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    Su-57 Stealth Fighter: News #6

    magnumcromagnon
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    Post  magnumcromagnon Sun Dec 27, 2020 10:10 pm

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    Post  LMFS Sun Dec 27, 2020 10:12 pm

    Gomig-21 wrote:
    My dear LMFS, obviously you still care quite a bit because you answered and I appreciate that, despite how careful I was to write something I considered legitimate but tried my very best to walk eggshells (since I am 54 years old and have 0 interest in just coming out here and throwing spit balls; quite the opposite, actually since I have a personal vested interest in this aircraft) that it still is very difficult to actually speak in constructive criticism terms since it still pokes the Bear in a bad way which is in the least my intentions.  I understand, though.  I look at what I see and if it makes sense, I complement deservingly so and if it doesn't, I try to understand it first but if I base it on what I know (which isn't much admittedly so) then I will comment about it.  I don't throw mud and see if it sticks.  These are my observations.

    Hi Gomig-21, I answered because I know you are not a troll. Just try to understand that many of us have been dealing with a storm of fake, ill intentioned claims for years. And inevitably good intentioned people end up falling in the same logical traps laid for them, as Backman said in his post that I liked a lot. You see yourself debunking crap some propaganda platform creates, many of them probably on a a pay roll, just because you want people to be minimally informed and not badly mislead and manipulated. So excuse that I have little patience with certain arguments, it is not directed at you thumbsup

    I was actually complementing the timeframe and not critisizing it?  How is that possible?  I only said that many were influenced by the J-20 somewhat stealing the show in whatever way they did, details are unimportant but that was the point.  The influence of the J-20's appearance etc. influenced the way "many" thought of the PAK-FA/T-50/Su-57 development time.  That's all.
     

    I was adressing the argument itself, not attacking you, sorry if that was your impression. The development period of the Su-57 is IMO quite reasonable for what was achieved. The J-20 was somehow faster, but what is the result? It is a big question mark. The development times of US planes were way longer. I just wanted to make it clear that I don't think the Su-57 should be criticised in that regard. At least, not because of bad planing / negligence or lack of competence.

    Totally agree.  Does that mean we don't talk about it, to a certain level of understanding?

    Sure. I don't know the RCS level of a fastener applied like in modern LO designs at different frequencies and aspects, so there is little I can say, to be quite honest. I see them employed regularly on planes considered VLO, so their most common use as an argument against the Su-57 is moot for me. We need to stop talking as if we were all in the business of designing VLO planes in our spare time, clueless Western journos continuously talking BS about the issue have trivialized it to the point everyone thinks they know how stealth works... they do not. Even if we knew enough from a theoretical point of view (far from easy), we would still miss the hands-on experience and even if we had it, we would still need to know the secrets every manufacturer keeps for themselves. It is a very complicated topic.

    Yeah I wasn't referring to any of the dielectric panels or the radome color.  There's another panel just aft of the forward landing gear that is still in light blue and I thought there was something else too, just can't pinpoint it now and probably won't since I don't want to piss anyone off anymore than you guys already are.

    I cannot identify what panel you are referring to, there are some panels for small antennas in a clear grey colour but I cannot identify that blue one you mention.

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    Post  mnztr Sun Dec 27, 2020 10:18 pm

    magnumcromagnon wrote:Su-57 Stealth Fighter: News #6 - Page 39 EHtktybU4AkATnW?format=jpg&name=large

    Still a lot of pics with this plane emitting smoke, is Russian FADEC not as advanced as the west?
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    Post  mnztr Sun Dec 27, 2020 10:23 pm

    Backman wrote:


    How did the Bombardier C- Series program go ? It went bankrupt too and bailed out by the Canadian govt. And Airbus bought it for 50 cents/dollar. Program cost 7 billion.


    50 cents? More like 8 cents on the dollar, if that. It was a big win for Canada though as they now have a domestic major Airbus program
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    Post  kvs Sun Dec 27, 2020 10:39 pm

    The Bombardier C-series debacle was pure mafia extortion. The yanquis basically killed the little competition they had when
    Bombardier developed a good product. Thanks to the totalitarian level of thought control in Canada by the "free media" this
    was never a political issue. It should have been a scandal big enough to unseat the government.

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    Post  Backman Sun Dec 27, 2020 10:48 pm

    Su-57 Stealth Fighter: News #6 - Page 39 2257side_by_backspin321_deb670r-fullview.jpg?token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ1cm46YXBwOiIsImlzcyI6InVybjphcHA6Iiwib2JqIjpbW3siaGVpZ2h0IjoiPD01NjQiLCJwYXRoIjoiXC9mXC82NzMyZjYzZi1kNTRmLTQ3ODktYjRlYS1kZTRlMjEzMzJkOTZcL2RlYjY3MHItYWYxN2UyYzctYmNhOC00ZGFhLWI3MGYtOWJjMjdjYmNkMGRkLnBuZyIsIndpZHRoIjoiPD0xMjgwIn1dXSwiYXVkIjpbInVybjpzZXJ2aWNlOmltYWdlLm9wZXJhdGlvbnMiXX0

    Aircraft tend to have a seam, where the canopy meets the fuselage.


    Last edited by Backman on Sun Dec 27, 2020 10:53 pm; edited 1 time in total

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    Post  kvs Sun Dec 27, 2020 10:51 pm

    Sure. I don't know the RCS level of a fastener applied like in modern LO designs at different frequencies and aspects, so there is little I can say, to be quite honest. I see them employed regularly on planes considered VLO, so their most common use as an argument against the Su-57 is moot for me. We need to stop talking as if we were all in the business of designing VLO planes in our spare time, clueless Western journos continuously talking BS about the issue have trivialized it to the point everyone thinks they know how stealth works... they do not. Even if we knew enough from a theoretical point of view (far from easy), we would still miss the hands-on experience and even if we had it, we would still need to know the secrets every manufacturer keeps for themselves. It is a very complicated topic. wrote:

    Physics says that this "issue" is pure inanity. The size of objects matters to EM wave interaction with them. Even a high frequency signal
    is going to have a low scattering cross section for small objects. You simply cannot dial up the return signal by changing the frequency
    arbitrarily. There is a gain from using shorter wavelengths, but it saturates quickly. And higher frequency EM is attenuated more by
    atmospheric moisture and aerosols so it ain't no panacea.

    The rivet fags are ignorant twits who never got a proper education. They are internet fanbois fantasizing that they are engineer designers.
    That is why these Dunning-Kruger prats are always lecturing Sukhoi and all of Russia. These fanbois are cringeworthy losers.

    The radar blockers in the inlet ducts is another fanboi retard topic. Those Su-57 inlets are clearly stealth designs having the characteristic
    parallelogram shape with the added twist of inward curved lips that prevent direct line of sight inside the inlets for most angles of attack.
    So many losers over the last 10 years have been stroking their ignorant dicks over this subject. They always use some line of sight above
    the plane of the jet. Are NATzO radar systems deployed kilometers above the ground?



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    Post  kvs Sun Dec 27, 2020 10:58 pm

    I guess I forgot about the seam-tards. These clowns have no issue with the billboard sized rudders of the F-22 but try to
    nitpick over seams. Because they are just so proficient in physics and all of them have physics PhDs specializing in EM
    interactions with solid objects.

    You can also see the contradictory nature of all this Dunning-Kruger fanboi "analysis". They latch onto structural features
    as being important which implies that RAM is not enough. But when you have a massive side cross section in the F-22 all
    of the sudden RAM solves everything. If RAM was such a magic potion, then it would not matter what details your precious
    stealth wunderwaffe had.

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    Post  mnztr Sun Dec 27, 2020 11:14 pm

    Its possible the SU-57 design has optimized its radar stealth for a certain approach to the target, so stealth characteristics are not that important in certain areas of the plane.
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    Post  Isos Sun Dec 27, 2020 11:23 pm

    mnztr wrote:Its possible the SU-57 design has optimized its radar stealth for a certain approach to the target, so stealth characteristics are not that important in certain areas of the plane.

    Yes in the front.

    For a target going away from you radar the range will be reduced by more than half than when you look at it when it's coming at you. That's why you don't need a super stealth design from the back.

    The sides will always reflect more than the front because you always need wings and sides of the cockpit and engines are quite big and reflective.
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    Post  tanino Sun Dec 27, 2020 11:36 pm

    There are few openings and the rivets are smaller than expected. (f-22 more than 19 serrated flaps, F-35 I didn't count but it's a lot).

    How did they do it? Dieletectric welding? Good progress.

    Canopy edge, well done. (Compare with other photos of the prototypes and the KNAAPO promotional video in the prototype hangar.

    The work on the stealth grids is simply brilliant. What's new? The VLO design of the cannon grip. Nice work.

    RAM well laid out, probably two layers of non-linear moss-crossed nanotubes.

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    Post  mnztr Sun Dec 27, 2020 11:48 pm

    kvs wrote:The Bombardier C-series debacle was pure mafia extortion.   The yanquis basically killed the little competition they had when
    Bombardier developed a good product.   Thanks to the totalitarian level of thought control in Canada by the "free media" this
    was never a political issue.  It should have been a scandal big enough to unseat the government.  

     

    Yes it was but Boeing ended up **uking themselves royally in the end. Airbus got a 7B program for 700m as well as a massive manufacturing complex within the NAFTA zone with the full protection of the EU and within the Canada-EU free trade zone. A 7B  corp loss is not that big in Canada. Canada sucked up the loss and gave a nice sweet win to Boeings #1 competitor. It was a major loss for Boeing even before the 737 MAX scandal exploded in their face.

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    Post  marcellogo Mon Dec 28, 2020 3:08 am

    Hole wrote:Su-57 Stealth Fighter: News #6 - Page 39 Eqpt7u10
    Some differences. This is not from me, I just found it.

    Quite minimal, I would dare to say, also because we are looking to the fifth prototype.

    They have added some extra equipment and closed down a lateral exhaust and modified the rudders connection to the roof.
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    Post  GarryB Mon Dec 28, 2020 3:28 am

    By invisible I think Garry means transplant to radar wave.

    Dielectric panels as used for side mounted radars and nose radomes need to be radar transparent in the frequencies the radar antenna behind them operate in otherwise they would block the radar signals in both directions rendering the radar antenna useless.

    Such panels often get different special paint applied to them and certainly would not get RAM coatings as this would reduce the performance of the radar antenna too.

    The development period of the Su-57 is IMO quite reasonable for what was achieved. The J-20 was somehow faster, but what is the result? It is a big question mark. The development times of US planes were way longer. I just wanted to make it clear that I don't think the Su-57 should be criticised in that regard. At least, not because of bad planing / negligence or lack of competence.

    It is pretty obvious that the Chinese aircraft are based on other designs, while the Russian plane is a unique shape that needed to be properly tested and developed presumably from a range of different shape alternatives.

    Considering the US is a super power that prints its own money and spends ten times more on defence than Russia does and has a world wide network of allies/puppet states all keen to help support their projects I would think Russia developing a 5th gen fighter would be some sort of miracle over any time period... especially considering Europe couldn't do the same either. Pretty good for a third world gas station.

    Sure. I don't know the RCS level of a fastener applied like in modern LO designs at different frequencies and aspects, so there is little I can say, to be quite honest. I see them employed regularly on planes considered VLO, so their most common use as an argument against the Su-57 is moot for me.

    I am old enough to remember western experts complaining about the fit and finish of MiG-29s... whining about gaps between plates and raised fasteners upsetting the aerodynamics... except that was bullshit too... having a perfectly smooth surface is actually bad for aerodynamics... in the same sense that a smooth golf ball has higher drag than the same sized and same weighted one with dimples on its surface.

    Of course in those days RCS was not really a consideration because without proper shaping and carrying external weapons few aircraft were low observable... there was just no point.


    Still a lot of pics with this plane emitting smoke, is Russian FADEC not as advanced as the west?

    Lots of sophisticated western jets emit smoke too, but these are Al-41s, which are essentially upgraded Al-31s rather than the new gen engines they intended for this aircraft.
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    Post  TMA1 Mon Dec 28, 2020 3:44 am

    mnztr wrote:
    magnumcromagnon wrote:Su-57 Stealth Fighter: News #6 - Page 39 EHtktybU4AkATnW?format=jpg&name=large

    Still a lot of pics with this plane emitting smoke, is Russian FADEC not as advanced as the west?

    nah western fighters give off similar smoke. note it's color. I believe the fuel is nitrogenized.

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    Post  Backman Mon Dec 28, 2020 7:21 am

    mnztr wrote:
    magnumcromagnon wrote:Su-57 Stealth Fighter: News #6 - Page 39 EHtktybU4AkATnW?format=jpg&name=large

    Still a lot of pics with this plane emitting smoke, is Russian FADEC not as advanced as the west?

    I am unsure what the camera setting is, that gives pics this overly glossy look where you can see into the surface. But it seems to be the new thing in photography that is getting around everywhere. I seen a F-35 and J-20 with this camera setting and it looked similar. I am trying to find that pic. A photographer on Twitter named vlad vlad has it

    The smoke has something to do with this as well imo. Nitrided kerosene gives yellow-brown smoke on afterburn. Like the tu 160 orange smoke

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    Post  kvs Mon Dec 28, 2020 9:41 am

    All jet engines burning hydrocarbon fuels generate NOx (NO and NO2). Recall that N2 accounts for 80% of air. NO2 has the a
    characteristic reddish brown colour which looks like brown "smoke" coming out of the nozzles. Also, every jet engine emits
    precursors to aerosols and thus leaves a plume of very small particulate that nucleates instead of being emitted directly fully
    formed.

    If you look carefully at the photograph there is no white (opaque) smoke component even though it looks like there is. This
    photo also shows clear evidence of editing in the straight line discontinuity running through the wing tip to the left. There
    is no evidence of any inferior combustion in Russian jet engines and people who think there is can go and get stuffed. In
    fact, the blue glow coming out of the nozzles of Tu-23s and other Russian jets indicates it the combustion is higher temperature
    which makes it automatically more efficient since jet engines are heat engines. This higher temperature combustion will produce
    more NOx.

    This topic is yet another attempt to engage ludicrous medieval "wisdom" to discuss Russian subjects. I suppose that western
    "experts" excrete shit that does not smell.

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    Post  LMFS Mon Dec 28, 2020 1:03 pm

    All engines emit smoke when throttle settings are changed, and typically when AB is engaged/ disengaged. You can see this in any airshow by F-22 or F-35, they are no different to Su-57 in how much smoke they produce, only they are Western products and therefore beyond any doubt or any questioning clown

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    Post  Sujoy Mon Dec 28, 2020 2:14 pm

    GarryB wrote:It is pretty obvious that the Chinese aircraft are based on other designs, while the Russian plane is a unique shape that needed to be properly tested and developed presumably from a range of different shape alternatives.
    The US decided to introduce stealth aircraft using the pretext that they are invisible to ground based radar.

    However, given how extensive the Soviet Union's satellite network was, it was quite easy for the USSR's satellites to detect stealth aircraft. A constellation of 30 plus satellites in low earth orbit can both detect and track stealth aircraft.

    With the cost of spacecraft launch decreasing every year more and more countries are now placing satellites in low earth orbit. Therefore, US and Chinese stealth aircraft like the F-35, F-22, J-20 can easily be detected from space.
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    Post  Daniel_Admassu Mon Dec 28, 2020 2:37 pm

    Sujoy wrote:
    GarryB wrote:It is pretty obvious that the Chinese aircraft are based on other designs, while the Russian plane is a unique shape that needed to be properly tested and developed presumably from a range of different shape alternatives.
    The US decided to introduce stealth aircraft using the pretext that they are invisible to ground based radar.

    However, given how extensive the Soviet Union's satellite network was, it was quite easy for the USSR's satellites to detect stealth aircraft. A constellation of 30 plus satellites in low earth orbit can both detect and track stealth aircraft.

    With the cost of spacecraft launch decreasing every year more and more countries are now placing satellites in low earth orbit. Therefore, US and Chinese stealth aircraft like the F-35, F-22, J-20 can easily be detected from space.

    Now what does this mean? I don't think satellites are better placed for stealth detection than ground based assets.
    For one, low earth orbit satellites that circle earth at 600 - 1000 km altitude need to fly fast so as not to fall to the ground. That gives them a few precious minutes to observe anything and thus are next to useless for tracking an airplane. Even if you have 30 or so such satellites in orbit it is practically impossible to coordinate their orbits to be able to track an arbitrarily headed supersonic jet.
    For another, radar stealth detection is about multiple band reflection and coordination of data, not about line of sight as you seem to refer to.
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    Post  TMA1 Mon Dec 28, 2020 2:45 pm

    Daniel_Admassu wrote:
    Sujoy wrote:
    GarryB wrote:It is pretty obvious that the Chinese aircraft are based on other designs, while the Russian plane is a unique shape that needed to be properly tested and developed presumably from a range of different shape alternatives.
    The US decided to introduce stealth aircraft using the pretext that they are invisible to ground based radar.

    However, given how extensive the Soviet Union's satellite network was, it was quite easy for the USSR's satellites to detect stealth aircraft. A constellation of 30 plus satellites in low earth orbit can both detect and track stealth aircraft.

    With the cost of spacecraft launch decreasing every year more and more countries are now placing satellites in low earth orbit. Therefore, US and Chinese stealth aircraft like the F-35, F-22, J-20 can easily be detected from space.

    Now what does this mean? I don't think satellites are better placed for stealth detection than ground based assets.
    For one, low earth orbit satellites that circle earth at 600 - 1000 km altitude need to fly fast so as not to fall to the ground. That gives them a few precious minutes to observe anything and thus are next to useless for tracking an airplane. Even if you have 30 or so such satellites in orbit it is practically impossible to coordinate their orbits to be able to track an arbitrarily headed supersonic jet.
    For another, radar stealth detection is about multiple band reflection and coordination of data, not about line of sight as you seem to refer to.

    hmmm I bet satellites are getting to the point of detecting even aircraft in real time. stealth aircraft have a much bigger RC from the top, and these satellites probably have multispectral sensors which aren't just focusing on a certain frequency.
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    Post  LMFS Mon Dec 28, 2020 7:17 pm

    I once proposed the following configuration for MRAAMs in the Su-57's bays, of course dismissed by some -supposedly- very knowledgeable Western gentlemen:

    Su-57 Stealth Fighter: News #6 - Page 39 4_mraa11

    Well, this is the next iteration of the J-20, apparently from an official AVIC model:

    Su-57 Stealth Fighter: News #6 - Page 39 Ep1PqNoVoAETo8-?format=jpg&name=large

    I see no fundamental difference in clearances and missile layout between both models, as it is and was obvious the manufacturers have every reason to reduce the wingspan and therefore dimensions required by internally carried weapons and this will be improved step by step in the next years until optimum packaging is reached. This is IMHO a good reason for the lack of information about both the weapons developed for the Su-57 and the layout of the bays.

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    Post  kvs Mon Dec 28, 2020 7:30 pm

    LEO satellites do not have the density of coverage to be able to track effectively and on demand. They are also moving relative to the
    surface fast enough to take them out of range after a short period of time. One LEO orbit is typically under 90 minutes (however,
    they can be over two hours depending on the geometry). Geostationary satellites that are ideal for continuous monitoring have the
    problem of being at 35,786 km from the surface which is 5.6 Earth radii. That is a serious limiter on high resolution imaging.

    Multi-spectral detection on satellites is to be expected. So the concept of tracking in real time is feasible with enough coverage
    density. The US is using commercial Trojan Horse projects to achieve this. Starlink is clearly a dual use system. Even though
    the Keyhole satellites are the size of a bus, they are old designs. I suspect that modern CCDs have evolved enough that a full sized
    telescope optical layout is not necessary to get high resolution images. Unlike observations of remote stars, the photon flux
    from the surface of the Earth is high enough that ultra-focusing is not required.
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    Post  Isos Mon Dec 28, 2020 8:18 pm

    If it was possible to put 4 missiles inside the bays they would so. And we still don't know the dimension of r-77M which is different than r-77-1.
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    Post  mnztr Mon Dec 28, 2020 8:29 pm

    Isos wrote:
    mnztr wrote:Its possible the SU-57 design has optimized its radar stealth for a certain approach to the target, so stealth characteristics are not that important in certain areas of the plane.

    Yes in the front.

    For a target going away from you radar the range will be reduced by more than half than when you look at it when it's coming at you. That's why you don't need a super stealth design from the back.

    The sides will always reflect more than the front because you always need wings and sides of the cockpit and engines are quite big and reflective.

    More then from the front maybe from the front and from a higher altitude. This way they can press their advantage of higher altitude capability over F-35 and have more energy in their long range missiles when they shoot.

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