Chengdu J-20 5th Generation Aircraft News & Discussions

[ohmrlobalobayeh]

But do You have in return any technical valid argument to counter his claim?? Why should it be with all the issues he - and I added a few more - reach the same level of stealth?? What about the nozzles, what about the non-alignment, what about the clearly visible chaff&flare-boxes ?? I know there are maybe methods to make them stealthy but as long as they are visible the way now, it need to be discussed.
Only to say the Chinese must know their business or he is stupid - honestly to say so - is not an argument. Otherwise the Russian T50 must be already a 6.5th generation fighter if one follows all that hype in some Russian forums...

Again: I can understand all Your feelings and the J-20 is not only a giant leap in Chinese aeronautic achievements; it's more ... but is not a magical bird. It has to obey the laws of Physics in the same way as all other aircrafts and if there are certain "points of concern" ... then let's argue.

Why do I have to counter his claim? if u backtrack my replies to his claims, i merely requested:

do show us how you drew up that conclusive statement when ironically, you have already acknowledged yourself that:

Nevertheless, I have consistently been fair and advised everyone from making definitive statements simply because the measurement data for all these aircrafts are not public information.

Source: https://defence.pk/threads/chengdu-...tes-discussions.111471/page-422#ixzz4Nyzxb8xr

Source: https://defence.pk/threads/chengdu-...tes-discussions.111471/page-422#ixzz4NyzpeVfc

in order to let me understand why he he claimed what he claimed.

Yet all i can see in his replies are 'because this design doesnt fit with my opinion of how XXX should be designed' .

I dont need a PHD in aircraft engineering to see the gap in his arguement. I think even my grandma could tell that he has no sustantial proof to his claims.

 

[Deino]

I agreed. I just want to hammer in the point that even if the canards are not stealthy to begin with, engineers CAN make them stealthy. China has all the resources it need to make this happen. And the laws of Physics don't prevent this from happening. I doubt that this problem is even difficult to begin with. It's just some fanboy got stuck with this idea that canards are stealthy and hold on to it.

YES they can, but by simply looking at the images, some points of concern mentioned above are simply not solved in a stealthy way !! So PLAESE argue with an argument how they could solve the issues mentioned. Only by telling "they are solved" and hammering him as ignorant or arrogant they are not solved in any way.

Explain, why do You think "this problem is even difficult to begin with" ?? Believe is no technical valid point.

 

[Asoka]

YES they can, but by simply looking at the images, some points of concern mentioned above are simply not solved in a stealthy way !! So PLAESE argue with an argument how they could solve the issues mentioned. Only by telling "they are solved" and hammering him as ignorant or arrogant they are not solved in any way.

Explain, why do You think "this problem is even difficult to begin with" ?? Believe is no technical valid point.

The Chinese engineers don't need to "simply looking at the images" , they have all the advanced modeling software and RCS/Radar chamber to test their designs. I have confidence that they know how to solve this problem and it's already solved, since it's not insurmountable to begin with.

"Explain, why do You think "this problem is even difficult to begin with" ?

It is no more difficult to solve than the RCS problem of other parts of the plane, I am contending. There are no suggestions from anyone that this is a difficult problem. Not even from Gambit. He was just keep arguing that having canards is unfavorable to stealthy. Not even he has suggested that it is not possible to reduced the resulting RCS!

 

[Deino]

O.k. ... then let's at least agree we do not agree in all issues ! o.k ?

 

[gambit]

I don't doubt that LM has the resource to built a full mockup of J-20 to see how stealthy of the design. But you certainly don't have resources and you certainly have not done any testing on J-20 or even go near it. So stop insulting the Chinese by suggesting we can't solve the problem of making the canard stealthy. You have no proof that J-20 is not stealthy as it is now. You are only making a fool of yourself or making yourself feel good, foolishly.

Here is something for you to chew on...

What we have are four radomes: F-15, F-22, F-35, and J-20.

Why do the radomes of the newer jets, meaning not the F-15, shaped that way ? Why do those three radomes have ridges ?

I do not have measurement data for all four jets. But based on my personal experience in aviation, in and out of the military, I am %99.999 confident of my guess as to why.

I will give you a hint: It has to do with radar signals behavior on a conic.

The laws of physics are non-negotiable, not even Chinese scientists can try. What I gave you my trainees from more than ten yrs ago can guess in less than one minute with the same high confidence.

See if any of you can figure out why.

 

[grey boy 2]

 

[Asoka]

Here is something for you to chew on...

What we have are four radomes: F-15, F-22, F-35, and J-20.

Why do the radomes of the newer jets, meaning not the F-15, shaped that way ? Why do those three radomes have ridges ?

I do not have measurement data for all four jets. But based on my personal experience in aviation, in and out of the military, I am %99.999 confident of my guess as to why.

I will give you a hint: It has to do with radar signals behavior on a conic.

The laws of physics are non-negotiable, not even Chinese scientists can try. What I gave you my trainees from more than ten yrs ago can guess in less than one minute with the same high confidence.

See if any of you can figure out why.

The horizontal ridge along the middle of the nose is used to create uplifting surface to create more lift.

Why do the newer radomes have sawtooth edges? The radome itself is transparent to radar signal, but the part attached to the radome itself is not. So edge could bounce back signals. The sawtooth edges are made at an angle to reduce the signal bouncing back to the enemy.

 

[grey boy 2]

 

[gambit]

YES they can, but by simply looking at the images,...

You are correct. See post 6350 with the different radomes.

I am willing to guess that when the J-20's engineers were looking for solutions on how to design the jet, they took one look at the F-22's radome and said: 'A-ha...!!!' Or the Chinese equivalent expression.

They would not need to know the F-22's measurement data to know that such a design would solve one of their problems.

But they would also know that such a radome design would increase the problem of 'radome aberration'...

http://arc.aiaa.org/doi/abs/10.2514/3.21438

So in solving one problem, they created or increased the complexity of another.

These guys just do not know how much can be inferred, and accurately, just from looking at images.

The horizontal ridge along the middle of the nose is used to create uplifting surface to create more lift.

Wrong. This is not about aerodynamics. I did said 'radar signals behavior on a conic', did I not ?

I will give you a second hint: Ten lambda behavior.

That is two more hints than I would give my trainees.

 

[grey boy 2]

 

[gambit]

I don't doubt that LM has the resource to built a full mockup of J-20 to see how stealthy of the design. But you certainly don't have resources and you certainly have not done any testing on J-20 or even go near it. So stop insulting the Chinese by suggesting we can't solve the problem of making the canard stealthy. You have no proof that J-20 is not stealthy as it is now. You are only making a fool of yourself or making yourself feel good, foolishly.

"It is reasonable to place the J-20's canards under suspicion. That is professional."

Sure, I agreed. One can be suspicious about the canard. But it's also easy to see that with all the resources the Chinese has, and engineering skills demonstrated, it's not a difficult problem to fix. Get that into you head. It's not a big problem to fix, if someone can make B2 bomber stealthy. What's a little canard compared to the huge B2 bomber? Let's not fixated on it and keep making a fool out of yourself, Gambit.

So basically, you are saying you have only faith that the J-20's engineers did 'something' to minimize or even render the canards statistically insignificant.

I have the laws of physics on my side to put the canards under professional suspicions. Not just me but so do many outside of this forum. You have only faith that the problem is fixed.

 

[cnleio]

is second pics is real sir?

2nd is a CG.

 

[Deino]

Wrong thread ?????

 

[Asoka]

You are correct. See post 6350 with the different radomes.

I am willing to guess that when the J-20's engineers were looking for solutions on how to design the jet, they took one look at the F-22's radome and said: 'A-ha...!!!' Or the Chinese equivalent expression.



They would not need to know the F-22's measurement data to know that such a design would solve one of their problems.

But they would also know that such a radome design would increase the problem of 'radome aberration'...
So in solving one problem, they created or increased the complexity of another.

These guys just do not know how much can be inferred, and accurately, just from looking at images.


Wrong. This is not about aerodynamics. I did said 'radar signals behavior on a conic', did I not ?

I will give you a second hint: Ten lambda behavior.

That is two more hints than I would give my trainees.

"Wrong. This is not about aerodynamics. I did said 'radar signals behavior on a conic', did I not ?


Professional Chinese aviation engineers have said those horizontal edges along the nose is used to create vortexes to maximize lift and maneuverability. I will take their words over a fanboy's.

So basically, you are saying you have only faith that the J-20's engineers did 'something' to minimize or even render the canards statistically insignificant.

I have the laws of physics on my side to put the canards under professional suspicions. Not just me but so do many outside of this forum. You have only faith that the problem is fixed.

You don't have the laws of physics on your side. Your understanding may be flawed. You are not a professional aviation engineer. You have no working experiences or even superficial knowledges in this field. You don't have extensive measurements and test results to back up and verify your claims. Chinese engineers have vast amount of resources and experiences to minimizes the effect of canard on RCS. This is my point and I stick with it.

Not even you or anyone has claimed that the canard's RCS can not be minimized or reduced drastically. So stop making a fool of your self with your little bit of 'knowledge' or misunderstanding.

 

[Deino]

Professional Chinese aviation engineers have said those horizontal edges along the nose is used to create vortexes to maximize lift and maneuverability. I will take their words over a fanboy's.

You don't have the laws of physics on your side.
Your understanding may be flawed.
You are not a professional aviation engineer.
You have no working experiences or even superficial knowledges in this field.
You don't have extensive measurements and test results to back up and verify your claims.

Chinese engineers have vast amount of resources and experiences to minimizes the effect of canard on RCS. This is my point and I stick with it.

....

Asok ... again especially since You are new here. PLESAE argue instead of pure accusations.
Do You know gambit's background? Are You sure that he is none of the things You claim he's not ... ??

And in return do You have a degree in aeronautical engineering ??

By the way I still miss YOUR explanation, why the J-20's nozzle should be as stealthy as the F-35 ones, why are fully open chaff-and-flare dispensers are as stealthy as enclosed systems

Again; give an argument and a contra-argument and then it's fine so everyone can make his own mind or otherwise You are in exactly the same position: So stop making a fool of your self with your little bit of 'knowledge' or misunderstanding !

.. and aren't most of us fan-boys in the one or the other way?

Deino