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Its Official: JXX is going to test fly in the next few days

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This coming from an elite member? Wow... Guess what? FGFA involves India so I guess that's a fail... Un-oh...

It will fail... expect critical design flaws... The Russians have always been angry about India's inability to keep its end of the bargin. And you guys' "over-ability."

Though, the WS-10A is yet to enter service after 8 years of testing. What will be the fate of Kaveri?
 
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It will fail... expect critical design flaws... The Russians have always been angry about India's inability to keep its end of the bargin. And you guys' "over-ability."

Though, the WS-10A is yet to enter service after 8 years of testing. What will be the fate of Kaveri?

Cheers for your kind words, and I certainly hope the engine went through 8 years, otherwise, your sources will have fooled you again, just like all the other speculative crap you posted before based on the J-XX etc.
 
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Unless, of course, you take preliminary technical literatures as technical bibles.
Why should I not? Once again, we can only wonder what would motivate people to make claims that are contrary to the laws of physics. Let us take a look at this claim...

Diffraction is not the same thing as reflection, and the diffracted signal, by definition of diffraction, cannot travel back toward the source. If anything, I'd think that diffraction can only help with regard to stealth for the very same reason.
Whose definition are we seeing here that say a diffraction field, unless physically blocked, cannot return to source direction? Where is the TECHNICAL source to support this claim? I have presented at least two sources that said otherwise.

The behavior of a diffraction field occurs on all surfaces on an aircraft, but the issue here is the location of a flight control surface that may, or may not, be detrimental to the goal of low RCS. The canards themselves move, but the wings do not, only the trailing edges of the wings move. And by virtue of the canards' being the foremost moving bodies on a larger complex body, the potential for the canards to be the greater, if not greatest, contributor to the overall RCS is very real. Nowhere have I said that the JXX's canards will or will not be detrimental, but what the readers have seen so far are Chinese fanboys' attempts to violate the laws of physics, as shown, to make it 'will not'. At least when I present my criticisms, I am honest to say that we are uncertain at this time.
 
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One query. what does the 'xx' in Jxx denote? Is it a simply a space holder/variable for unknown number, like in algebra? Some number will replace the'xx' in future?
Roman numeral XX = 20 in decimal. So is Jxx = J-20??
 
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If there is a god of radar physics, he must be laughing his guts out when he read the nonsense about bi-static radar operation from you. Anyway...What the hell does this...'inhomogeity of the medium'...mean? The 'medium' here is air, or rather relatively 'empty space'. A bi-static configuration exploits the greater forward scatter signals. So by your argument here...the inhomogeity of the medium...whatever the hell that mean...make a bi-static configuration inefficient, then that would make the mono-static configuration completely worthless. And yet mono-static radars are prevalent. As I have pointed out before and will repeat, in theory, a bi-static configuration is low observable aircrafts' best detector precisely because of those forward scatter signals. So in trying to prove me wrong about canards, you just ended up calling bi-static radars worthless against 'stealth'. Am beginning to suspect that these are not your words but someone else's that you are trying to pass off as your own. There seems to be no technical consistency.


That is why bi-static radars are no panacea to 'stealth' despite what some chinese fanboys would like believe whenever they tried to downplay the F-22. This is not because bi-static sensor systems, like the Kolchuga or Silent Sentry, do not work but because a bi-static configuration is inherently structurally intensive, requiring physically distinct transmitter and receiver stations.


Meaningless drivel. The point I am making is that diffraction energy in a contributor to a body's total RCS. So far you have yet to show the readers a source that says otherwise.


Sandwich? When a fighter launches a semi-active radar guided missile, we have an airborne bi-static configuration.

homing.jpg


The parent aircraft illuminated the target, the missile is the receiver and its position is an offset from the parent's position, thereby creating a 'bi-static triangle'...

Bistatic radar noncooperative illumination synchronization techniques

When we have data link capability, the transmitter aircraft is one leg of that triangle, the target is another leg, and the receiver aircraft is the final leg. It does not matter if there is one or ten receiver aircrafts, for each receiver there is only one bi-static triangle. That mean we can have ten bi-static triangles from one transmitter. The receivers do not have to be directly opposite of the transmitter. Forward scatter does not mean literally straight forward but can be angular as the signal is deflected off the target. If anything, the ideal bi-static position is when the transmitter-target-receiver triangle is like below...

bi-static_sys.jpg


...But since airborne targets are in motion we know this is not possible. A bi-static configuration can exploit diffraction or deflection or both. So once again your ignorance and pretense is exposed.


More like made up 'facts' and 'truths'. But hey...Since when is a communist an honest person?

The JXX is supposedly equipped with canards. Naturally the question would be if canards are detrimental to its RCS reduction. I presented arguments and sources that say leading and trailing edges produces diffraction fields that are detrimental to RCS reduction.

RCS Pylons | Antenna Measurement Solutions


:rofl:

As I always find: too many people are just too much letting themselves entangled with trivial details but forget the essences of principles. Those people include federal employees, defense expertise, national lab leaders, and even some university professors... Frankly, I’m fed up with those fools. And I don’t understand why you make such a simple thing so complex, provided that you want to fool the credulous.

a) any inhomogeneity of the media will cause EM wave to going in a bent way (roughly speaking).

Canards do introduce the inhomogeneity in general.

If you have any language problems because of your upbringings, from EM point of view, just let you know that dialectic property can be described with permittivity and permeability of the medium, including vacuum. In general they are the function of space (x,y,z) and EM frequencies. If they are constants in terms of space (x,y,z), they are spatially homogenous. If EM wave travels within such a homogenous medium, no scattering, and thus, loosely speaking, no diffraction/reflection will happen.

Why I say it loosely speaking? Because any other phenomena (reflection, diffraction, etc.) are part of scattering. Reflection is specular scattering, diffraction is interference among (in general) forward scattering waves. Diffusion is non-specular scattering. Strictly speaking, when waves move to next position in a medium, it is a result of diffraction (or interference) of all waves from their previous position(s). Thus, we can say all earlier waves are “primary sources” of next waves, and next waves are “secondary sources” to yet the third waves. This is how the “snapshots” are when we strictly and correctly visualized the EM propagation.

If you have a sense of quantum mechanics, those perturbations (inhomogeneity ) to the medium function like potential wells that cause waves to scatter (reflection/scattering/diffraction, what ever you name it.)


b) In general, direct reflection (specular part) contains the majority of the energy, unless the surface/interface where the wave encountered is very rough. Rough or not is compared with the wavelength. If the size of “humps” or “dents” are comparable with the EM wavelength it is rough. Thus for longer wavelength, a surface usually looks more smooth.

Physically, it is very easy to understand, as specular part of the energy comes as zero-th order approximation from Born Approximation. Any diffuse scattering are in higher order.

This is perhaps why the first order correction for stealth, in general, should be geometrical to deflect the specular part of the energy. Even it will introduce aerodynamic instability, the cost is still comparatively low.

If specular energy is absent due to absorption or deflection or strong diffusion, people may then consider higher order approximations.

Even according you, diffractive energy goes off the front canards and happens(!) to be caught by the wings, yes it serves as a signal, but still 1) in general diffracted energy is weak compared with specular energy, 2) second reflection will make it even weaker. 3) the weak signal may well be intermittent or fortuitous due to the precise match of the paths. Above talk is in absence of specular part.

c) RAM still may/may not substantially diminishes diffraction, depending on the physical nature/structure of the material and the shining wavelength. Moreover, if only leading edges are RAM coated, it helps but perhaps still not enough as multiple scattering may hit somewhere other than the leading edge!


“An airfoil is conducive to surface traveling waves, which do not lose energy as it traverse the wing's surface.” :lol:

Man, you are so reckless! Hahahaha, the mere “conductive” can sustain a traveling wave to stay forever. Gee, you are the person to get fa(ke)sics Nobel Prize soon, as you are in open defiant of energy conservation!

Just for your EM abc, check out formula (8.12) in Chapter 8 of J.D. Jackson&#8217;s <Classical Electrodynamics>, 2nd Edition, published by John Wiley & Sons 1975:
Energy of surface wave dissipated in a unit area da in a conductor is dP(loss)/da = [1/(4pi)](nu_e*omega*delta/4)(H_parallel)^2, where delta is inversely proportional to sqrt(conductivity) (formula 8.8 of the same chapter)

Unless your airplane has wings of superconductor, :rofl: the delta will never be zero as the conductivity is always finite and the wave energy will ALWAYS diminish in the skin of surface.

For non-conductive composite materials, this phenomenon normally may not even exist.

The product guide state...


Nowhere have I asserted with absolute certainty that canards are detrimental to RCS reduction, only that conventional technical wisdom from decades of laboratory and field experience showed that edge diffraction fields are detrimental to RCS reduction if the aircraft design does not take them into consideration. There is no shortage of those literature...

Marietta Scientific, Inc. - RCS Reduction Short Course

Got that? There are different types of traveling waves and that a leading edge does produce a diffraction field.

But here you are trying in vain to dismiss decades worth of technical experience and literature in trying to support the JXX. You are a fanboy of lies and deceit.


No wonder you have so many foolish statement with respect to EM theory, because you are a student of Marietta Scientific, Inc. Hahahaha&#8230;. But if those people want to talk serious academics, I&#8217;ll kick their @ss out of my office door. Those are the parasites of interest groups that suck our taxpayers&#8217; money into their pocket and hoax your credulous boys into nowhere.

I&#8217;m telling you that those physics ignorant Indians thanked you not because you were right in physics, but rather because you are anti-China, as they usually foolishly demonstrate themselves. And you physics are deadly wrong in lots of places, including, but not limited to your previous statements about Bernoulli equation. As a typical low-key Chinese descendant, I normally refuse to be dragged into an academic debase with pseudo-professional and false-expert. Does anyone try to discuss physics with a more ideological fundamentalist than a physicist? Tell us how can one convert Pope into Judaism? :lol:

If your type of fundamentalists are in lead of this country (USA), second &#8220;Christmas go home&#8221; farce will certainly and unfortunately advent in near future, and more innocent people will suffer...

BTW, when can we marlvel you sandwiching an enemy plane of superconductor with your bi-statis radar planes to form a triangle? :rofl:
 
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I would like the readers to take a look at this experiment conducted, not by US, but by India...

http://www.atmsindia.org/tp/2010/se...g wave effect in RADAR images ofTurntable.pdf

Please look carefully at figure 11 as it give the readers a visual example of how surface traveling waves behave when confronted with a 'disruption' in the travel path. This is not a new experiment but a confirmation of many previous one, from field to laboratory. As the highlighted summarized -- That if the radar signal's angle of approach is below 90 deg, or closer to parallel, as in grazing angle, then the diffraction field created by the trailing edge would create a scattering point whose signal strength could be equal to that which came from a flat surface. If this diffraction field came from a canard's trailing edge, which situated in front of a wing, then we could have constructive interference where the diffraction field's signal merged with the radar signal that impact the wing's leading edge to create a stronger return of that leading edge. Or depending on the canard's attitude in flight we may have destructive interference where the diffraction field's signal partially canceling out the same radar signal. We do not know. But the argument presented so far in favor of the JXX's canards as an RCS non-factor does not stand up to technical literature.

Physics wise, I don't see any thing new in the article. It only confirms my earlier statement that EM wave will scatter when inhomogeneity of the medium is encountered.

In glancing incidence situation, as show by the experiment configuration, &#8220;roughness&#8221; of low (spatial) frequency of the surface is more pronounced.

In X-rays band, most condensed matters will have refractive index <1, a more amazing phenomenon (yoneda wings) will appear.
 
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ya the photoshop guys are working hard, we shall see the jet soon :P

This coming from an elite member? Wow... Guess what? FGFA involves India so I guess that's a fail... Un-oh...

It will fail... expect critical design flaws... The Russians have always been angry about India's inability to keep its end of the bargin. And you guys' "over-ability."

Though, the WS-10A is yet to enter service after 8 years of testing. What will be the fate of Kaveri?

lol its was a joke, dont take it so seriously, cheers mate

^^^ A joke would be the LCA Tejas. :cheers:

This thread is hardcore :rofl:
 
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“An airfoil is conducive to surface traveling waves, which do not lose energy as it traverse the wing's surface.” :lol:

Man, you are so reckless! Hahahaha, the mere “conductive” can sustain a traveling wave to stay forever. Gee, you are the person to get fa(ke)sics Nobel Prize soon, as you are in open defiant of energy conservation!

<snipped>

Unless your airplane has wings of superconductor, :rofl: the delta will never be zero as the conductivity is always finite and the wave energy will ALWAYS diminish in the skin of surface.
Superconductor...??? :rofl:

Readers...This is too funny...!!!

An airfoil is conducive to surface traveling waves,...
Here is the definition for 'conducive'...

Conducive - Definition and More from the Free Merriam-Webster Dictionary
: tending to promote or assist

A surface traveling wave cannot exist unless there is a...hmmm...errr...surface...??? So when I said that an airfoil is 'conducive' I do not mean that the airfoil is made up of a 'superconductive' construct but that the airfoil, when it is in interference with an EM wave, the airfoil's surfaces, top and bottom, will PROMOTE the creation and existence of surface traveling waves.

Take a water hose and spray it into empty space. There are no surface traveling waves. Aim that water hose on your car and behold...you will see surface traveling waves all over. Does that mean your car is made up of 'superconductive' materials...?!?!?

Do the readers see how desperate some of these fanboys become? Not only are they willing to violate the laws of physics but in their flawed understanding of the subject under discussion they ended up mocking themselves.
 
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Physics wise, I don't see any thing new in the article. It only confirms my earlier statement that EM wave will scatter when inhomogeneity of the medium is encountered.

In glancing incidence situation, as show by the experiment configuration, “roughness” of low (spatial) frequency of the surface is more pronounced.

In X-rays band, most condensed matters will have refractive index <1, a more amazing phenomenon (yoneda wings) will appear.
Yes...But the point of the experiment, as confirmation of many previous, that a diffraction field is a scattering point, or that it created a scattering point, and that the diffraction field's signal can and usually does return to source direction, contrary to this claim...

...the diffracted signal, by definition of diffraction, cannot travel back toward the source.

...Which is a blatant violation of the laws of physics, which seems to be the common theme among the Chinese members of this forum. I read a fantasy novel a long time ago in my youth about an alternate universe involving China with weapons like the 'chi lance'. You might want to look up the title, which escape me for the moment, and check it out for further creative references.
 
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:rofl:

As I always find: too many people are just too much letting themselves entangled with trivial details but forget the essences of principles. Those people include federal employees, defense expertise, national lab leaders, and even some university professors... Frankly, I’m fed up with those fools. And I don’t understand why you make such a simple thing so complex, provided that you want to fool the credulous.

a) any inhomogeneity of the media will cause EM wave to going in a bent way (roughly speaking).

Canards do introduce the inhomogeneity in general.

If you have any language problems because of your upbringings, from EM point of view, just let you know that dialectic property can be described with permittivity and permeability of the medium, including vacuum. In general they are the function of space (x,y,z) and EM frequencies. If they are constants in terms of space (x,y,z), they are spatially homogenous. If EM wave travels within such a homogenous medium, no scattering, and thus, loosely speaking, no diffraction/reflection will happen.

Why I say it loosely speaking? Because any other phenomena (reflection, diffraction, etc.) are part of scattering. Reflection is specular scattering, diffraction is interference among (in general) forward scattering waves. Diffusion is non-specular scattering. Strictly speaking, when waves move to next position in a medium, it is a result of diffraction (or interference) of all waves from their previous position(s). Thus, we can say all earlier waves are “primary sources” of next waves, and next waves are “secondary sources” to yet the third waves. This is how the “snapshots” are when we strictly and correctly visualized the EM propagation.

If you have a sense of quantum mechanics, those perturbations (inhomogeneity ) to the medium function like potential wells that cause waves to scatter (reflection/scattering/diffraction, what ever you name it.)
The one who is trying to fool the credulous here is YOU. This is what I asked about...

...even with bi-staic radar, a ground station wouldn’t get much signal due to the inhomogeity of the medium.
What the hell is this inhomogeity of the medium when the medium itself is empty space, or air, in a bi-static configuration? A deflected signal off a surface, in a bi-static configuration, travels in empty space. You cannot even keep track of your own argument.

b) In general, direct reflection (specular part) contains the majority of the energy, unless the surface/interface where the wave encountered is very rough. Rough or not is compared with the wavelength. If the size of “humps” or “dents” are comparable with the EM wavelength it is rough. Thus for longer wavelength, a surface usually looks more smooth.

Physically, it is very easy to understand, as specular part of the energy comes as zero-th order approximation from Born Approximation. Any diffuse scattering are in higher order.

This is perhaps why the first order correction for stealth, in general, should be geometrical to deflect the specular part of the energy. Even it will introduce aerodynamic instability, the cost is still comparatively low.

If specular energy is absent due to absorption or deflection or strong diffusion, people may then consider higher order approximations.

Even according you, diffractive energy goes off the front canards and happens(!) to be caught by the wings, yes it serves as a signal, but still 1) in general diffracted energy is weak compared with specular energy, 2) second reflection will make it even weaker. 3) the weak signal may well be intermittent or fortuitous due to the precise match of the paths. Above talk is in absence of specular part.
Fine...Now all you have to do is how the readers a credible source that says diffraction field energy are NOT relevant in RCS calculations. Everything you posted above sounds like a copy/paste job off a textbook. But all it does is explain the energy differences between types of scattering modes, or points. I want to see a credible source that says in RCS calculations, diffraction fields are irrelevant.
 
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