J-20 not yet ready for export: Jane’s Defense Weekly

[gambit]

Since you don't know the materials composition and minute differences regarding size and shape of various structures on the J-20, how can you tell whether the reflected waves are in phase or out of phase with regard to the canards and main wings/fuselage?

Right...So here is where the speculation that the J-20's canards WILL be made out of some super exotic materials that will absorb 100% of impacting signals to render them effectively invisible to radar comes into play. What you asked is nothing more than a rehash of previous Chinese declarations from speculations and baseless speculations at that.

Here is where you are wrong...

...reflected waves are in phase or out of phase with regard to the canards and main wings/fuselage?

On a complex body with many individual structures in many complex arrays, the phase of any reflected wave can be compared against the original wave and against nearby structures. Do you understand?

If the J-20's canards in relation to the fuselage and wings are insufficient in creating destructive interference, how can constructive interference happen either?

Constructive and destructive interference are two sides of the same coin.

If one can happen, so can the other under slightly different conditions.

You continues to be wrong. This is what is called a 'false dichotomy' or false choices. It is not either 'constructive' or 'destructive'.

On a finite body with many complex structures, not every structures will return to the seeking radar at the same time.

If an impacting pulse can have a leading edge and a trailing edge...

...The reflected pulse will also have the same characteristic: a leading edge and a trailing edge.

Anyway...The structure that is closest to the seeking radar will have its reflected signals arrive before the structure that is further.

On a finite body with many complex structures with diverse radar views, especially if the body is under constant motion, there can be constructive interference in one instance, destructive the next, and neither on the next. This is why the RCS value is an average and NEVER fixed. The more the diversity of radar views, the greater the accuracy of that average.

How in the world are you able to know that both reflected signals are in phase with each other by eyeballing some J-20 pictures on the internet?

Now please explain how you're able to determine whether radar waves are in phase or out of phase by eyeballing J-20 pictures online.

I am not the one making declarations here. You guys are the ones saying the J-20's canards are 'irrelevant', so tell us how can you make them just from eyeballing Internet pictures? All I have been saying so far is that based upon known methodologies, the ones that China is just learning how to use, ALL structures are suspect until dismissed by credible measurement data, of which we most likely will never know.

These are the rules of RCS control:

- Quantity of radiators.
- Modes of radiation.
- Array of radiators.

Everything else, including absorbers, falls under those rules. The reduction of all three items is the goal and unless the fighter is a perfect sphere, each item will be compromised in some ways. Any radar engineer, including civilian ones, can vouch for those rules. I have yet to see any of you guys, here or over your other playgrounds, provide the lay readers the foundational principles like these. The J-20's canards are not excluded from these rules, except in Chinese minds.

This is your typical deception. You make BASELESS declarations and demand everyone accepts them. When challenged to support your arguments, you divert by demanding others support theirs.

 

[j20blackdragon]

On a finite body with many complex structures with diverse radar views, especially if the body is under constant motion, there can be constructive interference in one instance, destructive the next, and neither on the next.

Your argument has completely changed.

Now it's constructive interference in one instance, destructive the next, and neither on the next (which I agree with by the way).

What happened to your earlier argument about the canards being in front of the main wings and running the greater risk of constructive interference in post #50?

J-20 not yet ready for export: Jane’s Defense Weekly

Likewise with the canards. A design with canards may have the same quantity of flight control structures as the conventional tailplane design, but because the canards are in front of the main wings, we run the greater risk of constructive interference that may raise the body over a certain threshold.

This is why aviation experts around the world casts doubts upon the J-20 being a 'stealth' design despite not one of them knowing measurement data. Unlike you guys' baseless declaration of 'insignificant', their doubts are sound and based upon real physics and experience.

I cannot dumb this down further, fraud.

Remember, you're the one that brought up constructive interference in the first place.

 

[gambit]

Your argument has completely changed.

Now it's constructive interference in one instance, destructive the next, and neither on the next (which I agree with by the way).

What happened to your earlier argument about the canards being in front of the main wings and running the greater risk of constructive interference in post #50?

J-20 not yet ready for export: Jane’s Defense Weekly



Remember, you're the one that brought up constructive interference in the first place.

Which part of 'risk' do you NOT understand? The word 'risk' implies uncertainty but with a tendency towards. Why is that so difficult to grasp? Never mind that. It was rhetorical anyway.

 

[Genesis]

But those who support the J-20 are exempt from this? Guess so...


There are certain laws of physics, or programming, that neither Chinese engineers nor you nor Ellison can violate. For programming, memory allocation is one example. For RCS control, I explained some of those basic inviolable rules here....

What are you 5? Or first time on a forum? After 10,000+ posts you think you know how a forum works. So because some other people do this now I must?

That's not the reasoning of a professional but one of a preschooler.


As to laws of physics, how do you know the Chinese engineers have violated, it's like when we are explaining things to some of our clients, they are asking for things we are either clearly doing or have a way better way of doing it, but they just can't understand it and continue pretending they know what they are talking about.

If the Chinese engineers told you exactly why they did it the way they did, it will appear so simple, but without knowing the details, you make assumptions that our engineers are somehow ignoring BASIC physics?

Do you know the story of brunelleschi and his standing of an egg? Seemingly impossible but once explained it makes sense.

Lastly, some claims are crazy and are in no way representative of the project, but somehow you make it sound as if the head engineer himself had publish the claim. Most professionals would ignore a claim so ridicules that discussing it would be a waste of time.

Don't do this I know you are but what am I. This isn't day care playground, it's an elementary playground.

 

[longlong]

What are you 5? Or first time on a forum? After 10,000+ posts you think you know how a forum works. So because some other people do this now I must?

That's not the reasoning of a professional but one of a preschooler.


As to laws of physics, how do you know the Chinese engineers have violated, it's like when we are explaining things to some of our clients, they are asking for things we are either clearly doing or have a way better way of doing it, but they just can't understand it and continue pretending they know what they are talking about.

If the Chinese engineers told you exactly why they did it the way they did, it will appear so simple, but without knowing the details, you make assumptions that our engineers are somehow ignoring BASIC physics?

Do you know the story of brunelleschi and his standing of an egg? Seemingly impossible but once explained it makes sense.

Lastly, some claims are crazy and are in no way representative of the project, but somehow you make it sound as if the head engineer himself had publish the claim. Most professionals would ignore a claim so ridicules that discussing it would be a waste of time.

Don't do this I know you are but what am I. This isn't day care playground, it's an elementary playground.

No need talk too much to him. He repeated copy and paste his 1980's infant stealthy physics again and again. He is too old to remember what he'd lied and believed they are true after thousands times of cheating.

He is blind at F-22's 1)two giant V-tails, 2) two giant main wings 3) big gaps btw inlet and body
He is good sighting at J-20 1) two small canards....

(J-20's canards are really different from the rest of the canarded aircraft, its shape, angle, position and size)

 

[gambit]

No need talk too much to him. He repeated copy and paste his 1980's infant stealthy physics again and again. He is too old to remember what he'd lied and believed they are true after thousands times of cheating.

He is blind at F-22's 1)two giant V-tails, 2) two giant main wings 3) big gaps btw inlet and body
He is good sighting at J-20 1) two small canards....

(J-20's canards are really different from the rest of the canarded aircraft, its shape, angle, position and size)

And two giant V-tails, two main delta wings, two ventral fins...

 

[longlong]

J-20 does have smaller V-tails just half of F-22's.

V-fin is going to be removed, who knows. 

J-20 does have smaller V-tails just half of F-22's.

V-fin is going to be removed, who knows.

 

[rott]

@j20blackdragon :

Would you mind telling us who is in your avatar?

She is so hot!

Yea, I wanted to suggest her/him being taken off as it's attracting a lot of my attention during reading posts. LOL 

Then confirm that you are narcisistic



Why must you be always OOT when you are already trapped?

See again what chinese members are asking you and you havent addressed yet.
The significance of static canard's rcs contribution of J-20.



In fact you are not addressing what people asking here.

We are here talking about RCS of the static canard, in comparison with other object like bump, gap, etc.

Remember your indian fellow claiming that J-20 is not a stealth fighter like F-22, F-35, and PAKFA, just because J-20 has canard. Chinese member explain that static canard contribution to RCS is relatively small compared to other object like gap, bump.

This is what we are talking and discussing.



No, instead we are the ones who should ask you upon what technical foundation can you declare that static canard contribute RCS significantly?

It is your indian fellow that make claim that J-20 is not stealth a/c because of its canard, and you refuse chinese member's explanation that canard contribution should be relatively low.

And as I said, they can assume that J-20's static canard could be designed to behave like small wing in term of RCS.



That is only assumption. Remember we are talking static canard.

Bring any citation that can support your claim that static canard will certainly cause constructive interference that will certainly raise the body over a certain threshold. Otherwise, it is confirmed that you are fraud.

And other member has explained to you : what if china design canard so well designed that they cause destructive interference, which would lower RCS.



Dont call other fraud.
It is you who claim to have solid experience, solid education and solid expertise in Aviation.

If you cannot address what people asking regarding what you have claimed, then you are the one who is fraud.




You have asked, and I have answered you in previous thread.
Why always OOT with this?

I have exposed your fraud from the very beginning of our discussion, when you claim that Nozzle and airduct of Pakfa should called "Nacelle", then I busted you with citation what nacelle is, and nacelle is not the same as nozzle or airduct. Should i refresh your memory?



If you now admit that you need measured data, then why you drag rubbish like the above?

Just admit it that static canard of J-20 could also contribute relatively low RCS compared to other object in other 5 gen a/c (gap, bump, round nozzle)

 

[Zabaniyah]

My brain is starting to ache after going through the thread!

 

[wangyifen]

I think it takes a long time when to service. Let alone export. But I believe that time will come.