Project 885: Yasen class

Isos wrote:I wonder why they don't put some torpedo tubes to launch from behind against someone that follows the sub. They have some nice small torpedos that could take little space fir that task. Paket NK would be the best as it could target torpedos too.

I don't think I've seen many aft torpedo tubes on post-WW2 boats. The reason is that with modern guidance systems torpedo can turn around itself.

verkhoturye51 wrote:

Isos wrote:I wonder why they don't put some torpedo tubes to launch from behind against someone that follows the sub. They have some nice small torpedos that could take little space fir that task. Paket NK would be the best as it could target torpedos too.

I don't think I've seen many aft torpedo tubes on post-WW2 boats. The reason is that with modern guidance systems torpedo can turn around itself.

@Verkhoturye, @ Isos, obviously your knowledge doesn`t go further childish interest! None of submarines built after WWII, if they have one shaft, have stern launching TTs, because it substantially affects  hull form, increases noise and drag. making it practically impossible to mount stern tubes in modern one shaft design subs. Last western built SSK with stern tubes is french Daphne (two shaft) and soviet pr.641, NATO - Foxtrot (three shaft) submarine.

So, it has little to do with torpedo guidance, but it has a lot to do with principles of modern submarine engineering.

Except that western torpedo tubes are in the centre of the boat rather than extreme nose position, so why not have some facing forward and some facing back?

It would take up more room, but if firing backwards really was a valuable thing it should be doable.

Clearly they don't feel the need to have torpedoes facing backwards any more... and the real obvious question would be... why would you want that... you can't see very well through your propeller so it is a blind spot... why would you want to fire down the line of a blind spot?

Planes had rear gunners specifically because attacking fighters approached from behind because it was a blind spot and there fore a safer direction to attack from... until they put guns there of course.

GarryB wrote:Except that western torpedo tubes are in the centre of the boat rather than extreme nose position, so why not have some facing forward and some facing back?

It would take up more room, but if firing backwards really was a valuable thing it should be doable.

Clearly they don't feel the need to have torpedoes facing backwards any more... and the real obvious question would be... why would you want that... you can't see very well through your propeller so it is a blind spot... why would you want to fire down the line of a blind spot?

Planes had rear gunners specifically because attacking fighters approached from behind because it was a blind spot and there fore a safer direction to attack from... until they put guns there of course.

Some WWII German sub projects at closing stages of war had such arrangement - tubes fired from midships astern, but none of them were built, neither after the war there were such projects.

[quote="Labrador"]

GunshipDemocracy wrote:

Great graphic !

YW

BTW did anybody hear anything about Yassen/Kazan gym ?

They say Yasens have a gym and sauna, but we'll have to wait some time to find out more.

verkhoturye51 wrote:They say Yasens have a gym and sauna, but we'll have to wait some time to find out more.

All russian nuclear submarines starting from pr.971 Щука Б and pr.945 are as standard equipped with sauna, precisely "баня" which is a bit different from finnish sauna, and a small swimming pool. Akula, pr.941 - NATO Typhoon had swimming pool 7x3m, while in other subs it is smaller, say 5x2 or such. Gym is also standard equipment in newest subs, as is in american subs.

And maybe a smocking room also as in the Typhoon

kumbor wrote:

verkhoturye51 wrote:They say Yasens have a gym and sauna, but we'll have to wait some time to find out more.

All russian nuclear submarines starting from pr.971 Щука Б and pr.945 are as standard equipped with sauna, precisely "баня" which is a bit different from finnish sauna, and a  small swimming pool. Akula, pr.941 - NATO Typhoon had swimming pool 7x3m, while in other subs it is smaller, say 5x2 or such. Gym is also standard equipment in newest subs, as is in american subs.

There's no pool on Yasen class boats.

Waouw !
For to be difficult Kazan 885M don't have such 15/ Cooling water scoop Plavnik seems replaced by 2 grids more hydrodynamic
And VLS don't look as Mr GunshipDemocracy   have posted but i have see a pic with this design not square

http://www.hisutton.com/Pr885_Severodvinsk_Class.html
Large
http://www.hisutton.com/images/Ru_Pr885M_cutaway.jpg



885 Plavnik scoop



885M

kumbor wrote:

@Verkhoturye, @ Isos, obviously your knowledge doesn`t go further childish interest! None of submarines built after WWII, if they have one shaft, have stern launching TTs, because it substantially affects  hull form, increases noise and drag. making it practically impossible to mount stern tubes in modern one shaft design subs. Last western built SSK with stern tubes is french Daphne (two shaft) and soviet pr.641, NATO - Foxtrot (three shaft) submarine.

So, it has little to do with torpedo guidance, but it has a lot to do with principles of modern submarine engineering.

Two launchers 300mm torpedos won't change the external design, neither the noise. You say bullshit. Russian subs are huge there is plenty of room compare to western ones.

Clearly they don't feel the need to have torpedoes facing backwards any more... and the real obvious question would be... why would you want that... you can't see very well through your propeller so it is a blind spot... why would you want to fire down the line of a blind spot?

They have towed sonars which will be optimal to look behind the sub as the propeller will be in front of it. Paket against torpedo or ships following you while you escape would be a very good weapon against that sort of threats.

A sub isn't going to make a high turn at mach 1 taking 9g like a fighter jet. If it launched its torpedo against a close threat most likely it will be facing it and would need some minutes to complet a turn and get away. Modern torpedo are hard to jamm, I would prefer to have some paket that proved their efficiency.

Yasen got counter-measures launchers behind the turret. The old aft launching 533mm torpedos were huge, but the smaller 400mm torpedos of today would fit easily.

Hole wrote:Yasen got counter-measures launchers behind the turret. The old aft launching 533mm torpedos were huge, but the smaller 400mm torpedos of today would fit easily.

@Isos, if you have different opinion, would you please reveal the arguments. Name at least one submarine project in last 50 years, teardrop hulled - single shaft design, where stern launch weapons are used. Towed sonar arrays is a bit different thing. Only chaff launchers can be, sometimes, be mounted in the Sail (or turret, as somebody mistakenly says). With modern attack sub in silent mode, propeller/propulsor revving on minimum, when there is an enemy above you listening for every sound of yours - submarine complement is silent, speaking in whisper. Even if someone in submarine shouts by chance, or if a glass falls on the floor - it will make such noise that enemy will hear - and you`re dead, submarine lost with all hands! Every, even small protruding fin, winch or weapon tube at every speed above e.g. 4 knots, not to mention propeller/propulsor, makes such hydrodynamic noise that it can reveal position of the boat. I have noticed by myself, when diving with swimming fins, if I swim fast, say less than a meter a second. that my body produces clear hydrodynamic noise. I could hear it. Think about 60m, 1000 ton submarine, or something bigger! Every scratch is significant.

We are talking about a already detected sub. Two Subs close to each other, sort of a dogfight under water. A few small 400mm TR tubes (no reloads) behind the turret could help to fire a first shot even when the enemy is behind you.

For to be difficult Kazan 885M don't have such 15/ Cooling water scoop Plavnik seems replaced by 2 grids more hydrodynamic

That is pretty interesting actually
I was of the impression the scoops help the reactor cooling to work in no-pump mode so kinda surprising they'd be removed.
Must have altered the cooling loop so that it doesn't need the scoop?

hoom wrote:

For to be difficult Kazan 885M don't have such 15/ Cooling water scoop Plavnik seems replaced by 2 grids more hydrodynamic

That is pretty interesting actually  
I was of the impression the scoops help the reactor cooling to work in no-pump mode so kinda surprising they'd be removed.
Must have altered the cooling loop so that it doesn't need the scoop?

I think that Pr/885 has natural circulation type reactor! there are no pumps. One source of noise less.

Hole wrote:We are talking about a already detected sub. Two Subs close to each other, sort of a dogfight under water. A few small 400mm TR tubes (no reloads) behind the turret could help to fire a first shot even when the enemy is behind you.

Submarines have not "turrets". The construction housing enter hatches, periscopes, radar, aerials etc. in English is called FIN or SAIL, рус, РУБКА. In serbian/croatian it is "toranj", which can be translated as turret. I don`t know how it is in Polish (wieža?)

Concerning sail mounted TTs, it is problematical for reasons cited up. Long time ago I also tought it would be a good idea. Later I asked myself... I am not the only one so clever, OMG why nobody tried to make it in reality? Obviously there must be some problem if nobody projected and built such submarine. Some russian subs have decoy launchers in the sail. Russian decoys are roughly the size of a light torpedo, but these decoys are fired ahead or upwards! Nobody else had such an arrangement!

AFAIK decoys and the like are not fired through torpedo tubes... what happens in a fight when all tubes are loaded with torpedoes and you detect an incoming torpedo... unload the tube and load jamming decoys?

AFAIK jammers and decoys and defense aides have their own tubes...

Equally firing backwards is not really practical if you are towing a sonar array... it does not just drag straight and level... what happens if a rear fired torpedo hits it?

A submarine is not a fighter aircraft... torpedoes don't arm within 500m or more of the sub... otherwise a detonation could damage the launch sub as well as the target... so launching them forward and having them turn does make sense... especially if they are wire guided... you can launch them from the tube without their engine running and set them to turn and then start their motor so they would already have started turning before they accelerate to speed...

It is not just a torpedo tube facing backwards that takes up space, but you also need a loading area... plus of course torpedos are long... there wont be enough room to turn them around so you might have x number facing backwards and the rest facing forwards... but how do you know how many you will need to face forwards and how many face back because you can turn them around and you can't load them backwards... so odds are you will end up with torpedoes you don't use, or you will end up having to use the front tubes against targets behind and rear tubes for targets in front... so why just have all the tubes facing front and carry a lot more torpedoes...

kumbor wrote:

hoom wrote:

For to be difficult Kazan 885M don't have such 15/ Cooling water scoop Plavnik seems replaced by 2 grids more hydrodynamic

That is pretty interesting actually  
I was of the impression the scoops help the reactor cooling to work in no-pump mode so kinda surprising they'd be removed.
Must have altered the cooling loop so that it doesn't need the scoop?

I think that Pr/885 has natural circulation type reactor! there are no pumps. One source of noise less.

Exist since long time by ex Rubis class have but allow only a limited speed

Labrador wrote:

kumbor wrote:

hoom wrote:

For to be difficult Kazan 885M don't have such 15/ Cooling water scoop Plavnik seems replaced by 2 grids more hydrodynamic

That is pretty interesting actually  
I was of the impression the scoops help the reactor cooling to work in no-pump mode so kinda surprising they'd be removed.
Must have altered the cooling loop so that it doesn't need the scoop?

I think that Pr/885 has natural circulation type reactor! there are no pumps. One source of noise less.

Exist since long time by ex Rubis class have but allow only a limited speed

Pr.885 boats proved capable of 30 knots, if not a bit more. Natural circulation reactor is my guess, I am not sure of it.

@Isos, if you have different opinion, would you please reveal the arguments. Name at least one submarine project in last 50 years, teardrop hulled - single shaft design, where stern launch weapons are used. Towed sonar arrays is a bit different thing. Only chaff launchers can be, sometimes, be mounted in the Sail (or turret, as somebody mistakenly says). With modern attack sub in silent mode, propeller/propulsor revving on minimum, when there is an enemy above you listening for every sound of yours - submarine complement is silent, speaking in whisper. Even if someone in submarine shouts by chance, or if a glass falls on the floor - it will make such noise that enemy will hear - and you`re dead, submarine lost with all hands! Every, even small protruding fin, winch or weapon tube at every speed above e.g. 4 knots, not to mention propeller/propulsor, makes such hydrodynamic noise that it can reveal position of the boat. I have noticed by myself, when diving with swimming fins, if I swim fast, say less than a meter a second. that my body produces clear hydrodynamic noise. I could hear it. Think about 60m, 1000 ton submarine, or something bigger! Every scratch is significant

http://www.industrialnoisecontrol.com/comparative-noise-examples.htm

Boeing 737 or DC-9 aircraft at one nautical mile (6080 ft) before landing (97 dB); power mower (96 dB); motorcycle at 25 ft (90 dB).

Most of numbers I've seen for modern subs put their noise at 90-105 dB. You can compare with this link.

Those "not speaking into a sub because it can be heard" looks more to come from your experience with hollywood movies rather than submariners experience.

To track a sub you need constant noise to triangulate signal, a glass that falls on the ground isn't enough.

AFAIK jammers and decoys and defense aides have their own tubes...

Yes they have. They are much smaller than 533mm torpedo so no need to use a torpedo tube for them.

Equally firing backwards is not really practical if you are towing a sonar array... it does not just drag straight and level... what happens if a rear fired torpedo hits it?

A submarine is not a fighter aircraft... torpedoes don't arm within 500m or more of the sub... otherwise a detonation could damage the launch sub as well as the target... so launching them forward and having them turn does make sense...

You have your answer. If you can make it able to not touch the sub you can program them to not touch the sonar. Even if it touch it nothing will happen, the torpedo won't be fuzed and won't broke as the sonar is made of plastic.

A wire guided torpedo from the front to the back is dangerous because it can cut the wire. A torpedo launch will be heard by any modern sub. So when you launch it it gives away your position. So you need to be ready to get away and counter yourself enemy torpedos. With Paket-NK in you ass its easier ...

It is not just a torpedo tube facing backwards that takes up space, but you also need a loading area

Just for self defence. No need for reloads. You reload them at port with a automatic reloader that take the torpedos outside and bring them directly into the tubes.

Just for self defence. No need for reloads. You reload them at port with a automatic reloader that take the torpedos outside and bring them directly into the tubes.

So why not fit them between the inner hull and the outer hull like a vertical launch tube for a cruise missile... except have them facing backwards...

To track a sub you need constant noise to triangulate signal, a glass that falls on the ground isn't enough.

A human voice or breaking glass is not a natural sound in the sea and draws the enemies attention to your presence... in the Hollywood movies where they are ordered to stop talking or making noise is usually when there are ships above them looking for them, so presumably it would be easier to detect quieter noises...

Of course releasing a noise making device that moves like a torpedo but is more like a UUV that can generate various sound signatures and mimic events like a launch of a torpedo or its own decoys can make the game of cat and mouse all the more difficult...

Isos wrote:

@Isos, if you have different opinion, would you please reveal the arguments. Name at least one submarine project in last 50 years, teardrop hulled - single shaft design, where stern launch weapons are used. Towed sonar arrays is a bit different thing. Only chaff launchers can be, sometimes, be mounted in the Sail (or turret, as somebody mistakenly says). With modern attack sub in silent mode, propeller/propulsor revving on minimum, when there is an enemy above you listening for every sound of yours - submarine complement is silent, speaking in whisper. Even if someone in submarine shouts by chance, or if a glass falls on the floor - it will make such noise that enemy will hear - and you`re dead, submarine lost with all hands! Every, even small protruding fin, winch or weapon tube at every speed above e.g. 4 knots, not to mention propeller/propulsor, makes such hydrodynamic noise that it can reveal position of the boat. I have noticed by myself, when diving with swimming fins, if I swim fast, say less than a meter a second. that my body produces clear hydrodynamic noise. I could hear it. Think about 60m, 1000 ton submarine, or something bigger! Every scratch is significant

http://www.industrialnoisecontrol.com/comparative-noise-examples.htm

Boeing 737 or DC-9 aircraft at one nautical mile (6080 ft) before landing (97 dB); power mower (96 dB); motorcycle at 25 ft (90 dB).

Most of numbers I've seen for modern subs put their noise at 90-105 dB. You can compare with this link.

Those "not speaking into a sub because it can be heard" looks more to come from your experience with hollywood movies rather than submariners experience.

To track a sub you need constant noise to triangulate signal, a glass that falls on the ground isn't enough.

AFAIK jammers and decoys and defense aides have their own tubes...

Yes they have. They are much smaller than 533mm torpedo so no need to use a torpedo tube for them.

Equally firing backwards is not really practical if you are towing a sonar array... it does not just drag straight and level... what happens if a rear fired torpedo hits it?

A submarine is not a fighter aircraft... torpedoes don't arm within 500m or more of the sub... otherwise a detonation could damage the launch sub as well as the target... so launching them forward and having them turn does make sense...

You have your answer. If you can make it able to not touch the sub you can program them to not touch the sonar. Even if it touch it nothing will happen, the torpedo won't be fuzed and won't broke as the sonar is made of plastic.

A wire guided torpedo from the front to the back is dangerous because it can cut the wire. A torpedo launch will be heard by any modern sub. So when you launch it it gives away your position. So you need to be ready to get away and counter yourself enemy torpedos. With Paket-NK in you ass its easier ...

It is not just a torpedo tube facing backwards that takes up space, but you also need a loading area

Just for self defence. No need for reloads. You reload them at port with a automatic reloader that take the torpedos outside and bring them directly into the tubes.

@Isos, only film I can refer to is Das Boot, which is highly serious and real. I am not a submariner, but the main informations I`haven`t got from Hollywood films, but reading famous and professional books on submarine technology and history by Richard Compton-Hall, Richard Sharpe and yugoslav submariners - as Yugoslavia from 60s until 1991 has indigeniously projected and built seven fleet and six small submarines, with tradition of submarines dating from Austro-Hungary before 1918 and RYN between wars,

Kazan returned from its first outing

hoom wrote:Kazan returned from its first outing

Outing... what does it mean outing... you mean returned from first sea trials, or what?