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Thread: Russian Navy : News & Discussion

  1. #31
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    This is great news , I think it would require 3 more launches to get Initial Operational Clearence , So Late 2006 seems to be achievable , I think the only hinderance for it was the Bulava.

    Since Bulava is based on Topol-M , Much of the missiles System and Subsystem has been throughly tested and Operational. The Russians claims that Borei would be the most silent SSBN when launched compared to any other operational SSBN or any thing there on drawing board .

    Its heartening to know that Russia's N-Submarine fleet reamins Top Of The Line inspite of difficulties faced through out the past decades.

    So does Bulava carries a single warhead with lots of decoys like Topol-M or is it a MIRV'ed missile, Any news on its range ???.

    RSM55 thanks for the info you have provided , After reading the information on Severodvinsk that you have provided , It seems like very little is know about it , It should have neen operational by now , It would be very interesting to know if Sev or for that matter even Borei would have a convetional 7 Blade Skewed Prop or Pump Jet Propulsion.

    Also it would be interesting to see if Severodvinsk has been designed for Litorral warfare and Special Force Ops like the US Virginia SSN or for Blue Water Operation like the Sea Wolf class.

    Any information on that would be interesting
    "A map does you no good if you don't know where you are"

  2. #32
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    A pump-jet would make a lot of sense for Borey atleast. I also hope that they manage to make the launch tube fairings somewhat more hydrodynamical than some of those (speculative?) models show. Would be cool if Bulava carried the hypersonic glide vehicle that has reportedly been tested in recent years.

    My guess is that Severodvinsk will be a blue water sub along the lines of the Seawolf, unlike the US Russia still has excellent (and compact) SSKs to fill the litoral requirement.

  3. #33
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    I doubt the Seawolf can really best the upgraded Akulas...

  4. #34
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    Hello Guys!

    RSM55 I have some questions regarding your always intersted comments:

    Quote Originally Posted by RSM55
    2) the sudden and tremendous improvement in noise level reduction was not at all sudden and not tremendous and is the MMM is therefore not to be credited for all the apparent noise level reduction,
    A question regarding noise level reduction techniques in Soviet Submarines. Wich was the first submarine that used the active noise cancellation technique?. I have reports that both, 971 "Schuka-B" since first series and 667BRDM introduced it. No idea if 945/945A used it. Now, accord to an article writed by a 1st Rank Captain some time ago at "Red Star" Jurnal, talking about "Sankt Petesburg" 677 Lada SSK, this technique "only now" could be used due to extenous needs in computer processing that were not in service then...What's the true regarding ANC?...it was improved since them?.

    Which advances do you think were the main bosters to noise level reductions in Soviet subs since 671RT?... I know 671RT (Victor-II) introduced rafting techniques for noise reduction of the main machenry systems. You mentioned 671RTM used 2 tandem 4-blade screws (but I have what seems a pic of a 671RTM with a typical 8-blade screw, in fact the Victor-III that participated in the "TASS" actions out of American Coasts in 1984 (the affaire in wich a Victor-III get caught in a Towed Array Sensor of an american Frigate under tests). I'm pretty sure the pic I saw was an 8-blade screw and not a tandem one...If I pass you the picture could you help me?.

    Anechoic tiles (wich Soviet submarine did introduced it?) was a main factor regarding active-sonar reduction levels, but noise-level reductions?. I know because Soviet Nuke Boats like 671RTM uses two-hull arrangements, they used to use anechoic tiles in the outer hull (against active sonar) and in the inner hull (against sound from the submarine's machinery). Was this arrangement efective?. Did 671RTM introduced it?. I have some information (pretty basic one) regarding new generation anechoic tiles used in 971 "Schuka-B", in that they were 2 and half inches of thickness...anything similar for 671RTM? (as you could see I'm very intersted in this sub family (671xx) I'm doing an essay about them.

    Accord to a non-secret chart of the US Navy late-80s-early 90s about broad-band noise levels of both american and soviet/russian sub (you could find it at FAS.org per example) they comment on TWO Victor-III clasess. One Victor-III and "an Improved Victor-III". Improved Victor-III is clasiffied as having lower noise-levels that "Akula" (basic one)...

    Now I would guess this was "guess-stimation", but an Improved Victor-III should be 671RTMK from Leningrad Yards, that benefited from Toshiba MMM for improved screws. Were 671RTMK better in noise-levels than basic 671RTM?. I think I could infere something like that from your message, thanks to improved screws. Curious that 945/945A/971 used (still?) soviet designed MMM for milling screws and were far better than 671RTMK in this field!...anything that you could add to this?...

    About Nuclear Reactors, Norman Polmar's book "Cold War Submarines Design", said that Nuclear reactor for 945 used "natural circulation" while at low speeds (5-to-6 knots) making no use of pumps. Now, did 971 used also this technique?...was natural circulation reactores further pursued by Soviet Designers or introduced in any other Soviet/Russina Nuke boat?...

    And now (IMHO my most important question to you), is...WHAT impulsed the soviet Navy and designers to pursue such ambitious noise-reduction-levels programs since 1975(or so) when 945 and 971 plus 671RTM were developed?....what was the "detonant" that made the Soviets to consider so-seriously the noise levels of their subs, and what allowed them to improve so much in so much little time?...people talk about John Walker espionage ring (this was trully fatal to the US Navy without any doubt), other people talks (wrongly as you named) about Toshiba 9-axis MMM...I have some "information" that Soviet Navy Glakvom was not that intersted in knowing how bad were the sound-levels of their boats and how good were those of the americans in the late-60s-early-70s (have you readen Rising Tide?, its mentioned there with some Intell-gathering activities examples...). While I could see (and we have proves of this) that quality controls improved a lot (vastly a lot) since the second generation Soviet nuke boats (Victor, Delta, etc) over the very problematic first generation boats (HEN family accord western nomenclature), was this process as far-reaching to allow the extraordinary improvements of the 945/971 combo in noise-reduction levels?

    Hope you can help me on this, if you need quotes to the Rising Tide book, told me out.

    What's definitely true is that older Soviet milling machines were certainly not as good as Western ones, and the Leningrad yards were glad to get something better than their usual Almaz milling machines with Bulgarian electronics. It's one of the strangest discrepancies of the Soviet legacy: while retaining state-of-the-art material science on the R&D level (from metallic alloys to nanotechnologies), Russian heavy machinery construction is still in its infancy viewn from a technological level (which is quite amazing if one considers the huge number of soviet/russian enterprises that feature a "-mash-" morpheme in their name).
    Yes. Polmar mentioned in the above-volume a conclusion assesment that was pursued when Nikita Khruschev asked "why could we not develop a faulty-free industrial basis to copy such a hardware as Sidewinder missile but the americans could do it" (not exact phrase thorugh), mentioning that main problem of Soviet Industry was the second-rate Industrial basis that result of the surviving german's invation to the Soviet Union. This could never fully develop in the comunist system due to lack of consumers and cross-R&D of consumer goods and military goods...

    How this improved or not in the submarine-field I don't know...what's your opinion?

    1) No, actually the new (tandem-screw, 2x4 blades) propellers were already chosen as the main system during the construction of the first RTM batch. And the first sub to use the noise-reducing experimental tandem scheme was actually the first 671RT (K-387 built in Gorki at the Krasnoe Sormovo yard and modified in Leningrad Admiralterskyie yards)!
    RSM55 maybe I'm asking the same thing two times, and I ask you an apology if I'm doing so (my english is not so good), but while 671RTM introduced tandem screw 2x4 blades, did the ones of the 671RTMK that benefited from Toshiba MMM machines were better?. Did K-387 received tandem screws as a part of an overhaul/upgrade or from yard?...

    2) It is sometimes said that the "K" in RTMK was added to the subs that received SOKS (not Kolos). That's only partly true: some "clean" 671 became 617K after being fitted with SOKS while some 617RT modified along the same line didn't receive any appendix at all. On top of that, K-502 (Commander: Cpt1r Smetanin) was a RTMK without SOKS but with a very characteristic bulbous appendix on the foredeck right after the fairing (6m long, 1,5m wide/high) hiding an experimental "Granat" launch pad and the experimental "Akatsia" targeting C3 system (using the same hardware as the "Omnibus" overall C3 suite but having a "battle post" of its own, namely BTch-2 while OMNIBUS was located in BTch-7).So much for consistency!
    Thanks!...let me try to understand all of this:

    *671RTMK were the only Victor-III subs that could use "Granat" SLCM isn't?
    *No other 671 family ship could use "Granat" (if so, wich ones?, and when were they allowed to do it?) Is there any pic of K-502?, didn't found anything at deepstorm.ru.
    * SOKS was installed mainly in the 671RTMK but also in some other boats of the 671 class (as you mentioned one 671 "vanilla" used it to track a Lafayette SSBN during Aport Operation). Was the same SOKS system used in 945 and 971?. I have a pic of the sail of the 971 that shows what I'm fully sure of be "SOKS" system. It was in Polmar Cold War Submarines designs and he mentioned it was used to measure "radioactivity, turbulence, temperature and other phenomenas"...photo could be showed if you want. Would be a SOKS derivative be installed in 955 and 855 proekts?
    * The thingie of the Command Posts. Polmar book talks about 971 using an integraded GKP or "main command point" like the one in the "Lira" class of Interceptor SSN. I'm a little bit confused with the platforms of the 671RTM/RTMK, so let me try to understand it:

    671RTM used first Viking and then Omnibus? or it was the inverse?, you talk about a BTch-7, what is exactly this?, is a part of Omnibus or is Omnibus a part of BTch-7?...what did BTCh means in russian BTW?

    K-502 uses "Akatsia" special targetting C3 system for use of the Granat system. Did K-502 also used basic "Omnibus" command post?. You mentioned having a "battle post" of its own, namely BTch-2, I don't understand this, could you explain it to me?...sorry, soviet submarines are trully difficult to understand some times ...have to research more...

    Did Viking system really derived from that used in the "Ula" class of Norwegian SSK as some western sources mentioned?...

    SOKS is a very sensitive (for its time) "keel-water wake detection system" (Sistema Obnarujenia Kilvaternovo Sleda) derived from the first Soviet torpedo-mounted systems. During Operation Aport the K-147 (a "clean" 671 fitted with the SOKS and the experimental MNK-100) managed to follow a Lafayette-class (probably Simon Bolivar) SSN for more than 6 days (other sources say it was a Los A. SSN, but it's hard to believe). The point is: you can't detect anything just with the SOKS, you need (passive) acoustics as well (because of basic physics) and the whole thing's name is MNK-100: the wake of a sub changes the density of the water, filling it with microscopic bubbles. This effect can last for hours and hours, so you need to go through a complex process of measuring these parameters when they're still detectable through acoustic (passive) and hydrooptical means (as it seems that trying to detect this effect by measuring the relative salinity values has not proved reliable).
    OK, clear enough. Now, what is the experimental MNK-100?, is a sensor that fuses the SOKS and Sonar (active/passive) information?, was this MNK-100 installed in the other SOKS-users of the 671RTMK/945/945A/971 proekts?. Is SOKS perturbable by what class of phenomena?, I guess it would not suffer of high self-contained noise levels in 671 class SSN. if you're intersted, in Morskoi Sbornik in 1/1994 edition it was mentioned that an 671RTMK sub (the ship under the command of Captain 2nd Rank R.A Stakheyev) mantained contact with a Los Angeles Class SSN during one-day-and a half using non-acoustic sensors. The captain mentioned that he lit on the active sonar at the end of the track...

    Yes and no. RTM(K) were the first subs in the Sov.Union to receive an integrated battle information system (BIUS), and the first was called "Viking". It was afterwards completely (and very painfully) replaced by the more advanced "Omnibus".
    Is (BIUS) the same thing as (GKP)?, I mean Integrated Battle Information System is the same as Main Command Post?. Why was the Viking system replaced from 671RTMK by Omnibus and why it was painfull?...

    4) Problems arose mainly from the difficulty of towing back the array in the bulbous canopy of the Ruza system. Skat (all systems) is said to have been highly reliable.
    Great. This info along the down you provided me is just awesome, many thanks!. So the Towed Array system is called "Ruza"?...I guessed it was called Piton...well who knows!...

    Let me try to understand Sonars used in Victor series:
    671 receieved "Rubin" series (let's forget the MGK number, unless you're intersted in provided it!)
    671RT received improved "Rubikon"
    671 while in overhaul received "Rubikon"
    671RTM/RTMK received "Skat-KS" same as 945. The version used in 671RTM/RTMK and 945 used analog processing of the signal.

    Now, did any Victor III receiev flannk arrays like those of the 688 class?. Did the 945/945/971 used too the same "Ruza" system as the 671RTM?...did those boats received flank arrays.

    In the west its mentioned that "Akula's sonar could only track 2 targets at the same time contrary to multiple ones of the 688 and the former being much less sensitive than AN/BQQ-5"...any opinion regarding this?

    Morphyspribor, the NII that developed these sonars said this:

    As for Morphyspribor’s primary profile, over the past two decades it has developed new-generation submarine sonar systems with digital data processing, such as MGK-500, MGK-520 and MGK-540 which are currently in service with all modern Russian submarines. These systems fully incorporated all the best features of the domestic sonar design. They also used the traditional approach to achieve «duel parity» with U.S. subs which had better acoustic characteristics until the mid-1980s (lower noise level, low manifestation of discrete elements in the noise radiation range, etc.). This approach required antennas of larger dimensions than those of the U.S. AN/BQQ-5,6 sonars. Larger antennas and, consequently, their multiple channel capability required additional costs for processing equipment. At the same time, the domestic electronic industry lagged behind the U.S. sonar industry in terms of equipment integration, capability and miniaturization. This factor caused a significant growth in the dimensions of domestically-made sonar hardware and its power consumption. To counterbalance these shortcomings, Morphyspribor researchers devised unconventional design and algorithmic solutions which were more efficient and economical than those used in the world practice. For example, target classification was resolved by Morphysbribor by using target «behavior» features which were even more stable in adverse signal propagation and jamming conditions.
    Any information regarding this "target behaviour" features introduced in the Skat series of DSP Sonars?

    5) Yep, both Akula and Sierra have non-acoustic sensors. Strangely enough, the acoustic suite of the Sierra is less efficient than the Akula's (Skat-KS with analogue processing) but this is probably compensated by greater operational depth. Countermeasures are still classified for all subs (they have been used during "Aport" and "Atrina" ops though), however, it is possible that the experimental, 300m/sec 2nd stage submarine rocket APR-3M can also be launched individually and not only with the first stage, as a "last chance to cut-the-wires" means.
    But from what I know, both 945 and 971 have the same "test depth" at 600m without regarding its different class of hulls...

    Have you heard of the "Impostor" decoy?...was this thingie used in Atrina/Aport?

    Thanks a lot for your help pal!

  5. #35
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    This is the article I wa taking about regarding active noise cancellation.

    Any comments?

    (c) Vladimir GUNDAROV, Captain 1st Rank

    [..]
    Project 677 Lada continues the line of 636s and 877s (Kilo, according to NATO classification), which for their low noise levels were dubbed in the West as the "Black Hole"). We can be proud of our new achievements, because basic performances of Sankt Peterburg are two to three times better than those of third-generation boats in combat efficiency.
    The new submarine belongs to the fourth generation and features a number of fundamental differences. Above all, it is the high degree of automation of centralized control of all shipboard systems and weapons from operator's consoles located in the main control room. The torpedo and missile system was made more powerful. Design offices, research and production associations and scientific research institutes have all contributed to that. Among them are CDB ME Rubin, NPO Avrora, FGUP TsNII Elektropribor, OKB Novator, and NPO Agat. A result of their joint efforts is the CLUB-S. It is an integrated missile system which represents a unique development that is in fact unmatched by anything else in the world.

    Russian scientists, designers and builders have in fact made a breakthrough in technical and economic characteristics and technology in the Lada class. Dozens of new solutions were proposed in the course of research and development. All armaments, boat systems and materials are the last word in science and technology. The sonar system, for example, is built around the latest microchips and with the latest software. Located in the forward end is a highly sensitive sonar array. A fundamentally new all-purpose multi-functional periscope is installed. The hoisting mast devices are telescopic. They do not enter the pressure hull, with the exception of the attack periscope. A new system for receiving radio information from the shore in the submerged position has been introduced.
    [..]

    The Achilles' heel of all our submarines, with the exception of the Kilo-class submarine and the Project 971 nuclear-powered submarine, has been their high underwater noise levels. Between 1968 and 1986, the CPSU Central Committee and the USSR Council of Ministers issued four (!) decisions on this problem. Every six years it was requested to reduce the noise level by 50 or 70 per cent. All of these instructions were fulfilled, except for the last one when work on this theme was halted because of lack of financing. Lastly, the nuclear-powered multi-purpose submarines of Project 971A managed to reduce the underwater noise level by 30 decibels, or in noise pressure terms by 96.7 per cent, and in irradiated sound power terms, by a thousand times!
    Last month, one of these submarines — K-157 Vepr — demonstrated its soft catlike movement during an official visit to the French port of Brest.
    But Sankt Peterburg is not for nothing described as the successor to the "Black Hole". Its noise level is approaching sea background values. And in concealment it will surpass all submarines built earlier not only in this country but also abroad.
    In Heaven's name 30dB noise reduction levels!!!, is this true?, what is a 971A class?, Gepard?, Vepr?.

    How could this be achieved? The answer was given at a state scientific centre called the Krylov Shipbuilding Research Institute (KSRI). Fourth-generation submarines are provided with specially developed noise-absorbing — down to low frequencies — rubber coatings only 40 mm thick. They are half as thick as those we used before. The new coating consists of 7 to 8 layers of rubber with different perforations and profiles. The idea is simple: the more air cavities there are, the more effectively they absorb noise of different frequencies and at different depths. This was said by Professor Ernst Myshinsky, Doctor of Engineering, head of the shipboard and industrial acoustics department.

    But hydro-acoustic coating is only a passive defense against noise. And the Institute is already working on new tools for active defense. According to the scientist, development of such means of noise suppression is a super new direction in world science. In Russia the active methods appeared a quarter of a century ago, but then they were considered to be a "medicine", like nitroglycerin.

    "Twenty-five years ago electronics was appalling. And we all feared that instead of creating an anti-sound — a sound in the anti-phase — we could knock out electronic controls. And the noise, on the contrary, would intensify," says Myshinsky. "But now electronics are normal, and so it is time to develop active comprehensive system of noise reduction."
    It is possible that they may appear on the next submarine, which will be built after Sankt Peterburg.


    [..]

    Better Than Energiser

    Stale TV advertising about batteries "that will work, work and work" would look deflated if developers of "hydrogen batteries" for the Sankt Peterburg boat dared to put their ware on the air waves.

    Thirty years ago TsKB Lazurit, NPO Kvant and Kriogenmash embarked on the development for submarines of propulsive systems with electro-chemical generators, ECGs. The S-273 submarine of Project 613, which was mentioned above, was converted under Project 613E Katran. While conventional submarines at two-knot speeds could not stay under water for longer than four days without battery recharging, the use of electro-chemical generators increased this period to a month.

    A second area in which Russian designers work is development of Diesels operating in a closed cycle. Project 615 with a single engine was put into metal in the middle of the last century and marked a unique event in the world.

    Since 1978, the Special Boiler-Building Design Office has been the leading developer of propulsive systems with ECGs It drew on the experience of the Urals electrochemical works and NPO Energia that developed ECGs for spacecraft. In that way, a Kristall-20 engine for submarines made its appearance, using oxygen and hydrogen. The latter is present in bound form — in an intermetallic compound. Second-generation Kristall-27 and Kristall-273 engines can now also be installed on new Diesel-electric submarines, increasing their endurance to 45 days. Without divulging all secrets of Russian shipbuilding, we may say that the endurance of Sankt Peterburg is exactly 45 days.

    Amur, Cousin of Lada
    Just like the German Howaldtswerke Deutsche Werft AG, Admiralteiskiye Verfi, in parallel with the Lada class sub for the Russian Navy, is also building for export a fourth-generation submarine of Amur-1650 class. They are almost look-alikes. Amur will be able to fire missile salvoes against surface single and group targets. Compared with submarines of the previous projects, its acoustic signature is several times lower. It also carries radioelectronic equipment of a new generation.

    Automatic ship control, and management of its combat and technical systems, will be effected from the main control room. An inertia navigation system will ensure safe navigation and determination of movement parameters while staying under water for a long time with an accuracy sufficient for missile weapons. Amur will have an all-mode propulsion electric motor of a new type, and also a storage battery with an extended service life.

    Like Lada, the export unit is equipped with a highly sensitive array of the Lira sonar system. The outer hull is covered in Molniya anti-sonar coating of a new generation.
    FGUP Admiralteiskiye Verfi is contributing financing to the development of an air-independent propulsion unit for use as an alternative source of electricity.

    Everything for Sale
    Admiralteiskiye Verfi has what financiers describe as a good credit history. By 2002, it had handed over to foreign clients thirteen submarines of Projects 877EKM and 636, i.e. more than half of boats of this class built in this country. At the same time, it repaired four vessels.
    New output of the enterprise will also find its consumers. The most promising market, according to specialists, is South East Asia. Among the probable buyers of Amur-class submarines are Vietnam, Thailand, and the Philippines. Last century Russia sold about 50 submarines. It is not ruled out that in the 21st century products of Russian shipwrights will still be in demand on the international arms market.

  6. #36
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    I can't claim to have the same level of knowledge on this topic as RSM55, but...

    Quote Originally Posted by Pit
    Which advances do you think were the main bosters to noise level reductions in Soviet subs since 671RT?... I know 671RT (Victor-II) introduced rafting techniques for noise reduction of the main machenry systems. You mentioned 671RTM used 2 tandem 4-blade screws (but I have what seems a pic of a 671RTM with a typical 8-blade screw, in fact the Victor-III that participated in the "TASS" actions out of American Coasts in 1984 (the affaire in wich a Victor-III get caught in a Towed Array Sensor of an american Frigate under tests). I'm pretty sure the pic I saw was an 8-blade screw and not a tandem one...If I pass you the picture could you help me?.
    I think I have a relatively clear version of the picture you're talking about in a book, it's usually a bit misleading because it was apparently taken into the sun. Perception of depth is very bad because basically every surface facing the camera is pitch-black. However if you look closely you can see spray behind one of the blades that seems to be covering part of the neighbouring blade. This would indicate tandem screws.

    Quote Originally Posted by Pit
    Anechoic tiles (wich Soviet submarine did introduced it?)
    VictorII according to another book I have.

    BTW, I found this image which claims to show the Lada's new anechotic coating on another forum:
    Attached Images Attached Images  

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    Russian Sierra-I nuclear submarine soon back in active service
    2005-09-29 19:22

    The repairs at the Russian multipurpose nuclear submarine K-276 ”Krab” (project 945, Barrakuda) have been completed recently.

    At the moment the submarine has finished sea trials and is moored at the shipyard for painting and correcting defects noted by the acceptance committee, Interfax reported. It is expected that the submarine will be back in active service in the end of 2005. At the same time the preparation works for repair works on another submarine of this class are carried out at the moment.

    Krab joined the Northern Fleet in 1987. It has been presumably in reserve since 1997. Four submarines in total of this class were built in Russia. The first submarine of this project (K-239, Karp) was taken out of service in 1997-98.

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    After reading briefly it seems that the Sierra-I/II hulls are made up of Titanium , which will allow greater Diving Depth( between 800 to crush depth of 1500+ meteres) and also has range of Non Acoustic sensors and Silencing capabilities.Besides carrries 40 weapons ranging from cruise missile to Torpedoes and an intergated countermeasure capability, It seems that she is the most *difficult* to detect submarine , Plus for the Sierra-2 has a spherical sonar besides improved quitening than Sier-1 ( but it remains debatable if ever the Sierra-2 was ever constructed ).

    This is the most interesting development as far as Russian N-Subs Development are concerned.

    So Why has there been a sudden need to resurrect these subs ( just because they are relatively new ) , Or its upgrade capability give her an edge over the Akula-2 , Or perhaps the capability of the Sierra was so vastly advanced that the RuN is compelled to bring her back to service.
    Last edited by Austin; 9th October 2005 at 05:42.
    "A map does you no good if you don't know where you are"

  9. #39
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    Or perhaps the capability of the Sierra was so vastly advanced that the RuN is compelled to bring her back to service.
    Or perhaps they are largely complete and the cost of making those already made operational is lower than building brand new Akulas from scratch even if they do work out cheaper over all?

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    Sierra II never had a sperical bow sonar, you're talking about Sierra III, the project Mars. They had five of them on the building stocks in 1992, all were abandoned and scrapped. Sierra II was constructed... Two of each. Kostroma is called Krab by most, but Kostroma by the Russians! Here is a picture of her refurbishment (in this case a new escape chamber). It's a Sierra I so why refurbish one of those? This one isn't that superior to Akula.

  11. #41
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    Akula class SSN was constructed because it was difficult to produce titanium sufficiently (in industrial quantity ) to keep pace with the Sierra requirements , Also from what I have read Titanium is not the easiest of metal to deal with and tends to be unpredictive at depths ( internal/miscroscopic cracks which cannot be detected easily ) .

    As far as superiority of Sierra is concerned , It has been quoted in Western Def Magazine that she can easily pass through the NATO/US SOSUS network without getting detected

    There must have been compelling good reasons ( Financially/Operationally ) to ressurrect her , Inspite of the fact that the Russian could have gone for more Akula-2/3 ( the 2 unfinished one ) or could have invested in the Severdovinisk SSN program .

    Did any one heard any thing new on the Severodivinsk SSN program ??

    Which is the second one of the Sierra class being repaired to make it operational ??
    "A map does you no good if you don't know where you are"

  12. #42
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    Tula collided and is laid up.
    Both Sierra IIs, Kondor and Nizhniy Novgorod are officially in service, but both of them are in a worsening state of readiness, not sure they can still sail.

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    K-336 Pskov, suffered a little fire while being in overhaul in 2003, read this:

    Nuclear submarine on fire

    A Sierra class nuclear-powered submarine caught on fire Wednesday while in dry dock.
    Dry dock of naval shipyard no. 82 in Roslyakovo.
    Nils Bøhmer/Bellona

    Igor Kudrik, 2003-03-06 15:25

    A Sierra I attack class submarine, K-336, or Pskov, suffered a fire on March 5th. The submarine was in the dry dock at Roslyakovo shipyard, situated between the city of Murmansk and Severomorsk, the home base of the Northern Fleet, on the Kola Peninsula.

    Fire crews called to the shipyard managed to put the fire out in one and half hours, Russian news agency ITAR-TASS reported.

    The cause of the fire is still unknown, but it may be possible that the welding works ignited the wood scaffolding surrounding the submarine.

    No causalities or radiation discharge are reported, although the rubber coating of the submarine is damaged.

    A similar incident took place in October last year when an Echo II submarine was undergoing decommissioning at Sevmorput shipyard, located in the north of Murmansk. The fire also started on the wood scaffolding in the dry dock surrounding the submarine, and then spread to the rubber coating of the submarine.

    The Soviet Union built four Sierra I class attack class submarines, or SSNs. The fifth submarine, which would be a Sierra II class, was decommissioned at the staples in 1993. The Pskov, which entered service in 1993, is the newest nuclear-powered Sierra I class submarine. The first Sierra class submarine, K-239, retired from service in 1998. The two remaining submarines allegedly remain in service. Sierra class submarines are equipped with one PWR reactor and titanium hull.

  14. #44
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    Neptune, you're correct, K-276's (since 1992 tactical code changed to B-276) name isn't Krab (no more), because since November 15, 1996 it received the name Kostroma. This ship while being called K-276 back in 1992 collided with SSN-689 "Baton Rouge" in the Kola Peninsula, it was laid up and repaired and it returned back to service months after. It was interned in SRZ Nerpa Shipyard in 2000 and its now ready to return to the fleet.

    First boat of the Pr 945, the B-239 "Karp" was retired back in 1998, and there are two other proekt 945A "Kondor" Sierra-II boats in service whose destiny right now is not known. Pskov suffered a fire in 2003 while on repairs/overhaul, and the other boat nobody knows...

    Regards

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    Hi guys, first of all my apologies for "disappearing" from your radar screens, have been away and far from any WWW plug...
    Will try to answer your questions as well as I can:

    Quote Originally Posted by Pit
    ...regarding noise level reduction techniques in Soviet Submarines. Wich was the first submarine that used the active noise cancellation technique?. I have reports that both, 971 "Schuka-B" since first series and 667BRDM introduced it. No idea if 945/945A used it. Now, accord to an article writed by a 1st Rank Captain some time ago at "Red Star" Jurnal, talking about "Sankt Petesburg" 677 Lada SSK, this technique "only now" could be used due to extenous needs in computer processing that were not in service then...What's the true regarding ANC?...it was improved since them?.
    When one tells something about noise reduction, better ask him what's his/her defininition is... Noise reduction techniques have been used since WWII at the latest, ANC is a matter of definition as well. I suspect that the Red star report is actually about an all-active NC technique, thanks to which it would be possible to cancel internal radiated noise (especially pump and reductors noises) by insulating them with active conduction apparatus that radiates at inversed acoustic wavelenghts and -pitch levels (similar approaches have been tried in 4/5th gen. fighter jets, e.g. Rafale - applied to radar detection of course). Now, this sounds well in theory, but in practice you need extremely accurate internal sensors and an enormous processing capacity, neither of which was available in the SU (and even in the US). You just reach a technical barrier at one stage. And you also need to model all your aggregates and apparatus exactly, having a database that can't include all the possible noises and noise levels... Plus, this kind of ANC is not a panacea, as it can properly operate only at low radiation levels (i.e. at low speeds for ex.). The best technique is yet to combine ANC and passive noise reduction tech such as anechoic, contact-free internal frames with active movement cancellation: this, however, supposes you have enough space (so big displacement), which is not appliable on the Lada, what should explain why the Russian navy was so eager to introduce this "new ANC" on that type of boat.
    BTW, I would be extremely critical of anything published in Red Star, not only because it's the official MoD paper, but especially for the reason that their redactional level is extremely poor and a lot printed there is pure PR.


    Quote Originally Posted by Pit
    Which advances do you think were the main bosters to noise level reductions in Soviet subs since 671RT?... I know 671RT (Victor-II) introduced rafting techniques for noise reduction of the main machenry systems. You mentioned 671RTM used 2 tandem 4-blade screws (but I have what seems a pic of a 671RTM with a typical 8-blade screw, in fact the Victor-III that participated in the "TASS" actions out of American Coasts
    You're absolutely right, that was the K-324. If I remember well, it was the 7th vessel of the Komsomolsk line and she was modified in 1985, so after the incindent you mentioned (dated 1983 AFAIK).

    Quote Originally Posted by Pit
    Anechoic tiles (wich Soviet submarine did introduced it?) was a main factor regarding active-sonar reduction levels, but noise-level reductions?. I know because Soviet Nuke Boats like 671RTM uses two-hull arrangements, they used to use anechoic tiles in the outer hull (against active sonar) and in the inner hull (against sound from the submarine's machinery). Was this arrangement efective?. Did 671RTM introduced it?. I have some information (pretty basic one) regarding new generation anechoic tiles used in 971 "Schuka-B", in that they were 2 and half inches of thickness...anything similar for 671RTM?
    The first anechoic tiles were used (experimentally) in the Lira project, both for active sonar effective range reduction and noise reduction (the latter were applied directly to the inside of the strong hull, which proved to be absolutely useless). In-between hulls arrangements proved to be highly efficient for some wavelengths, but led to an increase in acoustic radiation when the wavelength was consistent with the space between both hulls (classical raisonnance box effect). Thickness of the anechoic tiles is not consistent with their effectiveness, it only reflects advances in manufacturing (increase of inner "worm holes"). The Victor family had quite a basic coating that could not radiate the active pings away in the water in a very effective way. The other reason was that the Victor was hydrodynamically not as "perfect" as the Lira (the hull of the latter was in itself "anechoic" as its mere form acted as a diffusion factor for incoming pings).

    Quote Originally Posted by Pit
    Accord to a non-secret chart of the US Navy late-80s-early 90s about broad-band noise levels of both american and soviet/russian sub (you could find it at FAS.org per example) they comment on TWO Victor-III clasess. One Victor-III and "an Improved Victor-III". Improved Victor-III is clasiffied as having lower noise-levels that "Akula" (basic one)
    This report's aim is to prove that the Toshiba gimmick did its job. Its statements are not consistent with what my sources tell me, and if I believe them, RTMK doesn't come near Akula in terms of noise reduction. Akulas benefited from the Toshiba MMM as well anyway. And it's quite strange to mention broad-band radiation when the matter is about screws...So I'll consider this report with a lot of caveats.


    About Nuclear Reactors, Norman Polmar's book "Cold War Submarines Design", said that Nuclear reactor for 945 used "natural circulation" while at low speeds (5-to-6 knots) making no use of pumps. Now, did 971 used also this technique?...was natural circulation reactores further pursued by Soviet Designers or introduced in any other Soviet/Russina Nuke boat?..


    Yep, some say that 971 benefits from the same feature (also at low speed levels). Don't know about the Sierras, though. Quite sure that later 949As ,the 941 and later BDRMs have it as well (in spite of dissimilar reactors but for reasons obvious enough).

    Quote Originally Posted by Pit
    And now (IMHO my most important question to you), is...WHAT impulsed the soviet Navy and designers to pursue such ambitious noise-reduction-levels programs since 1975(or so) when 945 and 971 plus 671RTM were developed?....what was the "detonant" that made the Soviets to consider so-seriously the noise levels of their subs, and what allowed them to improve so much in so much little time?
    This is a very good question indeed, and I'm glad to be able to answer it. However, I have to warn you that you won't find any corroboration for my info anywhere, as this matter remains quite shrouded to this day due to reasons that have nothing to do with naval stuff. The "detonant", as you put it, was a man killed in a plane crash on Feb. the 7th, 1981, alongside with 50 top brass officers of the Soviet Pacific Fleet: Admiral Emil Nikolaevitch Spiridonov. He was an excellent specialist, the most highly skilled and the most able soviet naval commander of his day, and enjoyed enormous respect and authority within the Navy establishment. His was the impetus that shifted the focus from quantity to quality. As the Commander of the Pacific Fleet, he knew too well (contrary to the Northern Fleet officials) that he couldn't rely on on-shore support and closed seas in case of war, and his sub commanders were extremely honest in their reports to him. Gorshkov, on the other hand, was enamoured with speed , it was the only factor that seemed interesting for him for a sub to have. Spiridonov assembled an excellent group of top officers under his command who devised a long-term strategy for the whole Fleet, which still remains valid to the present day, and managed to force Gorshkov to implement it. Unfortunately, as said above, he died after attending a command exercise in Leningrad, after the Fleet's Tu-104 failed to take-off and crashed short after the runway. 50 of his best officers and friends (16 generals and admirals among them!) died instantly. The question about the need to pack the best brains of the Fleet in a single outdated plane that even Aeroflot didn't want to fly anymore remains unanswered. All the inquiry conclusions remain classified. I'll leave the rest to conspiracy theorists...



    Quote Originally Posted by Pit
    ...while 671RTM introduced tandem screw 2x4 blades, did the ones of the 671RTMK that benefited from Toshiba MMM machines were better?. Did K-387 received tandem screws as a part of an overhaul/upgrade or from yard?...
    No, the decision to replace them with tandem blades extended to ALL Victor III subs, the upgrade having been discontinued for costs reasons (and the venue of the Akula). K-387? If you mean K-388, yes.


    *671RTMK were the only Victor-III subs that could use "Granat" SLCM isn't?


    No. K is not consistent with Granat, regardless what open sources tell. Some RTMKs could use Granats, some RTM also. But only the Sierras and Akulas effectively got cleared for their use.

    * SOKS...?
    Yes, an improved version is installed on the 971s. Pretty sure that Yasen and Borei will have it as a part of their standard a-suite.

    *
    The thingie of the Command Posts. Polmar book talks about 971 using an integraded GKP or "main command point" like the one in the "Lira" class of Interceptor SSN. I'm a little bit confused with the platforms of the 671RTM/RTMK, so let me try to understand it:

    671RTM used first Viking and then Omnibus? or it was the inverse?, you talk about a BTch-7, what is exactly this?, is a part of Omnibus or is Omnibus a part of BTch-7?...what did BTCh means in russian BTW?
    K-502 uses "Akatsia" special targetting C3 system for use of the Granat system. Did K-502 also used basic "Omnibus" command post?.


    Understand your confusion. "Viking" was the first BIUS on the 671RTM, replaced by "Omnibus". "Omnibus" is a battle command system, not a battle post. BIUS means "Boevaya Informatsionno-Upravlayushaya Sistema": litteraly, "battle command and information system". The first viable BIUS was the "Accord" on the Lira. GKP simply means "main command post", so it denotes an actual location in the sub. "BTch-X" means "battle station-X", i.e. the actual battle station in the Xth watertight compartment (but the numbers are not always consistent with the compartments). A BIUS comprises many sub-systems, so "Akatsia" is a dedicated targeting system and is integrated in the Omnibus BIUS.
    Using metaphors:
    *any BIUS = LAN Network
    *GKP = main server room
    * "Akatsia" and the like = external drivers, printers, mouses etc.
    * "BTch-X = your working cubicle with family photos and bonzai.
    Omnibus was painstacking to integrate because of electronic incompatibility with some other components, vibration over-sensitivity, poor microchip reliability and tendency to over-heat (looks like Microsoft tried to do some hardware there...).

    Quote Originally Posted by Pit
    ...what is the experimental MNK-100?, is a sensor that fuses the SOKS and Sonar (active/passive) information?, was this MNK-100 installed in the other SOKS-users of the 671RTMK/945/945A/971 proekts?. Is SOKS perturbable by what class of phenomena?
    Yes and yes. SOKS is perturbable by transient and irregular water conformation: abnormal salinity, abnormal waterflow, wake and the usual bathycelemetric layer dead zones. And if something blows up somewhere near and disturbs the water patterns, you'll have to start from the beginning.

    AFAIK no flank arrays like the ones on the 688 were used in the Victor series. Flank arrays on the Akulas are probably a subsystem of the SOKS, but who knows...

    Skat sonars include parallax and dynamic analysis algorithms that enable them to scan a database of known SSN/SSBN acoustic and mouvement patterns and compare them automatically. Put in a dumb way: something that sounds like a shrimp but makes a V-turn every 14 seconds travelling at 7 knots due North is not shrimp. No one knows for sure how many targets a modern Russian SSN can track simultaneously.

    [QUOTE=Pit]
    From what I know, both 945 and 971 have the same "test depth" at 600m without regarding its different class of hulls...
    [QUOTE]

    Published "test depth" figures are the greatest hoax since the Philadelphia experiment. You know what is the "official" "test depth" of an Antey according to recent Russian publication? 300 m

    [QUOTE=Pit]
    Have you heard of the "Impostor" decoy?...was this thingie used in Atrina/Aport?
    [QUOTE]

    I pass here, pal. Never heard about anything called "Impostor". What is it?
    Last edited by RSM55; 11th October 2005 at 17:48.

  16. #46
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    Hello all,
    I have been researching Russian submarines for years. I friend gave me this link and I am amazed!!
    I just returned from the Ukraine for the second time this year after visiting an Alfa officer I have been writing for years. A few months back, I was in Balaclava walking around in the underground submarine pen there.
    I have some "pretty good" pictures and video of some Russian boats, including drydock photographs of the Alfa, Akula, and Typhoon.
    My research was origionally started because I am building radio controlled Russian submarines.
    I see a lot of talent and information here. I am really excited to talk to you guys.
    Let's go for a starter.
    There was a Kilo made and based in Severostopol a few years back with a pumpjet.
    I have always heard a distant rumor one of the Akulas has one. I have managed to obtain drydock photographs of all of the Akulas except one (an Akula II).
    Has anyone else heard this? It would seem natural for them to try one. It could even be justified as a testbed for the Borley. I have also heard this boat will have one.
    Anyone?

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    Gepard, the only actual Akula II around, has a normal propellor.

  18. #48
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    Impostor is a torpedo decoy something with a noisegenerator, maybe her other name, MG-74 Korund rinkles a bell with you? The Victors, Sierra's and others carry it. There's some arguing about it. It's said to be mounted in the Akula's external 533mm tubes, two in each tube. It would be logical to have some decoys in there as you can't reload these tubes anyway. On the other hand six extra weapons ready to fire is some advantage is some situations. The other SSNs only carry two of them, so it's quite doubtful the Akula's carry 12 of them.

    wouldn't indeed believe Krasnaya, the PR is the only reason for their existence. It saved them.
    Last edited by Neptune; 11th October 2005 at 21:39.

  19. #49
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    Pumpjets on Akulas

    This is the dockyard picture of the Gepard.
    Attached Images Attached Images  

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    RSM55, thanks A LOT for your answers! (Trident too pal !!) the part about Spiridinov was just awesome and trully revealling!, I would research more on this, did you recommend any literature about this intersting character?...

    The time you take to answer was WORTH the value of the answer really!, as Neptune said, Impostor, is what you call MG-74 "Korund", maybe that's the traduction, but who knows!?...

    Would return later with more comments , keep the god job pal

  21. #51
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    P.S: Gatorfrey, please fell free to add any picture, link, information or video you want to add about Soviet/Russian Nuclear Boats!

    If you can send any material (specially regarding those in-dock pictures of 971 Akula) to my e-mail address pit_m_viniegra@yahoo.com.ar, would be most grateful!...

    Regards

  22. #52
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    Pit,
    You should have a couple of teaser shots of my pictures in your email.
    Someone said the Gepard is the only actual Akula II. Why is the Vepr not considered an Akula II ? It is extended and has the extra hull sensors as the Gepard has.
    My photographs show quite a bit. Including closeups of the retractable creeper motors on the Akula II. As I said, I have drydock pictures of each of the Akulas of various configurations, except one. The Cougar.
    Let me try my question in a different fashion. What information is out there on Russian pumpjets? Other than the one drydock picture of the Kilo that is common on the net, I find almost nothing on it. I understand a few years ago, there was a second picture on the net of that Kilo that got pulled out of circulation.
    That is all I have been able to find out about the Russian pumpjet in general, other than the Borely will probably have one.
    I have written a few storys and published in a magazine on the Alfa, Akula, Typhoon, and Beluga. I am very interested in these classes, and all others as well.

  23. #53
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    Cool Oscar 2 Silencing?

    Likewise, Gatorfrey,

    any pictures of Akulas in dock would be warmly appreciated. My email is bars971@yahoo.co.nz

    By the way, what what does everyone think of the accuracy of these drawings and RSM55 in particular, how quiet are the Oscar IIs? We always hear about the Schulka B's but what of the Antey 949A's?
    Attached Files Attached Files

  24. #54
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    Gatorfrey thanks for anything you send!

    971:

    There are different "batches" (if you want to call them in that way) of pr 971 "Schuka-B" (Akula) made in the USSR/Russia. As we know, 971 were built in two yards, Komsomolsk-na-amur (Zavod Imeni Leninskogo Komsomola N199) and at Severodinsk (Severnoe Mashinostrel'noe Predpryatie N 402) from 1983 to 1993 (dates of first boat being lay down at Komsomolsk to date of last boat being lay down at the same place (Drakon/Samara), last at Severodinsk in 1991, ony counting finished vessels!)...

    The first boats built at Komsomolsk are "what we call" "Akula" in the west, and they're the basic vessels. Once the first project 971 vessel was being tested, a lot of potential was found for further noise-level reduction capabilities, those capabilities, were introduced "mainly" (I don't know if any Komsomolsk boat taked it) from the second boat being constructed at Severodinsk (Pantera) and introduced afterwards...those boats being built at Severodinsk after "Pantera" (not sure of those ones being built at the same time at Komsomolsk) were a little different to early boats _but_ they retained the tittle proekt 971. In the west were called Improved Akula...

    Begining with "Vepr" (entered in service in 1996) more improvements were made, so the west (NATO/US god knows who) decided to call it "Akula-II"...

    Then, Gepard, appeared in 2002, and nobody knows how to call it. Gepard is pretty different to Vepr (an Akula-II, improved over "Improved Akula", and much improved over "early Akula"), main difference, new Towed Array. Some sources in the west call them "Akula-III", some in Russia "Proekt 971M or Proekt 971B"...I don't know how they are called...

    THEN, we have two refurbished boats, one of them "Tigr" back into service and extesively upgraded...to wich level?, don't know...we could assume, some "Gepard technology" (mainly new TA maybe?, computing/display/sensors improvement?), and now is in overhaul "Pantera" an old "Improved Akula"...if those boats are different to "old" "Improved Akula", not being "Akula-II" (as Vepr), not being "Akula-III" (as Gepard)...what are they?...Akula-II improved?, Akula-II and half?, Akula-IV?...

    Remind that most russkie submarines being in overhaul last time returned with new goddeys. An old 667BDR that returned to service in 2003 (the K-433 "Svyatoy Georgiy Pobedonosets") showed a new Towed Array Sonar, very similar to that of "Gepard" (plausible due to time)...is very possible "K-114 Tula" refurbished 667BDRM finished this year would also show a new TA or more thingies...confusing boats?...really they're!!!...

  25. #55
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    Gatorfrey some nice pics for you:

    This is "your boat"

    Proekt 877V, the B-871 in service

    Now in docks



    Drawing


    Lovely boat, don't you think?

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    Ah,
    The infamous "second picture" I may have heard about. Not much extra detail,but interesting how they approach the design.
    I have two officers I have been writing,one for 3 years. Both served in the North Sea Fleet of Russian submarines. 25 and 30 years service. Learn a lot from those guys,plus the digging I do.
    Still, I feel there is much not being said about the pumpjet design and service by the Russians. Or, at least, I have found little on the subject.
    On the different Akulas,you are right. No two boats are the same as upgrades are constantly added. I have confirmed this with my source who oversaw upgrades.
    While the pumpjet thing is highly interesting to me, and I would like to hear anything anyone has out there on the Russian pumpjet, I have a new question.
    Delta IV.
    As I said earlier, I am involved with model submarines. There is a builder who wants to do a Delta IV hull kit in 1/96 scale. What we need is a station type cross section of a Delta IV and all external measurements etc, to shape the hull. I may not have called the stations diagram the right thing, but it should get across. Anybody have anything on this? The IV is a little harder to get information on than a III when you get up close and personal. Probably because they are still in use.
    Anybody help me here?
    I saw mention of the towed array change on the latest one. Is there a picture of this?

  27. #57
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    Hi Gatorfrey?

    It sounds nice about your contacts!, not everybody have these class of contacts for sure!...hope to hear sometime anything intersting you have heard and you can talk with us...

    About towed array change, are you referring to the K-433 "Svyatoy Georgiy Pobedonosets" of the proekt 667BDR? or to the K-114 "Tula" of the 667BDRM proekt?

    First, yes they're pictures about them (at the end), second, yes but no, they're pictures about refurbished "Tula" but no pictures showing the tail (like the ones of the K-433)...

    Look at these:
    http://deepstorm.v-real.ru/DeepStorm...-433/K-433.htm

    Sorry can't link from that page, recomended...not...HIGHLY redomended page about Soviet/Russian submarines.

    Regards

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    Pumpjet propulsion would be used if the Russians are convinced with the Test carried on either the Kilo or other subs , Its not if the Russians can deploy a pumpjet prop on their sub , But if they really see the advantage in deploying it.

    If the Russians test on subs using Pump Jet were sucessful and promising then we could see those technologies on Severdovinsk SSN and Borei SSBN , If not then we could still finds these future subs with Conventional 7 or 8 Blade Skewed Propeller.

    IIRC Jonesy was saying that at deeper depth the PumpJet are not as efficient as a conventional propeller.
    "A map does you no good if you don't know where you are"

  29. #59
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    Pumpjets may have significant disadvantages. Weight is the obvious one but how about nonacoustic vulnerability? Could wake sensors detect pumpjets easier than normal propellers because the density of water change is greater (RSM55 suggested kolos may measure this) due to water being locally compressed in a short tube versus dispersed laterally (sideways) by a normal propeller? In other words just as putting your finger on a hose produces a short high mass spray (akin to a pumpjet) would not a lower density flow of water by a normal propeller produce less wake in that the wake is wider and more diffuse (and harder to distinguish from natural variation) rather than a small but highly concentrated change in water density from the narrow focussed efflux of a pumpjet? Remember the F117 echewed a conventional circular nozzle because the heat efflux is concentrated and disperses slowly whereas the thin wide efflux of the platypus exhaust dissipated Ir energy faster by increasing the surface area of efflux to the atmosphere cooling it faster. Thoughts anyone?

  30. #60
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    It's easy to create a pumpjet, it's harder to create a silent one

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