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Possible J-XX pic?

I can only commend on this part.The most diffcult thing of 5th generation fighter desigen is to make a balance between steath,maneuver and supersonic ability.It depends on what the PLAAF wants from the J20.I personally think the PLAAF will put the super maneuver ability ahead of steath,the final one will be the supersonic.So sometimes you need to sacrify some steath ability to get a more super manever fighter.
And personally I dont think we need to discuss something on an unproving picture.I think it should take at least two years that we could get the offical leaking J20 pictures.It is there,but we wont see it untile the PLAAF wants to leak.

I have the faith that China will make the most balanced next gen fighter. :china:
 
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3. the shape of the wings. It looks pleasantly surprising to me if it were the real one - at least it would shut mouthes of those who smear it as no more than another straight copy of Raptor. Yet, maybe Gambit can answer this one, aren't those curled back wings with all their extra angles/curve lines attracting more RCS, intutively at least to my untrained eyes, when being radared from the rear? It seems to me that RCS from the back of the wings is so different ( not sure a good or bad thing) from other standard straight wing forms from the back angle like those of F-22 for example ).


I think rather than deliberately curled back a piece of it has been cut away from what would have been a delta like wing because the cut away piece coupled with the V-tails causes radar energy to be reflected back.
 
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That pic in the first post seems pretty real to me. Especially when you compare it to the actual Google Earth image of the runway in question.
 
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3. the shape of the wings. It looks pleasantly surprising to me if it were the real one - at least it would shut mouthes of those who smear it as no more than another straight copy of Raptor. Yet, maybe Gambit can answer this one, aren't those curled back wings with all their extra angles/curve lines attracting more RCS, intutively at least to my untrained eyes, when being radared from the rear? It seems to me that RCS from the back of the wings is so different ( not sure a good or bad thing) from other standard straight wing forms from the back angle like those of F-22 for example ).
Not 'attract' but create. There are many things to consider but for a non-RAM body, the three main items regarding the seeking radar signals are:

- Direction of approach
- Angle of approach (or angle of incident)

The third item is the edge diffraction effect and a brief explanation of it is here => http://www.defence.pk/forums/1337224-post30.html

Because the aircraft would be most likely heading towards the seeking radar's position, most wing designs that has RCS reduction in mind must focus on trailing edge diffraction effects. There is not much we can do for the leading edge due to aerodynamic necessities. So if the trailing edge is not properly designed and shaped, the edge diffraction effect can be a major contributor to the overall RCS value. The B-2 is a flying wing design so in order to minimize -- not eliminated -- the edge diffraction effect, the wing's trailing edge is 'saw-toothed'. This pattern is most prominent on the F-117 and less so for the F-22 and F-35. Because currently we cannot completely eliminate the edge diffraction effect, we must redirect its travel direction to be away from the seeking radar's position.

So the answer to your question is that we do not know. These fanboy art pieces do nothing to ease the understanding of basic radar detection principles, let alone the complexity of RCS modeling, prediction, and measurement. But they do contribute to a lot of fantastic claims that many ended up defying the laws of physics.
 
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The RCS is measured by the microwave tools throúgh experiments,so far there is no such a mathmatic model could acturally caculate a plans RCS which mens you can not know its RCS by look or caculation.Who comments on a plans RCS by look ís either a super smart or super fool.
There is no single equation, ala grand unified theory in physics, for RCS modeling, prediction, and measurement. But there are four KNOWN mathematical theories that form the foundation of RCS modeling, prediction, and measurement. Being 'known' meaning they are not state secret by any government but that they are in public domain.

- Radar range
- Edge diffraction
- Surface wave behavior
- Wave superposition

What is state secret is the 'how' when they are exploited in complex relationships to each other in order to work with complex bodies.

Remember...The Russian mathematician Pyotr Ufimtsev was the one who formalized the maths governing edge diffraction, which is only one part of RCS modeling, prediction, and measurement. The behavior of EM signals upon a body was already well known, just that no one was smart enough to mathematically formalize those behaviors. Until Ufimtsev took the time to do it. The Soviet government, in a monumental blunder, dismissed his work as having no military value, allowed his work to be published in the public domain, where it remained obscure until Lockheed engineers got their hands on it. So just because something is in the public domain, that does not mean it is well known. It may be known to some, but not known to some who are missing something in their work.

Lockheed used Ufimtsev's work to model, predict, and finally measured a shape that, even without the 'invisible' hyperbole, was in practice quite 'invisible' to radar, even for today. But the shape could not fly...

Lockheed F-117 Nighthawk - Wikipedia, the free encyclopedia
The F-117 was born after combat experience in the Vietnam War when increasingly sophisticated Soviet surface-to-air missiles (SAMs) downed heavy bomber flights.[12] It was a black project, an ultra-secret program for much of its life, until the late 1980s.[13] The project began in 1975 with a model called the "Hopeless Diamond"...

F-117 History
The model was mounted on a 12-foot high pole, and the radar dish zeroed in from about 1,500 feet away. The site radar operator could not see the model on the radar, until a black bird landed right on top of the Hopeless Diamond. The radar was only picking up the bird....
But in order to make the body flyable, Lockheed must begin to compromise some of that ultra low RCS value. Radars detect birds more by their hard beaks than by their soft bodies. A bird's feather layers are natural RAM that is par with today's manmade RAM.

Rich called on Bill Schroeder, a Lockheed mathematician, and Denys Overholser, a computer scientist, to exploit Ufimtsev's work. They designed a computer program called Echo, which made it possible to design an airplane with flat panels, called facets, which were arranged so as to scatter over 99% of a radar's signal energy "painting" the aircraft.
Basically...Every time an engineer from a subsystem make a modification of his area of expertise, say something like the pitot probe for air data such as airspeed and altitude, the entire virtual aircraft must be plugged back into Echo where the effect of the change is modeled, predicted, and measured to see if the change increased the overall RCS above a specific tolerance. The greater the body, and a wing is much larger than a pitot probe, the longer the re-modeling, prediction, and verification. The work was tedious and keep in mind that this was in the mid-1970s where no engineers below the supervisory level has discretionary access to something called a 'computer'. The final result was the F-117.
 
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H-8 Bomber Prototype

chinesestealthcraft.jpg


Xian H-8 bomber was a Chinese military aircraft, successor to the aging twin-engined H-6 jet bomber.

That's the MiG-31 Foxhound, designed and built by Hollywood.
 
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That's not the foxhound!!! If my sci-fi knowledge is correct I am pretty sure that this is a X-302 from stargate SG-1.

If that's the case, then it's ancient technology compared to the other things in Stargate.
 
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H-8 Bomber Prototype

chinesestealthcraft.jpg


Xian H-8 bomber was a Chinese military aircraft, successor to the aging twin-engined H-6 jet bomber.

HAHAHHA. pic is from Stargate SG-1 :D OMG! It's fraking TV-show.:rofl:

Just to be clear,it's F-302
 
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