locally, if you can appreciate the complexity of that, prob 2nd to a spaceship?

true, there were teething probs, acustics and mission computer mostly i think. they copped a bucketing from the press, and thats all people think of. mainstream journos make terrible defence commentators & should stick to reporting cats in trees.

since then (years ago), some hull sculpting and new computers they are different boats. i believe they regularly 'defeat' SSNs, and ive seen what i believe are periscope photos of at least one US carrier. i also believe the USN now rates them as "formidable".

just had to set the record straight.
U-1312, out.

Celeon999
11-27-2005, 08:31 AM
Now that this old thread has popped up again i take the chance of posting an small update on the barracuda torpedo.


The Deutsche Marine still keeps the infos small.

Only news are that another prototype has been tested succesfully and reached 802 kilometers per hour and the last problems with holding the super cavitation bubble stable have been solved.

(How much m/ph and knots is this ? )


But ive found an small article that focuses on how the guidance system of the barracuda works.

It has a swingable nose. The torpedo takes the direction its nose pointes to.

http://img365.imageshack.us/img365/3379/superkavbgt3xa.jpg

http://img365.imageshack.us/img365/778/supkav28kq.jpg

How much renown for this thing ? http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

WilhelmSchulz
11-27-2005, 09:39 AM
1 trilion. http://forums.ubi.com/groupee_common/emoticons/icon_eek.gif

Baldricks_Mate
11-27-2005, 09:52 AM
If those things get loose, its time to get outa the sub business and find a very deep hole to hide in...it works for Bin Laden!

Schiffmorder
11-27-2005, 03:20 PM
Hands down winner: Norwegian Ula class, which is a derivative of the German 210. In 2004 winter nato excercises one Ula playing opfor successfully opposed the entire landing force, in order to get the landing done, the Ula was disqualified from participation.
There is a very good article here (http://www.nationaldefensemagazine.org/issues/2004/Aug/Diesel_Submarines.htm) on growing concerns over these types, and it actually mentions our favorite movie!!
The Russians.... nyet. No money, they invent nothing, steal **** near everything.
The Chinese on the other hand... their balance of trade is giving them cash out the ears, and they are using it to upgrade, and while not averse to stealing technology, they are also creators. Far more of a threat than Russians.

BONFLECK
11-28-2005, 12:45 AM
This is interesting................

http://www.subsim.com/ssr/page34.html

Celeon999
11-28-2005, 07:03 AM
Sometimes i think the russian navy is the uncrowned sad world champion in "self-sinking".

At least their u-boat force needs no enemys. http://forums.ubi.com/images/smilies/blink.gif

Schiffmorder
11-28-2005, 12:21 PM
This is a horrible article and subsim should yank it.
Exhibit A: <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Kursk's periscope was extended, indicating that it was at periscope depth
when the accident happened - the correct depth for launching a torpedo. </div></BLOCKQUOTE>
40 years ago this was true. Now? Once a solution if found the only limitation is having enough psi to blow the fish out the tube at whatever depth its at afaik.

Exhibit B:<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> It now also seems certain that nobody on the submarine survived longer than
60 hours, because no watertight compartments remained </div></BLOCKQUOTE>
Really? This sentence is self defeating, if no water tight compartments remained they didnt survive 60 seconds, much less hours. The truth is that there WERE water tight compartments, because some crew in back kept a log of their situation, and wrote final notes to loved ones.

Exhibit C: <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> Any members of the crew who may have survived had no time to close watertight
doors, or to send distress signals. Self-sealing emergency hatches failed
because the submarine's control systems were knocked out. </div></BLOCKQUOTE>

Oh please, this boat was participating in war games!! Simulated Combat! These two dunderhead authors suppose that while the forward half was targeting ships and shooting off torps that it was happy hour in the back?? Ivan is crazy, but he is not stupid! These people were at battlestations when this happened, you can bet the farm on it. That sub was battened down tight as a newborns ********, and that is the reason there were survivors in the rear for a while.

Celeon999
11-28-2005, 02:10 PM
I dont believe this Kursk sunk itself with a "new weapon" or Kursk was sunk by an collision with an american sub stories.


It was revealed over a year ago that an accident happened during torpedo loading while the Kursk was in port.

An holding chain broke on an crane and an torpedo crashed with its nose on the beton during the loading procedure.

Nobody noticed what happened , the torpedo looked undamaged so the port crew together with some crew men of the Kursk decided not to tell anyone what happened because they feared that they would be called responsible for the accident and would get into a lot of trouble.


The torpedo was loaded with the others into the Kursk.


It is now assumed that the torpedo may looked ok from the outside but recieved internal damage at this crash.

Some sort of liquid spilled out throughout the rear part of the torpedo (They mentioned what it was but i dont remember)


As the crew prepared their weapons for test firings the torpedo crew activated the batteries in this torp also.

This propably ignited an small fire inside the torpedo that wasnt recognized by the crew.

After a few minutes of internal burning the torpedo exploded directly in the torpedo compartment.

This was the first explosion (not so loud) recognized by land based sonar stations.

This was not the explosion that sunk the Kursk.

Most likely the entire torpedo crew was killed in this explosion and the torpedo compartment was on fire but not flooded. The captain ordered emergency surface.

The crew in the next compartments surely tried to extinguish the fire or simply tried to seal the entire weapons compartment off.

The source of the much louder secondary explosions that were footaged were propably the torpedo magazines that blew up as the fire reached them and heated the torps up to several thousand degrees. These powerful explosions (propably the first big bang after the initial explosion) destroyed the outer hull in the complete bow part of the Kursk.


This is considered the most likely scenario by now.

Schiffmorder
11-29-2005, 12:15 PM
Yeah I can believe that... that second explosion was huge! But it was a huge boat. Ahh well. I feel sorry for those poor sailors. Russia/Soviets always treated thier submariners like dirt, expendable dirt at that. Then they wonder why in a crew of 110 they need 44 'officers'. Incredible.

FI-Aflak
11-29-2005, 12:46 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by paulhager:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ShinyBaldy:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WilhelmSchulz.-:
Most subs now are bult for underwater paformince, just because its slow on the surface dosint mean its slow underwater. Renember the speeds for the Type XXI U-Boat? </div></BLOCKQUOTE>

I think Celeon999 was wondering why 20 knots was the max speed for even submerged... since the Type 212 and pretty much all diesel subs since the 1940s were hitting 20knots max speed. </div></BLOCKQUOTE>

Obviously drag is an issue. The real limit is imposed by cavitation because it generates so much noise. The top "tactical speed" is around 25kts. The old Soviet Alfa class attack sub was probably the fastest sub ever built. Supposedly, when one of those babies was cranked up to full speed it could be heard from one side of the Atlantic to the other.

So, a submarine that operates at a max of 20kts submerged isn't really at a disadvantage. In fact, diesel-electrics, when not snorkeling are quieter than nukes. Nukes, you see, can't get around the necessity to cool the reactor core (so far as I know, passive cooling isn't feasible with current technology). Cooling the core means running the pumps and that generates noise. Quieting nukes is therefore a considerable challenge.

The future of non-nuclear submarines is
Air Independent Propulsion (http://www.chinfo.navy.mil/navpalib/cno/n87/usw/issue_13/propulsion.htm) (AIP). The Swedish Stirling-engine system was profiled on one of the Discovery Channels (The Military Channel?) in a program about the new Virginia Class attack subs. Of note was the fact that women serve on Swedish subs. A great moment in the show was when a female officer - an archetypal nordic blonde - was being interviewed (in the sub) and one of her male crewmates walked through a hatch wearing only a tee-shirt and thong underwear. The woman took absolutely no notice.

But, I digress...

The ultimate non-nuclear propulsion system would probably be fuel cells. As noted in the link, the biggest problem is hydrogen storage. Metal hydrides were proposed decades ago as the way to store hydrogen for use as a portable fuel. Aside from safety benefits, hydrides actually store more hydrogen by volume than can be stored by liquifying it. There is, however, a weight penalty -- metal hydrids are heavy. </div></BLOCKQUOTE>

Metal hydrides can store 1-2% of their own weight in hydrogen, and any impurities in the hydrogen are left behind, reducing capacity. Under heat, this can be brought as high as 5-7%.

Carbon nanotubes, however, are capable of storing up to 65% their own weight in hydrogen. That's a huge number, of all the hydrogen storage techniques, I would guess CNT tanks to be the most promising.

Even today, metal hydrides are not the prime choice. You can store slurried Lithium Hyrdide (LiH) that is nearly 25% hydrogen by weight dry, less in the slurry but still significantly more than can be stored in a metal hydride tank. The lithium slurry is reacted with water to give Lithium Hydroxide and Hydrogen. The Lithium Hydroxide can be stored and reprocessed into lithium hydride fairly easily. yay for fuel cells.

paulhager
11-29-2005, 01:35 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by FI-Aflak:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by paulhager:
...


The ultimate non-nuclear propulsion system would probably be fuel cells. As noted in the link, the biggest problem is hydrogen storage. Metal hydrides were proposed decades ago as the way to store hydrogen for use as a portable fuel. Aside from safety benefits, hydrides actually store more hydrogen by volume than can be stored by liquifying it. There is, however, a weight penalty -- metal hydrids are heavy. </div></BLOCKQUOTE>

Metal hydrides can store 1-2% of their own weight in hydrogen, and any impurities in the hydrogen are left behind, reducing capacity. Under heat, this can be brought as high as 5-7%.

Carbon nanotubes, however, are capable of storing up to 65% their own weight in hydrogen. That's a huge number, of all the hydrogen storage techniques, I would guess CNT tanks to be the most promising.

Even today, metal hydrides are not the prime choice. You can store slurried Lithium Hyrdide (LiH) that is nearly 25% hydrogen by weight dry, less in the slurry but still significantly more than can be stored in a metal hydride tank. The lithium slurry is reacted with water to give Lithium Hydroxide and Hydrogen. The Lithium Hydroxide can be stored and reprocessed into lithium hydride fairly easily. yay for fuel cells. </div></BLOCKQUOTE>

Thanks for the update. I pretty much quit following the technology 20-odd years ago.

Carbon nanotubes are good for all sorts of things - potentially. I'm waiting for the space elevator...

Celeon999
11-29-2005, 02:03 PM
Talking about High-Tech


Have you seen the newest german army invention for the 21 century ?


http://img381.imageshack.us/img381/4271/b104qo.jpg

http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

FI-Aflak
11-29-2005, 08:58 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Celeon999:
Talking about High-Tech


Have you seen the newest german army invention for the 21 century ?


http://img381.imageshack.us/img381/4271/b104qo.jpg

http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif </div></BLOCKQUOTE>

Hell, I'd take those guys with one arm tied behind my back and a blindfold on.

Celeon999
11-30-2005, 03:21 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Hell, I'd take those guys with one arm tied behind my back and a blindfold on. </div></BLOCKQUOTE>

Like Arnold heh ? http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

FI-Aflak
12-01-2005, 01:36 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Celeon999:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Hell, I'd take those guys with one arm tied behind my back and a blindfold on. </div></BLOCKQUOTE>

Like Arnold heh ? http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif </div></BLOCKQUOTE>

Not quite. Ahh-nold was one of those guys. I am a creature the like of which is not seen even in terminator movies.