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    PAK-FA, T-50: News #4

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    KomissarBojanchev

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    Re: PAK-FA, T-50: News #4

    Post  KomissarBojanchev on Tue Jul 24, 2018 12:32 am

    lol! lol! lol! lol! lol! lol! lol! lol!


    Russophobia at its finest
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    Militarov

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    Re: PAK-FA, T-50: News #4

    Post  Militarov on Tue Jul 24, 2018 12:42 am

    Pierre Sprey wrote:My take on the one famous pic that shows some engine face. Its just like the YF-23 which had better all aspect stealth than the F-22. The famous pic gives the illusion that you are looking head on and therefore looking straight at an engine. But in fact, you are not. Its on an angle. So you are looking down the nacle at an angle which you could also do on the YF-23 and spot some engine face.


    You are pushing it too far now with that Paint mastery.







    Reality is somewhere in the middle as usually.
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    miketheterrible

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    Re: PAK-FA, T-50: News #4

    Post  miketheterrible on Tue Jul 24, 2018 1:43 am

    They can black label Su-57 all they want. It wont stop it from being an awesome fighter jet.

    I am still eager to find out if any changes have been made to the AESA radar. All I know is that Rostec has been hard at work in making GaN modules (as I pointed out they are already in development) and have been producing very small, power efficient and heat efficient GaAS modules.
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    Pierre Sprey

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    Re: PAK-FA, T-50: News #4

    Post  Pierre Sprey on Tue Jul 24, 2018 1:58 am

    [quote="Militarov"]
    Pierre Sprey wrote:My take on the one famous pic that shows some engine face. Its just like the YF-23 which had better all aspect stealth than the F-22. The famous pic gives the illusion that you are looking head on and therefore looking straight at an engine. But in fact, you are not. Its on an angle. So you are looking down the nacle at an angle which you could also do on the YF-23 and spot some engine face.



    Reality is somewhere in the middle as usually.

    You keep posting these pics which add nothing. We already know that it doesn't have the clunky clumsy S duct setup that the F-22 has. The argument is if the engines are straight through like that pic alleges. They are not. They are offset


    But whatever. Turns out that the famous pic is a fake photoshop. Hence why there is no other pics showing engine face after 8 years.


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    Big_Gazza

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    Re: PAK-FA, T-50: News #4

    Post  Big_Gazza on Tue Jul 24, 2018 2:18 am

    Pierre Sprey wrote:But whatever. Turns out that the famous pic is a fake photoshop. Hence why there is no other pics showing engine face after 8 years.


    Well now, that IS interesting!  Very Happy

    I dare say however that our HATOstani Jihadist contingent will arrive any minute in a vain attempt at transforming reality with the force of their pronouncements...  kinda like the fuckstik who thought that 'shopping the intakes of a testbed PAK-FA will somehow result in the plane losing its stealthiness in the real world...
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    kvs

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    Re: PAK-FA, T-50: News #4

    Post  kvs on Tue Jul 24, 2018 2:51 am

    It is amusing how NATO fanboi retards don't even understand that the turbine blades do not offer a flat reflecting surface.
    Even when the engine turbine is spinning at its top RPM, to the EM photons it may as well be stopped. Of course, since it
    is spinning, progressive waves of photons will see the blades at different locations, but they will never form a sold disk and
    to each and every photon will off the slanted angle that you see.

    So bitching about the backscatter from the turbine face, compared to all the other surfaces, is simply ignorant blather.
    But as posted above, there is no straight line of sight to the engine face anyway. In other words, this is a complete
    and utter non-story.
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    kvs

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    Re: PAK-FA, T-50: News #4

    Post  kvs on Tue Jul 24, 2018 3:01 am

    Also, it is cute how there is never any quantification of the different design choices of the F-22 and Su-57 on their "stealth"
    cross section. By now there is enough information to build rudimentary 3D surface models of both jets. Run a freaking
    ray tracing program and determine the backscatter. Of course, the RAM properties are unknown, but such a simulation
    would stop all the retarded "debates" about S-ducts and round surfaces.

    It is patently obvious that Sukhoi would have higher level models which solve Maxwell's equations for their geometry. They
    can play around with RAM characteristics as well. NATO fanboi retards would have everyone believe that Sukhoi engineers
    can't even pick their noses correctly. Of course NATO fanbois are retards with severe mental inadequacies that result in
    over-compensation in the form of vicarious achievement and delusional fantasies.

    havok

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    Re: PAK-FA, T-50: News #4

    Post  havok on Tue Jul 24, 2018 12:34 pm

    kvs wrote:It is amusing how NATO fanboi retards don't even understand that the turbine blades do not offer a flat reflecting surface.
    Even when the engine turbine is spinning at its top RPM, to the EM photons it may as well be stopped.   Of course, since it
    is spinning, progressive waves of photons will see the blades at different locations, but they will never form a sold disk and
    to each and every photon will off the slanted angle that you see.  

    So bitching about the backscatter from the turbine face, compared to all the other surfaces, is simply ignorant blather.
    But as posted above, there is no straight line of sight to the engine face anyway.   In other words, this is a complete
    and utter non-story.
    It is called 'radar detection of agitated metals' (RADAM) and have been around for DECADES.

    https://www.researchgate.net/publication/234301847_Analysis_of_radar_detection_of_agitated_metals_RADAM
    It has been observed that the radar returns from moving multielement metal targets often exhibit an unexpected modulation that has both random (or noise-like) and semicoherent components. One possible mechanism for producing this effect is the modification of the current distribution on the target that results when electrical contacts between target elements are altered intermittently by the forces associated with target motion. Such intermittent-contact modulation must be considered in the design of a radar for detecting or identifying a target exhibiting this effect. Depending on the application, the observer may wish to enhance or suppress the observation of the effect, or it may be important that the effect itself be enhanced or suppressed in the object being observed. To accomplish any of these, the effect must be well understood, and we have therefore undertaken a program of research to study the radar detection of agitated metals (RADAM). This report summarizes our progress during the second year of the program. The overall objectives of our RADAM research program are to (1) identify and isolate the physical processes and mechanisms that contribute to a RADAM signature, (2) identify and explain important recognizable features of the signature, and (3) determine means for separating the significant identifying components of the signature from nonmeaningful components.
    The technique have been used to ID tracked vehicles on the ground.
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    kvs

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    Re: PAK-FA, T-50: News #4

    Post  kvs on Wed Jul 25, 2018 12:22 am

    havok wrote:
    kvs wrote:It is amusing how NATO fanboi retards don't even understand that the turbine blades do not offer a flat reflecting surface.
    Even when the engine turbine is spinning at its top RPM, to the EM photons it may as well be stopped.   Of course, since it
    is spinning, progressive waves of photons will see the blades at different locations, but they will never form a sold disk and
    to each and every photon will off the slanted angle that you see.  

    So bitching about the backscatter from the turbine face, compared to all the other surfaces, is simply ignorant blather.
    But as posted above, there is no straight line of sight to the engine face anyway.   In other words, this is a complete
    and utter non-story.
    It is called 'radar detection of agitated metals' (RADAM) and have been around for DECADES.

    https://www.researchgate.net/publication/234301847_Analysis_of_radar_detection_of_agitated_metals_RADAM
    It has been observed that the radar returns from moving multielement metal targets often exhibit an unexpected modulation that has both random (or noise-like) and semicoherent components. One possible mechanism for producing this effect is the modification of the current distribution on the target that results when electrical contacts between target elements are altered intermittently by the forces associated with target motion. Such intermittent-contact modulation must be considered in the design of a radar for detecting or identifying a target exhibiting this effect. Depending on the application, the observer may wish to enhance or suppress the observation of the effect, or it may be important that the effect itself be enhanced or suppressed in the object being observed. To accomplish any of these, the effect must be well understood, and we have therefore undertaken a program of research to study the radar detection of agitated metals (RADAM). This report summarizes our progress during the second year of the program. The overall objectives of our RADAM research program are to (1) identify and isolate the physical processes and mechanisms that contribute to a RADAM signature, (2) identify and explain important recognizable features of the signature, and (3) determine means for separating the significant identifying components of the signature from nonmeaningful components.
    The technique have been used to ID tracked vehicles on the ground.

    MAGNITUDE

    You ignore this key aspect by insinuating that the "flat face reflector" claim by the NATO fanboi retards is valid.
    They, and you are wrong. No shit Sherlock, there will be backscatter from the turbine blades. There
    will also by backscatter from any duct, even if its perfectly straight. A surface oriented at 45 degrees
    to a incoming photon has a non-zero probability scattering it back to where it originated, according to
    Quantum Mechanics.

    NATO fanboi retards have not been redeemed by your post.

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    GarryB

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    Re: PAK-FA, T-50: News #4

    Post  GarryB on Wed Jul 25, 2018 3:43 am

    I remember in the 1980s the US boasting that the radar on their AEGIS class cruisers were so amazing that they could count the engine blades of a target and identify the type of aircraft just from the radar return... I actually believed them at the time but then they shot down an iranian airbus...

    It was my understanding that the Su-57 was going to get blockers in the engine intakes... That could be as simple as two or three solid doors inside the air intake that open and cover more than half of the intake tube... the air could flow around them but there would be no direct line for radar waves to enter, let alone exit... and when radar stealth is no longer important the doors could close... giving a much better airflow than an S shaped tube could.

    But why would we assume the Russians know anything about Physics or design.

    havok

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    Re: PAK-FA, T-50: News #4

    Post  havok on Wed Jul 25, 2018 10:34 am

    kvs wrote:MAGNITUDE

    You ignore this key aspect by insinuating that the "flat face reflector" claim by the NATO fanboi retards is valid.
    They, and you are wrong.    No shit Sherlock, there will be backscatter from the turbine blades.   There
    will also by backscatter from any duct, even if its perfectly straight.    A surface oriented at 45 degrees
    to a incoming photon has a non-zero probability scattering it back to where it originated, according to
    Quantum Mechanics.  

    NATO fanboi retards have not been redeemed by your post.

    Redeemed? We are not wrong in order to 'redeem' anything. In fact, am willing to bet rubles to doughnuts that you did not know there is such a thing as RADAM algorithm.

    First...No one forced anyone to employ that S-duct technique to reduce overall RCS contribution. One can surmise that the reason the S-duct was employed because there is TECHNICAL validity to the argument that as a whole, the first turbine stage does constitute sufficiently a 'flat surface'.

    Second...In radar detection, patterns equals to detectability, and with fixed physical structures in a predictable motion, there WILL BE detection, or at the very least, contribution to the final RCS value. Backscatter signals, including edge diffractions, from the turbine blades will be contained and channeled by the intake ducts.

    No need to call in Sherlock.

    havok

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    Re: PAK-FA, T-50: News #4

    Post  havok on Wed Jul 25, 2018 10:38 am

    GarryB wrote:I remember in the 1980s the US boasting that the radar on their AEGIS class cruisers were so amazing that they could count the engine blades of a target and identify the type of aircraft just from the radar return...
    That is technically true and proven many times over...

    https://ieeexplore.ieee.org/document/8121117/


    GarryB wrote:I actually believed them at the time but then they shot down an iranian airbus...
    But only if the radar is looking directly at the engine, front or rear.

    GarryB wrote:But why would we assume the Russians know anything about Physics or design.
    We could assume the Russians knows a great deal. Too bad they ain't got the money to execute what they know.

    Face reality. The 57 is good design, only that it is not good enough.
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    GarryB

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    Re: PAK-FA, T-50: News #4

    Post  GarryB on Wed Jul 25, 2018 11:16 am

    That is technically true and proven many times over...

    So what you are saying is that the US AEGIS ships crew murdered those Iranians knowing full well it was an Airbus and not an F-14 which they suspected?

    That must be why the captain got that medal for bravery...

    But only if the radar is looking directly at the engine, front or rear.

    Even they would not have shot it down if it was heading away from them... or did they?

    We could assume the Russians knows a great deal. Too bad they ain't got the money to execute what they know.

    Of course... lets build an expensive 5th gen stealth fighter but not actually make it stealthy so we can save money on it...

    Actually that is not new... the mesh around the engines of the MiG-25 are made of silver and would have been slightly more efficient if they were made of gold.

    Large areas of the MiG-25 were made of stainless steel to save money too... except that at the time they were building entire submarines out of the stuff so you have to ask yourself how much money they actually saved...

    The steel could take the heat and was much easier to work with than Titanium, but it was heavy.

    There are plenty of cheap options to use to reduce radar signals through the air intakes... the MiG-29 already employs a solid engine intake blocker to protect from FOD material on the ground that would block all radar waves from the engine front... it also means the aircraft can operate from strips that don't have to be manually cleared of FO... even during war time... imagine them Russians doing something a different way from how America does it... how can they be so wrong?

    Face reality. The 57 is good design, only that it is not good enough.

    We already have our answer... US F-22s don't operate in airspace where there is S-400s, so it really is not a problem. Israel has F-35s and wont send them into Syrian airspace except hiding amongst US aircraft... a trick that could result in American aircraft being shot down... but then Israelis have never cared about that sort of thing in the past... USS Liberty... cough cough.
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    miketheterrible

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    Re: PAK-FA, T-50: News #4

    Post  miketheterrible on Wed Jul 25, 2018 12:27 pm

    Not good enough by who's standards? And not enough money? The Russians are pumping out trillions of Rubles for their defence purchases. Su-57 no exception.

    As a Russian general said "if US wants to test us, we can prove to them how stealthy their jets really are".
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    Singular_Transform

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    Re: PAK-FA, T-50: News #4

    Post  Singular_Transform on Wed Jul 25, 2018 12:49 pm

    [quote="havok"]
    GarryB wrote:

    Face reality. The 57 is good design, only that it is not good enough.

    Compared to what?

    They can decrease the X band cross section say by one more magnitude, with exploding manufacturing and maintenance cost, just to decrease the X band detection range by say 40%. At an age when the X band radar will not detect anything , but just control / communicate and illuminate.
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    GarryB

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    Re: PAK-FA, T-50: News #4

    Post  GarryB on Fri Jul 27, 2018 6:46 am

    It is a decision they had to make.

    100% stealth, which would make it orders of magnitude more expensive and also compromise other areas like making manufacturing and maintenance ,much more expensive and complicated too... and also effecting flight performance.

    Or they could scale back the stealth and make the aircraft more affordable domestically and for export (look at the shit exporting S-400s is producing... imagine what it will be like when Su-57Es are for export..) and have something they can build and use in useful numbers...

    BTW the Americans made a similar choice to supersede the F-14 and F-15... top speed requirements were relaxed to make the F-16 and F-18 cheaper to buy and to operate... an F-14 or F-15 would likely never reach their top speed operationally... it would require flying straight and level at medium altitude and burning a lot of fuel to get to mach 2.3+ and the fact is that neither aircraft could fly very far or for very long at such speeds... the canopies and other components couldn't take it.

    The MiG-25 and MiG-31 are made of special stuff to fly fast and for long periods.

    So if you are never going to operate at mach 2.4 in an F-16 then make the air intake lighter and simpler and limit it to mach 2, and the same for the F-18 at mach 1.8.

    Any enemy prepared to burn most of its fuel to accelerate to mach 2+ to get away will likely get a sidewinder up the ass for its trouble.

    Reducing the top speed means simpler engine intake, and also cheaper materials to be used for structure and components... and the aircraft is cheaper to operate and maintain... just like the choices the Russians have made with their new stealth fighter...

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