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    Tu-160 "White Swan"

    GarryB
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    Post  GarryB on Sun Apr 26, 2020 11:40 am

    Composite materials are not some super material with no problems of their own.

    Composites can have all sorts of problems including de-lamination and the fact that they suddenly snap without warning.

    Being able to flex in one direction or another might be useful, but it also might not... I would guess a centre box section holding the mechanism for the wing sweep is something that needs to be very strong and relatively light.

    If the original design in that regard works I don't see any reason to change it except to replace it with a more sophisticated fixed design that offers lift for takeoff and landing from reasonably sized runways but also low drag for high speed flight.

    The Tu-160 is a big plane that already had composite materials in its design so improving those and also adding more should be a good thing but remember these things need to operate in arctic bases, so don't ruin the design.
    kvs
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    Post  kvs on Sun Apr 26, 2020 3:34 pm

    GarryB wrote:Composite materials are not some super material with no problems of their own.

    Composites can have all sorts of problems including de-lamination and the fact that they suddenly snap without warning.

    Being able to flex in one direction or another might be useful, but it also might not... I would guess a centre box section holding the mechanism for the wing sweep is something that needs to be very strong and relatively light.

    If the original design in that regard works I don't see any reason to change it except to replace it with a more sophisticated fixed design that offers lift for takeoff and landing from reasonably sized runways but also low drag for high speed flight.

    The Tu-160 is a big plane that already had composite materials in its design so improving those and also adding more should be a good thing but remember these things need to operate in arctic bases, so don't ruin the design.

    The box section experiences load distortions more complicated than any wing or fin. It is the juncture of the body and the wings so has
    at least twice the number of bending and shear modes, and on top of that the full load of the wings and the body is riding on it. Showing off
    with composites in this critical part is asking for trouble.

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    Post  mnztr on Sun Apr 26, 2020 4:35 pm

    GarryB wrote:Composite materials are not some super material with no problems of their own.

    Composites can have all sorts of problems including de-lamination and the fact that they suddenly snap without warning.

    Being able to flex in one direction or another might be useful, but it also might not... I would guess a centre box section holding the mechanism for the wing sweep is something that needs to be very strong and relatively light.

    If the original design in that regard works I don't see any reason to change it except to replace it with a more sophisticated fixed design that offers lift for takeoff and landing from reasonably sized runways but also low drag for high speed flight.

    The Tu-160 is a big plane that already had composite materials in its design so improving those and also adding more should be a good thing but remember these things need to operate in arctic bases, so don't ruin the design.

    This plane was designed 70's, every load bearing structure must flex, if not it will shatter. Cold is not a problem for composites are they have been used for decades on planes that take off in 40C and operate at -40C. If they had the wing box tooling available, I would agree, just build it. But since they don't and have to fully reconsider this structure, for 3 units a year composites, may offer an opportunity, or Al Li, or a combination of composites, alumunim and steel. Even steel has vastly improved in 40 years. Point is, replicating the old structure is just as, or maybe even more complex then just designing a new one from a clean sheet with the 40 years of additional knowledge they have.
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    Post  GarryB on Mon Apr 27, 2020 5:50 am

    Showing off
    with composites in this critical part is asking for trouble.

    My thoughts exactly.

    If they want to be super modern and ground breaking then creating a wing design that does not need to sweep to allow takeoffs from reasonable length runways, but also high dash speeds would be much more impressive...

    There haven't been that many changes in wing design... taken to the very core... the straight wing of WWII like the Yak-3 subsonic planes was standard, with sweeping it back of the wing necessary as speeds approached the speed of sound as with the MiG-15 and 17. The MiG-19 achieved supersonic speed with a straight swept wing but with an extreme sweep which increased takeoff and landing speeds so the delta wing and tail surfaces of the MiG-21 tried to mix reasonable runway length with supersonic speed with a shorter runway... then they went for exotic solutions like solid rocket boosters to shorten takeoff run and of course lift jets for STOL and VSTOL, and at the same time swing wings. The swing wings prevailed but were not the ideal solution, which came in the form of the MiG-29/Su-27 wing and lifting body shape to allow short take off and landing with supersonic speeds.

    In bombers they went from swing wing back to subsonic in the flying wing design...

    Cold is not a problem for composites are they have been used for decades on planes that take off in 40C and operate at -40C.

    Not all parts of an aircraft are subjected to outside temperatures in flight... the fact that the F-35 has problems operating in the cold in Japan suggests that operating in the Arctic at much much lower temperatures would be a serious problem...

    I understand the west is happy to build enormous air conditioned and heated hangars for their planes... the Germans keep their tanks in tents to prevent them getting too cold too, but that is just not practical in Russia. They might be building the hangars but there are times when the aircraft will spend time sitting outside for whatever reason so they have to be able to take it.

    If they had the wing box tooling available, I would agree, just build it. But since they don't and have to fully reconsider this structure, for 3 units a year composites, may offer an opportunity, or Al Li, or a combination of composites, alumunim and steel.

    They have built a new factory to make Tu-160s from scratch which includes a forge to make the titanium centre structure. I would expect a forge that size will be able to be used to wield other materials as well... the justification for building it was because they are going to build another 50 odd Tu-160s and such a forge could also be used in the construction of the PAK DA as well... and I suspect a new MiG-41 might benefit from one piece large section Ti structures being formed in one piece...

    Even steel has vastly improved in 40 years. Point is, replicating the old structure is just as, or maybe even more complex then just designing a new one from a clean sheet with the 40 years of additional knowledge they have.

    Obviously they will revise the design.... if they didn't it would have been in mass production 5 years ago, but they needed to digitise the design and then upgrade it... they did it the way they did everything else... upgrade existing bits as far as possible while working on a major upgrade... and in the back ground work on the from scratch replacement... ie T-72 upgrades, T-90AM, and T-14.

    Except with the White Swan you end up with Tu-160M, Tu-160M2, and PAK DA.
    d_taddei2
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    Post  d_taddei2 on Fri May 08, 2020 7:48 pm

    going through my photos and found this. the Tu-134UBL a Tu-160 crew training version, with Tu-160 nose cone, although i always found that the nose cone of the tu-22 and tu-160 vermy similar, and due to the size of the Tu-134 to me it looks more like a variant of the Tu-22 or vice versa.

    Tu-160 "White Swan" - Page 34 Dsc03816
    GarryB
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    Post  GarryB on Sat May 09, 2020 8:58 am

    When they talked about upgrades for their big bombers they often mentioned unification of as much as possible.

    Part of that would include radar and engines, though that was only to replace the NK-25 in the Backfire with the NK-32 of the White Swan to improve commonality across the types... I don't remember reading about any plans for the NK-32 to be used on the Bear or anything....

    They did talk about the self defence avionics suite and radar and weapons being unified though...
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    Post  magnumcromagnon on Mon Jun 29, 2020 3:15 pm

    Tu-160 "White Swan" - Page 34 Ef02d420474a26f1592994292

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    mnztr

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    Post  mnztr on Tue Jun 30, 2020 3:35 pm

    magnumcromagnon wrote:Tu-160 "White Swan" - Page 34 Ef02d420474a26f1592994292

    Still the most beautiful angel of amageddon out there.
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    Post  JohninMK on Sat Jul 04, 2020 1:39 pm

    Tu-160 "White Swan" - Page 34 EcCY94CWsAAwbEr?format=jpg&name=large

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    Big_Gazza
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    Post  Big_Gazza on Thu Jul 09, 2020 11:50 am

    Links to a veritable treasure trove of Tu-160 info and photos, 551 pages in total Shocked (unfortunately in Russian but still their is plenty for mono-lingual types like me).

    http://www.aviationunion.ru/Files/Nom_2_TU_1.pdf
    http://www.aviationunion.ru/Files/Nom_2_TU_2.pdf

    thumbsup

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    Post  LMFS on Thu Jul 09, 2020 1:03 pm

    Big_Gazza wrote:Links to a veritable treasure trove of Tu-160 info and photos, 551 pages in total  Shocked  (unfortunately in Russian but still their is plenty for mono-lingual types like me).

    http://www.aviationunion.ru/Files/Nom_2_TU_1.pdf
    http://www.aviationunion.ru/Files/Nom_2_TU_2.pdf

    thumbsup

    That book is incredible indeed respekt
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    Post  LMFS on Fri Aug 28, 2020 8:06 pm

    UAC about the new Tu-160M

    https://zen.yandex.ru/media/id/5ddfbc8b9515ee00ac9e370a/belyi-lebed-letit-v-buduscee-5f4903d61a067118d6299e0e
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    Post  Tsavo Lion on Thu Sep 03, 2020 7:26 pm

    Chinese praise the Tu-160: https://rg.ru/2020/09/03/kitajskoe-izdanie-nazvalo-bombardirovshchik-tu-160-hudshim-koshmarom-nato.html
    kvs
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    Post  kvs on Mon Sep 07, 2020 3:26 am



    The Kuznetsov NK-32 engine production capability was almost lost thanks to Yeltsin's comprador regime. One of the key reasons it was saved was that it was used
    for the development of a gas turbine to propel LNG fuel locomotives.

    The NK-32 has a hybrid design that is not a run of the mill jet engine. The wikipedia page on it is idiotic. Turbofans are not designed to operate at 20 km but the NK-32
    can operate at such an altitude.

    It looks like a derivative of the NK-32 will be used to re-engine An-124 cargo aircraft now that Motor Sich has been run into the ground by Banderatards and their NATzO
    patrons.

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    magnumcromagnon
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    Post  magnumcromagnon on Mon Sep 07, 2020 3:54 am

    kvs wrote:

    The Kuznetsov NK-32 engine production capability was almost lost thanks to Yeltsin's comprador regime.   One of the key reasons it was saved was that it was used
    for the development of a gas turbine to propel LNG fuel locomotives.  

    The NK-32 has a hybrid design that is not a run of the mill jet engine.   The wikipedia page on it is idiotic.   Turbofans are not designed to operate at 20 km but the NK-32
    can operate at such an altitude.  

    It looks like a derivative of the NK-32 will be used to re-engine An-124 cargo aircraft now that Motor Sich has been run into the ground by Banderatards and their NATzO
    patrons.  

    Originally, but the PD-35 will likely supersede it in replacing the Motor Sich engines in the An-124 fleets. Will likely supersede them in the PAK-DA's, unless they decide to make them supersonic with thrust-vectoring down the road.
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    Post  LMFS on Mon Sep 07, 2020 4:13 am

    magnumcromagnon wrote:Originally, but the PD-35 will likely supersede it in replacing the Motor Sich engines in the An-124 fleets. Will likely supersede them in the PAK-DA's, unless they decide to make them supersonic with thrust-vectoring down the road.

    The text (at least translated) is misleading, the idea is to create a high-bypass engine based on the NK-32, since its gas generator already has the needed size. PD-35 is way bigger.
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    Post  kvs on Mon Sep 07, 2020 4:30 am

    I found the comment about some derivative being used for the An-124 a bit strange and people here have filled in the details. The D-18T does not resemble
    the NK-32 in any fashion and any replacement for it would be starting from scratch. The PD-35 is supposed be based on a scalable design and would be
    a high bypass turbofan so it make sense to use it instead of an NK-32 derivative.
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    Post  GarryB on Mon Sep 07, 2020 9:28 am

    The thing is that re-engining the An-124 is to basically replace the Orc engines... they don't need to be super powerful or super efficient... they just need to offer the right level of power and be Russian.

    In the long term the PD-35 is actually too powerful... remember the Ukrainian engines being replaced are about 23 ton thrust engines, so replacing four 23 ton thrust engines with a total of 92 tons thrust, with either two PD-35s with 70 tons of thrust or four PD-35s with 140 tons of thrust does not balance... it will either be under powered or over powered.

    Keep in mind that the 6 engined An-225 has 138 tons thrust so actually using four PD-35s on the An-225 would be a good plan as it reduces weight and complication by removing two engines but retains the thrust of all 6...

    The NK-32 of the Blackjack has a dry thrust of something like 14 tons and full AB thrust of 25 tons... using AB on a transport simply does not make sense but it is a low bypass turbofan engine... so essentially changing the front fans to make them 2-3 times bigger means the rear hot turbojet section sucking through vastly more cold air would dramatically increase thrust but would reduce the exhaust velocity... in other words the thrust might be 25 tons thrust without afterburner but the engines would now be way to wide to fit inside a Blackjack and certainly would render the aircraft subsonic only even if they could be adapted to fit.

    Essentially what they might be talking about is using the hot section of the NK-32 to drive a high bypass turbofan to get a quick simple 24-25 ton thrust non afterburning high bypass jet engine... wont have amazing performance but should be good enough to replace the Ukrainian engines.

    They wont need to use it on anything else... it could be kept on An-124s and exported to other operators of the aircraft that also now can't get Ukrainian engine parts...

    When the PD-35 is ready and other models like a PD-24 or whatever is needed they can put it on Slon and Il-106 type transports that will essentially eventually replace the An-22 and An-124 in Russian service... the replacement engines could be made for export too to support operators of the An-124 as well...

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    Rodion_Romanovic
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    Post  Rodion_Romanovic on Mon Sep 07, 2020 10:10 am

    kvs wrote:I found the comment about some derivative being used for the An-124 a bit strange and people here have filled in the details.     The D-18T does not resemble
    the NK-32 in any fashion and any replacement for it would be starting from scratch.     The PD-35 is supposed be based on a scalable design and would be
    a high bypass turbofan so it make sense to use it instead of an NK-32 derivative.  

    The An-124 (and probably also the new il-106) needs an engine with about 23-24 tons of takeoff thrust (but it could benefits of a bit more thrust, and in the past motor sich proposed a D18T modification with 25-26 tons of takeoff thrust).

    The PD35 will  not be ready before at least 6 years and even if it is a scalable design the PD24 will be less of a priority, and will be available later. (They need anyway to design and test a new engine, even if they could save a bit of time by reusing the solutions from its smaller (PD14) and bigger brother PD35).

    Concerning the NK32 derived engine, as it was mentioned in another thread, it should be in development already since several years ago and a variant of it should go on the Pak-Da subsonic bomber).
    In a few articles from last year and from early 2020 also it was mentioned that such engine should start ground tests around the last quarter of 2020...

    Another NK32 derived engine, called NK-23D should also be in development (or was proposed) and it is not clear how much commonality there is between this one and the Pak-Da engine.
    It wouldn't need to be started from scratch anyway.

    At least,  not the whole of the engine...

    Well, if the core (in this case  IP and HP compressor, Combustor, and HP and IP turbine) is of the acceptable size, they need to probably upgrade a bit the materials and some minor redesign (to get some increase of operating temperatures for the HP compressor and turbine) and  probably some changes to the combustor as well.
    A few stages must be added to the LP turbine (since it operates at a lower speed, having a bigger fan, and maybe also there they could introduce some new lighter materials (like intermetallic ti-al for LP turbine blades, probably already considered also for PD14 and PD35).

    The fan needs of course to be completely new, going from a multi stage very low bypass fan (needed for supersonic speed) of the NK32 to a large single stage fan (maybe a scaled up version of the PD14 fan, if perm motors and Kutznetov exchange information)...

    The only strange information (dated 2015) available in internet mentioned that, since they wanted to keep the same nacelle of the D18T, they will end up compromising the design and limiting the Bypass to a value of about 5,5 to1, the same as the old D18T, and with a specific fuel consumption slightly worse than the old D18T... but that does not make sense...unless we are talking about a solution that can be ready in a relatively short time and it is just a placeholder...

    https://www.litmir.me/br/?b=547394&p=9

    Anton Shatskiy, Deputy General Designer of OJSC Kuznetsov, said at a conference at CIAM that a unique turbine that can withstand long-term high-temperature conditions provides the NK-32 gas generator with a parametric and design reserve for creating a line of high-thrust turbojet engines on its basis for use on transport and passenger aircraft. The first in their series could be the NK-23D three-shaft by-pass turbojet engine with a thrust of 24 tf for the remotorization of the An-124 Ruslan heavy military transport aircraft.

    According to Anton Shatskiy, “the task is to raise the An-124 aircraft with domestic engines in 2019,” but “if we are now talking about creating a scientific and technical reserve, carrying out research and development work,” then the creation of a new engine of this class may take 10 -15 years. Therefore, Kuznetsov offers an alternative solution - to make an engine for Ruslan with the maximum use of the already existing reserve for the NK-32 gas generator. At the same time, serious conditions are set for the engine specialists: “We must fit exactly into the dimensions of the D-18T nacelle, the nacelle must remain in the same length, approximately in the same mass, i.e. we have both geometric and constructive constraints, ”said Kuznetsov’s deputy general designer. Nevertheless, he believes that it is quite possible to meet such a tight deadline.


    According to the presentation presented at the conference in CIAM, the NK-23D proposed for remotorization of Ruslans with a takeoff thrust of 24 tf (for the D-18T - 23.4 tf) will have a degree in cruise mode (height 11 km, M = 0.75) bypass 5.4 (for D-18T - 5.5) and specific fuel consumption 0.565 kg / (kgf • h) with a thrust of 5000 kgf. According to the official data of Motor Sich PJSC, the thrust and specific fuel consumption of the D-18T series 3 in cruising mode in the same conditions is 4860 kgf and 0.546 kg / (kgf • h).



    Here it is not clear if this engine (NK23D)  will be related to the similar thrust engine in development for the Pak-Da or not....


    It would be smarter to redesign the nacelle and allow the advantages of a higher bypass... in that case however this will mean that it will not be able to mount them in the existing an124 withoout modifying the pylons and the mounts as well...


    By the way, if I am not mistaken Kuznetov has in the not so remote past, already did a comparable operation (but smaller in scale), when they improved the D30 engine with a bigger fan to increase a bit the bypass.

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    Post  Rodion_Romanovic on Mon Sep 07, 2020 11:51 am

    In another source they mentioned about a cruise SFC 0.570 lb/(lbf*h) for the D18T.

    Unfortunately there are not many modern engine of this size with which to compare (only the Trent500 introduced in 1999), but if we take the latest generation, the best among the engine for narrow body airliners (takeoff thrust around 12-15 tons) have a cruise SFC of about 0,52 lb/(lbf*h) (for comparison the PS-90A has an SFC of about 0.595 lb/(lbf*h) and the IAE V2500 (western engine contemporary to the PS90) has a SFC of around 0,58 lb/(lbf*h).

    If we go on the larger size, like the engine for the larger airbus and Boeing widebodies, with more than 40tons of takeoff thrust, we can find cruise SFC of around 0,48 lb/(lbf*h) .

    If we interpolate we can imagine that an optimised latest generation high bypass turbofan for civilian use with a takeoff thrust of around 24 tons should end up having a cruise SFC between 0,5 and 0,51 lb/(lbf*h)

    note

    You have to compare cruise sfc (specific fuel consumption) if an engine with cruise SFC of another engine.

    Sometimes takeoff SFC is reported instead, but if you do not pay attention the values could be misleading. Even if fuel consumption is much higher at sea level than at cruise altitude, the SFC is dependent on thrust, and the takeoff thrust is normally around 4 to 5 times bigger than the thrust at cruise level (the main reason is the higher air density at sea level).

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    Post  kvs on Mon Sep 07, 2020 2:24 pm

    The PAK-DA will be a high altitude aircraft like the Tu-160. So an NK-32 derivative engine makes total sense. It makes no sense for the An-124 which requires a high bypass turbofan without
    any high altitude operational mode. As I posted the PD-35 is a target size of a whole class of engines that will include smaller thrust variants. Since the PD-14 is already certified, the "PD-35"
    class is not that far off in the future so will overlap any re-engine need for An-124s. I just don't see how the NK-32 is a shorter path to a D18-T replacement, it will have to have every turbine and
    "fan" stage totally redesigned.

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    Post  Rodion_Romanovic on Mon Sep 07, 2020 4:00 pm

    kvs wrote:The PAK-DA will be a high altitude aircraft like the Tu-160.   So an NK-32 derivative engine makes total sense.   It makes no sense for the An-124 which requires a high bypass turbofan without
    any high altitude operational mode.    As I posted the PD-35 is a target size of a whole class of engines that will include smaller thrust variants.     Since the PD-14 is already certified, the "PD-35"
    class is not that far off in the future so will overlap any re-engine need for An-124s.   I just don't see how the NK-32 is a shorter path to a D18-T replacement, it will have to have every turbine and
    "fan" stage totally redesigned.



    Not every turbine, probably it would be alright to keep HP and IP turbine (and also IP and HP compressor), especially if they already improved them for the new version of the NK32.

    It needs for sure a new fan and they must change the LP turbine paired with it (possibly they can keep what is already there and just add 2 or 3 stages at the end.

    As far as the combustion chamber, I do not know if it copes with the latest civilian regulations about emissions and noise.

    Such derivative engines are nothing strange or new.
    The Olympus engine of the Concorde has been modified to create both an industrial engine and a ship gas turbine, and also Kuznetov has experience with industrial gas turbine derivatives.

    As I wrote above, a few years ago (in the early 2000s) they also did a similar thing with the D30, increasing the thrust  and the bypass ratio (from 2.2 to 3.65).
    For the NK32 the changes would be more, but not unfeasible.

    The results in term of SFC and emissions will not be on par with a fully modern engine, but it can be available soon (especially if they actually worked on it).

    The PD24 variant of the PD35 will be available maybe 3 to 4 years after the PD35 will be introduced in service, so we are talking about 2030 at least.

    By the way, UAC is considering some some additional development  of MC21 by 2035.

    These would be the larger variants
    MC-21-500 and 600, with engines with a takeoff thrust of about 20-25 tons.
    And this would consist in the development of the PD24 engine by that time.

    Back into the engine modification topic, here some info on the D-30 modernisation

    wikipedia wrote:
    D-30KP-3 "Burlak"  is a turbofan engine deeply modernized in the 2000s at NPO Saturn. It features a new fan, more than 1.5 times the bypass ratio, increased thrust by 1 ton, fuel consumption is reduced by 11%. Complies with the standards of the fourth chapter of ICAO on noise and emission of harmful substances.


    https://vpk.name/news/56492_nelegkie_na_podem.html


    Engine problem

    Nikolay Boltenkov believes that the Il-76 has only one problem - the D30-KP engine, which does not meet the ICAO emission and noise requirements. According to him, NPO Saturn has developed and successfully tested the deeply modernized D-30KP-2 engine, called the D-30KP-3 Burlak. "The result is a very interesting engine for us, which meets the standards of the fourth chapter of ICAO on noise and emission of harmful substances. The thrust increased by 1 ton, fuel consumption decreased by 11%, it was supposed to double the assigned resource," said Mr. Boltenkov. Nikolay Boltenkov considers the installation of Perm engines PS-90A-76 on his IL-76TD, which has worked out half of the calendar resource, "economically unjustified", since this requires a rather serious modernization of the aircraft, associated with the replacement of pylons and linking the engine with the rest of the onboard systems. Burlak, similar in design to the IL-76 D-30KP, does not require this, and the cost of remotorization of existing aircraft is acceptable for the operator.

    In this regard, Mr. Boltenkov regrets that the United Engine Corporation (UEC) has not yet included Burlak in its production line, although Aviakon was ready to act as a launch customer for NPO Saturn and confirmed its need for 40-43 engines of this type. However, according to experts, the position of the UEC is quite understandable from the point of view of the economics of engine manufacturers. "It is much more efficient to concentrate production on the production of modern PS-90s, which in the future will account for hundreds of units, than to open a line for the remotorization of an aging aircraft fleet," says Oleg Panteleev, head of the AviaPort analytical service.




    https://www.aviaport.ru/digest/2005/04/08/89761.html


    D-30-KP-3 "BURLAK" - A HIGHLY EFFECTIVE SOLUTION FOR THE MODERNIZATION OF THE POWER PLANT OF THE IL-76 AIRCRAFT AND ITS MODIFICATIONS

    Source:  PJSC" UEC - Saturn " "
    Published: 08.04.2005 ,

    The Il-76 transport aircraft can be confidently called one of the most successful aircraft of its class in the history of world aviation. It is still one of the most demanded cargo aircraft and forms the basis of the transport aviation fleet in Russia and a number of other countries.

    In modern conditions, the operation of the IL-76 is carried out in two large segments: commercial cargo transportation and transport operations of government services and departments. In total, 491 Il 76 aircraft are currently in operation in Russia, more than 300 - abroad. Most of them (about 70%) have been in operation for 10-15 years, that is, they have approached or are approaching the second half of their life cycle.

    The solution to the problem of the "low-budget" modernization of the Il-76 aircraft, which are in the second half of their life cycle, is designed to ensure the program of re-motorization of the Il-76 with D-30KP Burlak engines being implemented by NPO Saturn. The main task solved within the framework of this program is to expand the range of capabilities and increase the life cycle of most of the Il-76 family aircraft fleet (Il-76TD transport aircraft, Il-76MD military transport aircraft, Il-78 tanker aircraft, A- 50) by upgrading the base engine of the Il-76 family - D-30KP, serially produced by NPO Saturn.

    The modernization consists in replacing the 3-stage low-pressure compressor with a single-stage fan and increasing the bypass ratio from 2.2 in the base engine to 3.65 in the D-30KP "Burlak". The use of a highly efficient low-noise fan combined with an increase in the bypass ratio will reduce the specific fuel consumption in the engine by about 10%, increase the resource and ensure its compliance with ICAO Chapter 4 noise and emission standards.

    NPO Saturn has been working on the D-30KP Burlak program since mid-2003. At present, the first stage of bench tests has been completed, based on the general results of which a typical engine design for certification tests will be determined. Engine certification is scheduled for Q1 2007. Work with IL OJSC on linking the engine to the IL-76 aircraft is in the active phase: a technical task has been formed, the aircraft flight characteristics have been determined, the installation of engines on the aircraft and an investment project for the remotorization of the IL-76 fleet are being worked out. Technological preparation of production was carried out at NPO Saturn, and the technology of manufacturing fan blades was tested.

    We can say with absolute confidence that the main technical tasks of modernization have been solved, in particular, improving operational characteristics, increasing engine resource and increasing its efficiency, ensuring modern and promising environmental characteristics.

    The technical assignment for the design of the D-30KP "Burlak" was aimed at increasing the engine thrust from 12,000 to 13,000 kg. As a result of bench tests, this figure was not only achieved, but also exceeded, reaching almost 14,000 kg. With subsequent fine-tuning, this indicator will become the norm. This will increase the takeoff weight of the aircraft to 195 tons, take off from a shorter runway, and maintain takeoff thrust at a higher ambient temperature (up to +30 degrees Celsius).

    The design features of the D-30KP "Burlak" allow, by reducing the temperature in front of the turbine by 40 degrees, to increase the service life of the hot part of the engine and the engine as a whole, significantly increasing the overhaul and assigned resources, calendar service life.

    D-30KP "Burlak" allows to reduce specific fuel consumption from 0.71 to 0.64 kg / kg h, which allows saving up to 18%. fuel per hour. This leads to an increase in flight range or an increase in payload.

    Aircraft equipped with D-30KP Burlak engines will fully comply with all modern ICAO requirements for emissions of harmful substances and noise levels on the ground, which will allow them to freely perform air transportation outside Russia after 2006.

    The cost of remotorization of Il-76 aircraft and its modifications with D-30KP Burlak engines is 3.5 times lower in comparison with PS-90A. The cost of remotorization is the most important indicator of the economic efficiency of modernization and is considered as the sum of the costs of installing engines on an aircraft and their further operation. The low cost is due to the high degree of unification (75%) of the D-30KP "Burlak" with the base engine D-30KP-2, and the modification of the engine during the overhaul will further reduce the cost of re-engining the aircraft as a whole. In addition, the creation of a new infrastructure for servicing the engine and aircraft in operation is not required.

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    GarryB
    GarryB

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    Post  GarryB on Tue Sep 08, 2020 8:02 am

    The An-124 (and probably also the new il-106) needs an engine with about 23-24 tons of takeoff thrust (but it could benefits of a bit more thrust, and in the past motor sich proposed a D18T modification with 25-26 tons of takeoff thrust).

    It depends on what they want for the Il-106... if they want it to be a four engined aircraft and they end up putting the same engine in it that they then put in the An-124 they they are shooting themselves in the foot.

    The real value of the An-22 over the An-124 was not that 80 tons is a better capacity than 120 tons... the value was that its engines and propellers were more efficient so it was cheaper to use.

    If the An-22 had the same engines as the An-124 it would not be cheaper to use... it could use shorter runways and would probably accelerate much better but costing the same would mean often it would make more sense to just put a 150% An-22 load into an An-124 and just use less planes.

    There are a couple of ways the Il-106 could be cheaper than an upgraded An-124 with 24 ton thrust engines... using two more powerful engines (ie PD-35s) or using the same number of less powerful but more fuel efficient engines (something like a PD-22... which is still rather more powerful than the 14 ton thrust engines in the Il-76 at 40 ton payloads and 16 ton thrust engines in the Il-76 at 60 ton payloads)

    The idea behind the PD-35 is that it is going to be the top end of a scaleable family of engines with modern designs and made from modern materials... that should be able to be produced without a lot of extra testing and a brand new from scratch design would need.

    The PD35 will not be ready before at least 6 years and even if it is a scalable design the PD24 will be less of a priority, and will be available later.

    If they can solve the current problem of the new Russian engines for the An-124 then the problems with Slon and Il-106 are not urgent and can be solved in good time.

    Right now it is the An-12 and An-24/6 and An-72 and An-2 and light transports that are more urgent in terms of needing replacement as the airframes are starting to expire...

    They need anyway to design and test a new engine, even if they could save a bit of time by reusing the solutions from its smaller (PD14) and bigger brother PD35).

    See that is where I disagree... the Slon is going to be a 160-180 ton capacity aircraft and the Il-106 is going to be an 90-110 ton capacity aircraft between the current 60 ton Il-476 and An-124 at 120/150 ton depending on the variant.

    There was talk of using inflight refuelling on the Il-106 and therefore increasing the payload capacity and extending flight range... which means most jobs done by the An-124 would now be done by the smaller cheaper aircraft and the bigger jobs the An-124 did will be done with the Slon...

    Essentially the An-124 would get replacement engines and then work for the remainder of their airframe lives and then be retired and replaced by fully Russian aircraft.

    Concerning the NK32 derived engine, as it was mentioned in another thread, it should be in development already since several years ago and a variant of it should go on the Pak-Da subsonic bomber).

    Yes, the issue is that for a flying wing there is not a lot of internal volume for an enormous high bypass turbofan engine, while on the big transport planes that could also use it there is plenty of room, so much of the work done on the engine to make it suitable for a high subsonic flying wing but fitted internally could be used for the version for the An-124 to bide its remaining time in service, while the full sized full power 35 ton thrust version called PD-35 could be developed from that with a bigger fan no longer constrained by needing to be internal... to be used in 4-5 years time on Slon and Il-106... four engines and two engines respectively perhaps...

    Another NK32 derived engine, called NK-23D should also be in development (or was proposed) and it is not clear how much commonality there is between this one and the Pak-Da engine.
    It wouldn't need to be started from scratch anyway.

    Perhaps the number is the hint... maybe the NK-23D is the NK-32 with a higher bypass ratio and no afterburner for use on the An-124 to replace the Ukrainian engines... perhaps including an afterburner for the PAK DA for takeoffs and rapid climbs... (it would not need to go supersonic as that would be problematic but not impossible.... the main issue is power to weight ratio needed for sustained supersonic flight requires slim low drag design, which is the opposite of what a strategic bomber wants with max fuel and max internal weapon payload...)

    The fan needs of course to be completely new, going from a multi stage very low bypass fan (needed for supersonic speed) of the NK32 to a large single stage fan (maybe a scaled up version of the PD14 fan, if perm motors and Kutznetov exchange information)...

    I am sure they know what they are doing... Smile

    The only strange information (dated 2015) available in internet mentioned that, since they wanted to keep the same nacelle of the D18T, they will end up compromising the design and limiting the Bypass to a value of about 5,5 to1, the same as the old D18T, and with a specific fuel consumption slightly worse than the old D18T... but that does not make sense...unless we are talking about a solution that can be ready in a relatively short time and it is just a placeholder...

    Depends who is running or paying for the programme... if it is the military then they wont care about fuel consumption... they have x number of planes each needing 4 new engines... if they can keep the costs down they wont care about the fuel consumption difference... if fuel consumption was a primary concern then wait for a better engine to be delivered instead and get the full benefit of a new design...

    Worst case scenario they could have one of those external bladed fans that for a time were considered to be the way of the future... you can't get much more bypass than that... Smile

    and specific fuel consumption 0.565 kg / (kgf • h) with a thrust of 5000 kgf. According to the official data of Motor Sich PJSC, the thrust and specific fuel consumption of the D-18T series 3 in cruising mode in the same conditions is 4860 kgf and 0.546 kg / (kgf • h).

    So in cruising mode the new engine will create a total of 20 tons thrust, while the old engines would generate 19.44 tons thrust.

    0.565kgf per hour at 20 tons thrust is 11.3 tons of fuel per hour, while 0.546kgf per hour at 19.44 tons of thrust is 10.6 tons per hour... but with the extra thrust the aircraft with the new engines and old nacelles should be flying faster, which will reduce flight time and get you to where you were going faster.

    If the pilot with the new engines wanted to fly at the same speed and throttled back to 4860kgf per hour the difference in fuel consumption at the same thrust with the same engine covers so therefore at the same speed would be 10.98 tons per hour which is less than 300 kgs of fuel difference... considering the Ukrainian engine is no longer available and there are no spares that can be bought for it from anywhere I would say burning an extra 300 kgs of fuel an hour is not really a big deal... they will be replacing them in time anyway...

    It would be smarter to redesign the nacelle and allow the advantages of a higher bypass... in that case however this will mean that it will not be able to mount them in the existing an124 withoout modifying the pylons and the mounts as well...

    300kgs of fuel is about 300 litres... you are going to have to burn a lot of fuel before a redesign becomes profitable for the Russians... and keep in mind while I say they can export the engine to existing users, Ukraine will likely go after them for violating the terms of their contracts by letting Russians work on Ukrainian owned designs... it wouldn't matter for Russian planes because they pretty much make all the other parts so the Orcs can go suck on a lemon, but if you are an international company and they threaten to invalidate your warranties and block your supply of spare parts if you let the Russians touch the planes then it is more of a problem... and they don't care.... it is not like they are doing anything else like making engines or planes... they have lots of time on their hands.

    By the way, if I am not mistaken Kuznetov has in the not so remote past, already did a comparable operation (but smaller in scale), when they improved the D30 engine with a bigger fan to increase a bit the bypass.

    The PS-90A family of engines I think... the first two made with US help but III model Russian parts.

    As I wrote above, a few years ago (in the early 2000s) they also did a similar thing with the D30, increasing the thrust and the bypass ratio (from 2.2 to 3.65).

    Ahh, yes, now I remember... after the PS-90A engine was ready it was realised that a 6 million dollar new engine that burned less fuel than the D-30 was hard to justify... with four engines per aircraft that is a 24 million dollar bill for just one set of new engines when the originals cost about 600K each... 2.4 million dollars for original engines vs 24 million for new ones... 21 million dollars buys you a lot of fuel vouchers to cover the price difference.

    The real issue was noise and pollution emissions so they made an upgraded D-30 with better fuel efficiency that met the new requirements... I don't think it was much more powerful.... still only about 14 tons thrust but in cruise they operate at about 2 tons thrust anyway so it is not a big deal... for the new engine the price went up to 800K per engine... not as sophisticated or state of the art, but for most airlines and users much more practical...


    The results in term of SFC and emissions will not be on par with a fully modern engine, but it can be available soon (especially if they actually worked on it).

    This is a factor... if it is only for Russian military transports then noise and emission regulations don't apply.

    D-30KP-3 "Burlak"

    That is the one... didn't realise it had a 1 ton thrust increase...




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    mnztr

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    Post  mnztr on Fri Sep 11, 2020 5:45 am

    GarryB wrote:The thing is that re-engining the An-124 is to basically replace the Orc engines... they don't need to be super powerful or super efficient... they just need to offer the right level of power and be Russian.

    In the long term the PD-35 is actually too powerful... remember the Ukrainian engines being replaced are about 23 ton thrust engines, so replacing four 23 ton thrust engines with a total of 92 tons thrust, with either two PD-35s with 70 tons of thrust or four PD-35s with 140 tons of thrust does not balance... it will either be under powered or over powered.

    Keep in mind that the 6 engined An-225 has 138 tons thrust so actually using four PD-35s on the An-225 would be a good plan as it reduces weight and complication by removing two engines but retains the thrust of all 6...

    The NK-32 of the Blackjack has a dry thrust of something like 14 tons and full AB thrust of 25 tons... using AB on a transport simply does not make sense but it is a low bypass turbofan engine... so essentially changing the front fans to make them 2-3 times bigger means the rear hot turbojet section sucking through vastly more cold air would dramatically increase thrust but would reduce the exhaust velocity... in other words the thrust might be 25 tons thrust without afterburner but the engines would now be way to wide to fit inside a Blackjack and certainly would render the aircraft subsonic only even if they could be adapted to fit.

    Essentially what they might be talking about is using the hot section of the NK-32 to drive a high bypass turbofan to get a quick simple 24-25 ton thrust non afterburning high bypass jet engine... wont have amazing performance but should be good enough to replace the Ukrainian engines.

    They wont need to use it on anything else... it could be kept on An-124s and exported to other operators of the aircraft that also now can't get Ukrainian engine parts...

    When the PD-35 is ready and other models like a PD-24 or whatever is needed they can put it on Slon and Il-106 type transports that will essentially eventually replace the An-22 and An-124 in Russian service... the replacement engines could be made for export too to support operators of the An-124 as well...

    You can't just take a 4 engine plane and convert it to a 2 engine or a 6 to a 4 It will require wholesale reengineering of the entire wing to the point of not being economic. you want to have something close to the same power range around 10-15% + is useful.
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    Post  mnztr on Fri Sep 11, 2020 5:51 am

    Military definitly cares about fuel consumption for airlifters. It changes the range/payload capability significantly especially for Russia which does not have a global fleet of refuelling planes.

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