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82 posters
Project 877/636: Kilo class SSK
Mike E- Posts : 2619
Points : 2651
Join date : 2014-06-19
Location : Bay Area, CA
- Post n°26
Re: Project 877/636: Kilo class SSK
Wow! They really are pumping these things out!
Viktor- Posts : 5796
Points : 6429
Join date : 2009-08-25
Age : 44
Location : Croatia
- Post n°27
Re: Project 877/636: Kilo class SSK
Another day and another Russian sub hits the water
Third diesel submarines for the Black Sea Fleet was launched in St. Petersburg
Third diesel submarines for the Black Sea Fleet was launched in St. Petersburg
Mike E- Posts : 2619
Points : 2651
Join date : 2014-06-19
Location : Bay Area, CA
- Post n°28
Re: Project 877/636: Kilo class SSK
Viktor wrote:Another day and another Russian sub hits the water
Third diesel submarines for the Black Sea Fleet was launched in St. Petersburg
Gotta love those Kilos!
Viktor- Posts : 5796
Points : 6429
Join date : 2009-08-25
Age : 44
Location : Croatia
- Post n°29
Kilo class submarines
5th and 6th Kilo class for BSF will be layed down by the end of 2014 on the same day
The last two "Varshavyanka" for the Black Sea Fleet will lay in one day
The last two "Varshavyanka" for the Black Sea Fleet will lay in one day
George1- Posts : 18510
Points : 19013
Join date : 2011-12-22
Location : Greece
- Post n°30
Imp Kilo/Kilo class submarine:
Third Varshavyanka class submarine for Russia’s Black Sea Fleet to be launched soon
ST. PETERSBURG, August 28./ITAR-TASS/. The third Varshavyanka class submarine - Stary Oskol of Project 636.3, built for Russia’s Black Sea Fleet, will be launched at the Admiralty Wharves Shipyard in St. Petersburg on Thursday.
Commander-in-Chief of the Russian Navy, Admiral Viktor Chirkov is expected to attend the ceremony.
A total of six Varshavyanka class submarines will be built for the Black Sea Fleet. According to the Navy commander, the submarines “will fulfil jointly with the naval surface forces and antisubmarine aircraft complex tasks in their responsibility zone.” They will also strengthen the combat capability of Russia’s naval task force in the Mediterranean.
The head submarine of the series - Novorossiysk, was laid down in August 2010 and delivered to the fleet in the presence of Russian Defense Minister Sergei Shoigu on August 22, 2014. After a voyage to the North it will pass two-week deepwater sea trials at the Northern Fleet ranges. Rostov-on-Don - the second submarine of the project and simultaneously the first series Varshavyanka for the Black Sea Fleet, was laid down in November 2011 and launched on June 26, 2014.
The Stary Oskol submarine was laid down in August 2012, and the fourth submarine of the project - Krasnodar - in February 2014.
The laying down of the fifth and sixth submarines of the class is planned in late October this year, for the 310th anniversary of Admiralty Wharves. The submarines will be named Veliky Novgorod and Kolpino.
The Varshavyanka-class third-generation diesel-electric subs were designed by the Rubin Central Design Bureau for Marine Engineering (St. Petersburg). Dubbed by the US Navy as “black holes in the ocean,” they are almost undetectable when submerged, designed for anti-shipping and anti-submarine missions in relatively shallow waters.
The submarines, armed with torpedoes, mines and cruise missiles, displace 3,100 tonnes, reach speeds of 20 knots, can dive to 300 metres and carry crews of 52 people.
ST. PETERSBURG, August 28./ITAR-TASS/. The third Varshavyanka class submarine - Stary Oskol of Project 636.3, built for Russia’s Black Sea Fleet, will be launched at the Admiralty Wharves Shipyard in St. Petersburg on Thursday.
Commander-in-Chief of the Russian Navy, Admiral Viktor Chirkov is expected to attend the ceremony.
A total of six Varshavyanka class submarines will be built for the Black Sea Fleet. According to the Navy commander, the submarines “will fulfil jointly with the naval surface forces and antisubmarine aircraft complex tasks in their responsibility zone.” They will also strengthen the combat capability of Russia’s naval task force in the Mediterranean.
The head submarine of the series - Novorossiysk, was laid down in August 2010 and delivered to the fleet in the presence of Russian Defense Minister Sergei Shoigu on August 22, 2014. After a voyage to the North it will pass two-week deepwater sea trials at the Northern Fleet ranges. Rostov-on-Don - the second submarine of the project and simultaneously the first series Varshavyanka for the Black Sea Fleet, was laid down in November 2011 and launched on June 26, 2014.
The Stary Oskol submarine was laid down in August 2012, and the fourth submarine of the project - Krasnodar - in February 2014.
The laying down of the fifth and sixth submarines of the class is planned in late October this year, for the 310th anniversary of Admiralty Wharves. The submarines will be named Veliky Novgorod and Kolpino.
The Varshavyanka-class third-generation diesel-electric subs were designed by the Rubin Central Design Bureau for Marine Engineering (St. Petersburg). Dubbed by the US Navy as “black holes in the ocean,” they are almost undetectable when submerged, designed for anti-shipping and anti-submarine missions in relatively shallow waters.
The submarines, armed with torpedoes, mines and cruise missiles, displace 3,100 tonnes, reach speeds of 20 knots, can dive to 300 metres and carry crews of 52 people.
George1- Posts : 18510
Points : 19013
Join date : 2011-12-22
Location : Greece
- Post n°31
Re: Project 877/636: Kilo class SSK
Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet
Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet
MOSCOW, September 17 (RIA Novosti) – Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet, the Southern Military District's press service said Wednesday.
The submarine currently remains at the Admiralty shipyard in St. Petersburg and will head to the Black Sea port of Novorossiisk after completing final trials with the Northern Fleet.
The Defense Ministry has ordered a total of six Varshavyanka-class subs, dubbed "black holes in the ocean" by the US Navy because they are nearly undetectable when submerged.
The Novorossiisk was laid down in August 2010. Back in August 2014, Russian Navy Commander Admiral Viktor Chirkov confirmed that two Project 636.3 diesel-electric submarines, the Novorossiysk and the Rostov-on-Don, would join the Black Sea Fleet by the end of the year. The construction of all six subs is to be completed by 2016.
The submarines are primarily intended for anti-ship and anti-submarine missions in relatively shallow waters. They will be crewed by 52 submariners, have an underwater speed of 20 knots and a cruising range of 400 miles with the ability to patrol for 45 days.
Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet
MOSCOW, September 17 (RIA Novosti) – Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet, the Southern Military District's press service said Wednesday.
The submarine currently remains at the Admiralty shipyard in St. Petersburg and will head to the Black Sea port of Novorossiisk after completing final trials with the Northern Fleet.
The Defense Ministry has ordered a total of six Varshavyanka-class subs, dubbed "black holes in the ocean" by the US Navy because they are nearly undetectable when submerged.
The Novorossiisk was laid down in August 2010. Back in August 2014, Russian Navy Commander Admiral Viktor Chirkov confirmed that two Project 636.3 diesel-electric submarines, the Novorossiysk and the Rostov-on-Don, would join the Black Sea Fleet by the end of the year. The construction of all six subs is to be completed by 2016.
The submarines are primarily intended for anti-ship and anti-submarine missions in relatively shallow waters. They will be crewed by 52 submariners, have an underwater speed of 20 knots and a cruising range of 400 miles with the ability to patrol for 45 days.
Mike E- Posts : 2619
Points : 2651
Join date : 2014-06-19
Location : Bay Area, CA
- Post n°32
Re: Project 877/636: Kilo class SSK
That is what I like to hear!
Viktor- Posts : 5796
Points : 6429
Join date : 2009-08-25
Age : 44
Location : Croatia
- Post n°33
Re: Project 877/636: Kilo class SSK
Excellent
Vladikavkaz modernized.
COMPLETED stacker stage of repair of submarines "VLADIKAVKAZ
Vladikavkaz modernized.
COMPLETED stacker stage of repair of submarines "VLADIKAVKAZ
TR1- Posts : 5435
Points : 5433
Join date : 2011-12-06
- Post n°34
Re: Project 877/636: Kilo class SSK
George1 wrote:Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet
Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet
MOSCOW, September 17 (RIA Novosti) – Russia's first Varshavyanka-class submarine, the Novorossiisk, has entered service with the Black Sea fleet, the Southern Military District's press service said Wednesday.
The submarine currently remains at the Admiralty shipyard in St. Petersburg and will head to the Black Sea port of Novorossiisk after completing final trials with the Northern Fleet.
The Defense Ministry has ordered a total of six Varshavyanka-class subs, dubbed "black holes in the ocean" by the US Navy because they are nearly undetectable when submerged.
The Novorossiisk was laid down in August 2010. Back in August 2014, Russian Navy Commander Admiral Viktor Chirkov confirmed that two Project 636.3 diesel-electric submarines, the Novorossiysk and the Rostov-on-Don, would join the Black Sea Fleet by the end of the year. The construction of all six subs is to be completed by 2016.
The submarines are primarily intended for anti-ship and anti-submarine missions in relatively shallow waters. They will be crewed by 52 submariners, have an underwater speed of 20 knots and a cruising range of 400 miles with the ability to patrol for 45 days.
Entered service into the BSF without being anywhere near the BSF.
Hmmm.
Stealthflanker- Posts : 1459
Points : 1535
Join date : 2009-08-04
Age : 36
Location : Indonesia
- Post n°35
Re: Project 877/636: Kilo class SSK
TR1 wrote:
Entered service into the BSF without being anywhere near the BSF.
Hmmm.
Guess it's pretty long way to get to the BSF base.
Other than that, would love to see better 636 with AIP in the future.
navyfield- Posts : 118
Points : 69
Join date : 2013-05-27
- Post n°36
Re: Project 877/636: Kilo class SSK
wasnt there a kilo with a pumpjet ,and in bsf, why new kilos dont have a pumpjet, its lack is a major drawback..!
Werewolf- Posts : 5927
Points : 6116
Join date : 2012-10-24
- Post n°37
Re: Project 877/636: Kilo class SSK
navyfield wrote:wasnt there a kilo with a pumpjet ,and in bsf, why new kilos dont have a pumpjet, its lack is a major drawback..!
Why you have nothing else but crying and bitching to contribute, lacking constructive post is a major drawback........::::!!!!!!
It wouldn't be painful to read all your comments if they were at least writen in an english accent. Now i have to read your comments in some funny accent just to overlook the dim content of your comments.
magnumcromagnon- Posts : 8138
Points : 8273
Join date : 2013-12-05
Location : Pindos ave., Pindosville, Pindosylvania, Pindostan
- Post n°38
Re: Project 877/636: Kilo class SSK
navyfield wrote:wasnt there a kilo with a pumpjet ,and in bsf, why new kilos dont have a pumpjet, its lack is a major drawback..!
According to the U.S. Navy the Improved Kilo's are considered "black holes" of the oceans, and like blackholes their both invisible and very dangerous.
Stealthflanker- Posts : 1459
Points : 1535
Join date : 2009-08-04
Age : 36
Location : Indonesia
- Post n°39
Re: Project 877/636: Kilo class SSK
navyfield wrote:wasnt there a kilo with a pumpjet ,and in bsf, why new kilos dont have a pumpjet, its lack is a major drawback..!
and why the F every diesel-electric sub out there still use conventional propeller ?
Being silent is sure nice BUT don't you ever think of clogging whenever the sub operate in coastal area ? Where the sea bed might be shallow.
Or perhaps loss of propulsive efficiency ?
Mike E- Posts : 2619
Points : 2651
Join date : 2014-06-19
Location : Bay Area, CA
- Post n°40
Re: Project 877/636: Kilo class SSK
Yeah, pump jets aren't without problems.... They are less efficient at lower speeds, which is a problem as diesels aren't known to be very fast... As Stealth said, they can be clogged with just about anything, and that problem gets much worse at the shallow depths the Kilos will operate... - Aka, they aren't any good for diesel powered subs! Most importantly, and this make you a hypocrite Navy, is that pump jets are much more complex and expensive. Which just happens to be your main argument *against AIP*!Stealthflanker wrote:navyfield wrote:wasnt there a kilo with a pumpjet ,and in bsf, why new kilos dont have a pumpjet, its lack is a major drawback..!
and why the F every diesel-electric sub out there still use conventional propeller ?
Being silent is sure nice BUT don't you ever think of clogging whenever the sub operate in coastal area ? Where the sea bed might be shallow.
Or perhaps loss of propulsive efficiency ?
That being said, pump jets can be worth while on larger subs and ships.
navyfield- Posts : 118
Points : 69
Join date : 2013-05-27
- Post n°41
Re: Project 877/636: Kilo class SSK
paltus submarine kilo class with a pumpjet is repaired and still serving in bsf.
navyfield- Posts : 118
Points : 69
Join date : 2013-05-27
- Post n°42
Re: Project 877/636: Kilo class SSK
oh please its just a simple shroud ,its nothing super mechanicaly complex ,however 2 propellers are used.Mike E wrote:Yeah, pump jets aren't without problems.... They are less efficient at lower speeds, which is a problem as diesels aren't known to be very fast... As Stealth said, they can be clogged with just about anything, and that problem gets much worse at the shallow depths the Kilos will operate... - Aka, they aren't any good for diesel powered subs! Most importantly, and this make you a hypocrite Navy, is that pump jets are much more complex and expensive. Which just happens to be your main argument *against AIP*!Stealthflanker wrote:navyfield wrote:wasnt there a kilo with a pumpjet ,and in bsf, why new kilos dont have a pumpjet, its lack is a major drawback..!
and why the F every diesel-electric sub out there still use conventional propeller ?
Being silent is sure nice BUT don't you ever think of clogging whenever the sub operate in coastal area ? Where the sea bed might be shallow.
Or perhaps loss of propulsive efficiency ?
That being said, pump jets can be worth while on larger subs and ships.
Stealthflanker- Posts : 1459
Points : 1535
Join date : 2009-08-04
Age : 36
Location : Indonesia
- Post n°43
Re: Project 877/636: Kilo class SSK
navyfield wrote:
oh please its just a simple shroud ,its nothing super mechanicaly complex ,however 2 propellers are used.
What the fuck you are talking about ? Pumpjet design have a book on its own, separated from propellers.
Seriously. You seem don't bother to use your brain eh ? What a waste.
Mike E- Posts : 2619
Points : 2651
Join date : 2014-06-19
Location : Bay Area, CA
- Post n°44
Re: Project 877/636: Kilo class SSK
Oh, you think I don't know that? I *clearly* pointed out to you that they have their own problems, and that they are more complex (the steering mechanism) yet here you are contradicting yourself! They are only worth while on a few types of vessels, and the fact that their is only *one* Kilo with a pump-jets should tell you that they don't want em'. The Borei will have them, but the Yasen won't.... - This admittedly confuses me as the Yasen should be the quieter of the two, correct? (Not to you Navy)navyfield wrote:oh please its just a simple shroud ,its nothing super mechanicaly complex ,however 2 propellers are used.Mike E wrote:Yeah, pump jets aren't without problems.... They are less efficient at lower speeds, which is a problem as diesels aren't known to be very fast... As Stealth said, they can be clogged with just about anything, and that problem gets much worse at the shallow depths the Kilos will operate... - Aka, they aren't any good for diesel powered subs! Most importantly, and this make you a hypocrite Navy, is that pump jets are much more complex and expensive. Which just happens to be your main argument *against AIP*!Stealthflanker wrote:navyfield wrote:wasnt there a kilo with a pumpjet ,and in bsf, why new kilos dont have a pumpjet, its lack is a major drawback..!
and why the F every diesel-electric sub out there still use conventional propeller ?
Being silent is sure nice BUT don't you ever think of clogging whenever the sub operate in coastal area ? Where the sea bed might be shallow.
Or perhaps loss of propulsive efficiency ?
That being said, pump jets can be worth while on larger subs and ships.
GarryB- Posts : 40489
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Join date : 2010-03-30
Location : New Zealand
- Post n°45
Re: Project 877/636: Kilo class SSK
Any specific technology will have advantages and disadvantages.
For instance a turbofan engine offers high thrust with fuel economy, while a turboprop engine offers fuel economy at subsonic speeds.
If the plane needs to be supersonic for part of its mission then you wont fit turboprop engines... that is just obvious.
Pumpjets will clearly be best at specific speeds... look at the propellers on the Akula class, they have ring shrouds to reduce blade tip cavitation...
For instance a turbofan engine offers high thrust with fuel economy, while a turboprop engine offers fuel economy at subsonic speeds.
If the plane needs to be supersonic for part of its mission then you wont fit turboprop engines... that is just obvious.
Pumpjets will clearly be best at specific speeds... look at the propellers on the Akula class, they have ring shrouds to reduce blade tip cavitation...
Mike E- Posts : 2619
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Join date : 2014-06-19
Location : Bay Area, CA
- Post n°46
Re: Project 877/636: Kilo class SSK
Those those ring shrouds make me think.... Aren't propellers very similar to fans (obviously in terms of propulsion) when it comes to aerospace/marine engineering? - As in, new technology is fans could have a similar advantage if used in propellers...
If so, than there are a bunch of ideas that should be implemented...
Blades that can flex (which reduce noise in fans) could (?) be used to improve the flow of water and pressure around the blades, possibly reducing cavitation and increasing efficiency... (They don't flex a lot, just to the right extent, but I doubt it would help.)
Having "shark skin" textures implemented on the blades, as they are already used on hulls should also increase efficiency.
Or connected blades could help as well (NB-eloop).
- Pump-jets are great, but they don't belong on diesel subs.
If so, than there are a bunch of ideas that should be implemented...
Blades that can flex (which reduce noise in fans) could (?) be used to improve the flow of water and pressure around the blades, possibly reducing cavitation and increasing efficiency... (They don't flex a lot, just to the right extent, but I doubt it would help.)
Having "shark skin" textures implemented on the blades, as they are already used on hulls should also increase efficiency.
Or connected blades could help as well (NB-eloop).
- Pump-jets are great, but they don't belong on diesel subs.
Mike E- Posts : 2619
Points : 2651
Join date : 2014-06-19
Location : Bay Area, CA
- Post n°47
Re: Project 877/636: Kilo class SSK
Here is a good file on detecting the Kilo via a SSN; http://www.dtic.mil/get-tr-doc/pdf?AD=ADA479975
Crazy to think that subs could be a couple miles away from each other, and have no clue that they are there!
Crazy to think that subs could be a couple miles away from each other, and have no clue that they are there!
magnumcromagnon- Posts : 8138
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- Post n°48
Re: Project 877/636: Kilo class SSK
Mike E wrote:Here is a good file on detecting the Kilo via a SSN; http://www.dtic.mil/get-tr-doc/pdf?AD=ADA479975
Crazy to think that subs could be a couple miles away from each other, and have no clue that they are there!
British and French nuclear submarine collision 'as serious as sinking of Kursk'
Mike E- Posts : 2619
Points : 2651
Join date : 2014-06-19
Location : Bay Area, CA
- Post n°49
Re: Project 877/636: Kilo class SSK
Pretty crazy! Makes me wonder why countries don't put more attention on submarines, rather than something like a useless Zumwalt.... To think that a single nuclear sub could sink an entire carrier convoy...magnumcromagnon wrote:Mike E wrote:Here is a good file on detecting the Kilo via a SSN; http://www.dtic.mil/get-tr-doc/pdf?AD=ADA479975
Crazy to think that subs could be a couple miles away from each other, and have no clue that they are there!
British and French nuclear submarine collision 'as serious as sinking of Kursk'
GarryB- Posts : 40489
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Join date : 2010-03-30
Location : New Zealand
- Post n°50
Re: Project 877/636: Kilo class SSK
Those those ring shrouds make me think.... Aren't propellers very similar to fans (obviously in terms of propulsion) when it comes to aerospace/marine engineering? - As in, new technology is fans could have a similar advantage if used in propellers...
While there are similarities there are a lot of differences too.
First of all the obvious is that blades in water need to be very strong because water does not compress and to move it takes a lot of energy... though when you get it moving it generates a powerful thrust.
In air the air is much thinner and lighter, be to fly you need reduced weight because weight on an aircraft is bad. On a ship or sub is its totally unimportant.
On an aircraft an array of fans all in front of each other is more efficient as the front fans accelerate the air back into a tube, the next fan blades can assume the air is already travelling fast and in a fairly uniform flow so they can be angled to accelerate the air even faster etc etc... after 4-5 sets of fan blades you can bend the tube so it gets narrow, which will compress the air dramatically, which will heat it... fuel can be added to heat it further and it can then expand the tube and blow the air out the back... moving fast and hot.
That is a basic description of a turbojet engine.
With a shaft down the centre you can attach the blades just after the fuel is added in the hot section to the front blades so as you add fuel and the blades in the hot section move faster the front blades move faster too sucking in more air and increasing the thrust of the engine as you throttle up.
After burner injects fuel into the exhaust further adding heat and thrust.
A turbo fan basically has a turbo jet at its core, but if you greatly increase the width of the tube at the front along with the fans and design it so that where the tube narrows for the hot section where the fuel is added there is an outer tube that bypasses the hot section, so cold air sucked in by the front fans is split... a small amount going through the narrow hot section and the rest going around the outside of the hot section. the difference is that you are moving a much larger mass of air. The extra air is colder to which can reduce the IR signature of the exhaust gas in normal cruise mode.
the most important thing however is that at the exhaust there is hot turbo jet air moving fast with lots of energy and there is also a much larger mass of slower moving bypass air which hasn't had fuel burnt in it so it is much more oxygen rich, so when you put on the afterburner the fuel burns much more efficiently and you can add more fuel and generate more thrust with a turbo fan engine.
On a boeing however the bypass air is enormous and the small turbojet is just there to drive the big fans at the front so most of the thrust is from the big fans.
I should note that when I call bypass air cold, I mean in the sense that it is no where near as hot as the air going through the turbo jet... it would still burn you as it is highly compressed in the process of going through the engine...
On submarines... particularly on SSBNs the main focus is in dealing with blade tip cavitation and blocking any noise it might create.
Blades that can flex (which reduce noise in fans) could (?) be used to improve the flow of water and pressure around the blades, possibly reducing cavitation and increasing efficiency... (They don't flex a lot, just to the right extent, but I doubt it would help.)
Movable blades... whether they flex or are variable pitch seem to be very rare in submarine design... the strength needed along with very specific speed regimes... plus the need to reverse as well as go forward seem to dictate very very precisely designed and cut big heavy metal propellers.
I am no expert in sub prop design.
Having "shark skin" textures implemented on the blades, as they are already used on hulls should also increase efficiency.
The speeds that propellers move while the vessel is moving suggests rough skins might increase cavitation rather than decrease it... remember cavitation not only generates underwater noise, it also leads to physical damage to the blades.
Crazy to think that subs could be a couple miles away from each other, and have no clue that they are there!
So basically this is the US Navy admitting that it can't effectively detect the current SSKs that Russia builds for export with passive means and it has to use active sonar for effective detection.
Active sonar would be fine against one Kilo trying to penetrate US waters, but in the middle of the ocean or near Russia where there might be hundreds of ears listening out for subs just how well will active sonar work in spotting SSKs?
The obvious answer is that they would have to operate assuming SSKs are around and undetected and get on with their mission because if they actively ping to look they are dead.