Can you Please resolve these Sub arguments???

[motsivad]

Me and my friend who both have an interest in subs, but are far less knowledgeable than some of the guys on here. Can you clear up one or two disagreements we have.

1) What is faster Nuclear propulsion, or modern day Diesel-Electric?

I always thought it was nuclear but he is certain that D-E is comparable. From my Knowledge the nuclear propulsed Alfa class is the fastest sub in the world and can easily exceed 40 knots and the LA class can do about 35+. From my knowledge D-E's tend to average mid 20s.

2) When submerged is Nuclear quieter or Modern day Electric?

I say former, he says latter

3) When surfaced is nuclear or Diesel quieter

I think it's gotta be nuclear, but he insists Diesel

[Platapus]

1. I would recommend reading the "speed thrills" series of documents at http://www.navweaps.com/index_tech/index_tech.htm Even though they deal with surface ships they address the complications of answering the question "what is the fastest" when comparing conventional and nuclear powered craft.

2. When submerged DE's are still quieter. Nuclear submarines still need cooling pumps and even sealed condensers can be noisy when the power level changes. Although we have some very smart ladies and gentlemen constantly working to make the nukes more sneaker.

3. An interesting question as nuclear subs don't usually spend a lot of their time on the surface. I would imagine that a nuclear sub would be quieter but that is just a guess.

[Oberon]

3. When SSKs are on the surface they're usually running on Diesels so they'd be a lot noiser, but if they're on batteries, I'd say they were quieter.

[Kapitan]

As said

Nuclear boats can go faster and sustain high speed for however long they want they are noiseyer than diesel electrics and AIP's but the nuclear boats can normaly dive alot deeper than thier diesel counterparts and also stay down longer and carry more weapons as they tend to be alot larger.

Fastest boat know at the moment was the russian papa (project 661 anchar)class 44.7 knots only to be suceaded on a run by an alfa (project 705k lira) class at 45.2 knots there was roumers the mike class (project 685 plavnik) was to be able to reach 38 knots however it was a failed design and never reached its top speed but it would out dive every modern nuclear submarine at the time and even today it can still out dive subs like seawolf and virginia diving to a maximum safe operational depth of 1020 meters (well over 3000 feet this is maximum safe depth crush depth was estimated at 5,100 feet)(source global security.org).

Given that the nuclaer boats are noiseyer they dive deeper so they can dive below a layer (thermocline layer where hot and cold water meet making sonar detection harder) an alfa at 200 meters could be heard a thousand miles away (source blind mans bluff tv prog from ret USN sub captain) however when dived right down to 650meter it was very hard in mid ocean to hear.

Its very rare that a nuclear submarine surfaces mid ocean its only when theres been an accident problem or on an exercise (EVEN THEN YOU WOULD BE LUCKY TO SURFACE).

There are three types of nuclear boats (main fleet not including specialist boats)

SSN attack submarine designed primarily for ASW and ASuW and in some cases land attack (688i springs to mind akula for russia)

SSGN a cruise missile submarine normaly larger than its attack submarine counterpart it carrys cruise missiles like the converted ohios and the massive russian Oscar II mainly used in the ASuW role (oscar II is designed for carrier battle group destruction) the ohios carry land attack missiles.

SSBN the biggest boats in the fleets carrying nuclear missiles the largest is the typhoon class (project 641 akula) of russia 562 feet long 86.4 feet wide and a submerged displacement of 48,000 tonnes (same wieght as the titanic and more than twice the wieght of britains current HMS Ark royal aircraft carrier and aprox 4,000 tonnes havier than the current LPDs in the USN)

on the surface a diesel boat would make more noise simply because the engine output is well above 150db (most subs reactors are about 60db forgot where i red this) also the waves crashing over the hull makes noise the properllor makes more noise in the sea when surfaced.


most diesel submarines are used for medium range sea going patrols and littoral operation (coastal) they carry a small crew 58 to 70 they are alot smaller meaning they can dive in shallower waters than a nuke they carry fewer weapons than nuclear boats (and some boats dont carry as good sensors as a nuclear sub the kilo (project 636 and 877 improved) dont have a towed array) most nuclear subs have towed arrays very very few now dont even SSBNs have TA's

But which one is the better submarine ?

It depends on what its about to do where its going and the conditions types of submarine used so niether one excells in all areas they are just good all around.

[Platapus]

Originally Posted by Kapitan

an alfa at 200 meters could be heard a thousand miles away

Wow!

[Kapitan]

Not uncommond its known publicly that many sonar sensors can pick other ships up thousands of miles away the ohios can track a ship the opposite side of the atlantic to them.

Dont forget sound travels further and faster through a liquid or solid than it does in gas (air) also a worthy note SOSUS the nets pin pointed K129 when she exploded in unknown circumstancies the nets were a good thousand miles away same with K219 scorpion and many other subs and ships.

[Raptor1]

I heard sonar operators near North America could hear the Alfas making 40 knots all the way off Murmansk

But those things are a special case, They don't need to be silent as they can actually outrun most of your torpedoes...

[Jimbuna]

Originally Posted by Kapitan

Not uncommond its known publicly that many sonar sensors can pick other ships up thousands of miles away the ohios can track a ship the opposite side of the atlantic to them.

Dont forget sound travels further and faster through a liquid or solid than it does in gas (air) also a worthy note SOSUS the nets pin pointed K129 when she exploded in unknown circumstancies the nets were a good thousand miles away same with K219 scorpion and many other subs and ships.

Very true....a friend of mine (sadly departed last month) was a PO Sonar on British subs and he told me they could pick up and identify from their individual sound signatures what liners were leaving the US Eastern coastal ports such as New York whilst lurking off the western coast of the UK.

[PeriscopeDepth]

Originally Posted by jimbuna

Very true....a friend of mine (sadly departed last month) was a PO Sonar on British subs and he told me they could pick up and identify from their individual sound signatures what liners were leaving the US Eastern coastal ports such as New York whilst lurking off the western coast of the UK.

Don't take this as an absolute though, it completely depends on acoustic conditions which change frequently. In absolutely perfect conditions is where this kind of stuff is possible. In absolutely terrible conditions a submarine with a decent sonar could still end up colliding with something that is loud. The way sound works in water is weird.

PD

[Kapitan]

very true this is most likely why we have so many problems finding the deisel boats in littoral waters due to the currents temprature and stuff.

[Kapitan_Phillips]

1) What is faster Nuclear propulsion, or modern day Diesel-Electric?

Nuclear, definately. All that I've read about have been able to outrun Diesel-Electrics

2) When submerged is Nuclear quieter or Modern day Electric?

Electric. Nuclear boats need essential systems to run the reactor to run at all times, silent running or not. With electrics, you can turn off all the systems without really risking the ship.

3) When surfaced is nuclear or Diesel quieter

This is a tough one. Nuclears bob and thrash alot on the surface, as they are designed to spend the majority of their patrol underwater. However, as is common knowledge, diesel engines, essential for recharging batteries, are very loud on the surface. On top of that, a D-E boat would spend more time ontop than a nuclear, so I'd give the nod to the Nukes.

Hope that helped

[PeriscopeDepth]

Originally Posted by Kapitan

very true this is most likely why we have so many problems finding the deisel boats in littoral waters due to the currents temprature and stuff.

Definitely! I am no expert; but what I understand is that acoustic conditions in the Persian Gulf, for example, generally suck more than in the Atlantic because:

- Water depth. Sound travels better in deeper water.
- Bottom type. No hard rock bottom to bounce sound around.
- Salinity, the amount of salt in the walter. This varies greatly in the littoral because salt water meets fresh water at rivers. It can play havoc with sonar conditions.
- Background noise. Tends to be greater near coastal shipping.
- Temperature. Sound travels better in colder water.

Weather also plays a part, but the weather in the Gulf tends to be pretty good and doesn't apply to my example.

You can see this for yourself in DW which models a lot of this stuff (maybe even all of it?). Set up two test missions, one in the North Atlantic with: good weather, in winter, convergence zone SVP, set bottom type to rock. Set up another one in the Persian Gulf in summer with: bad weather (rain, 20 knots of wind on surface, sea state of 3. we'll pretend it's a bad day in the Gulf to illustrate this), bottom limited SVP, set bottom type to sand. You should see drastic differences in tracking ranges.

PD

[TLAM Strike]

Originally Posted by Kapitan

Nuclear boats can go faster ... than diesel electrics and AIP's...

OBJECTION!!

The diesel sub USS Albacore AGSS 596 did 27.4 knots in 1953 the speed record for any sub at that time (the prevous was the German Type XXVIW at 24 knots using a walther turbine). Thats 5.1 knots higher than the Nautlus SSN 571 did two years later. In 1973 she reached 37 knots using contra-rotating props and poylamer ejection (again THE record sub speed record for that time, and the US Speed Record not broken until the Seawolf SSN 21 class of the 1990s).

[Kapitan]

Albacore was a research submarine though, but objection stands on the grounds its a submarine none the less, and was powerd by diesel electric.

BTW im not up on american boats and thier history

[FIREWALL]

Kapitan & TLAM Strike, I know who to ask when I have questions or probs when I play my 688i H\K ,SC or DW.

Thats for sure.