Chengdu J-20 5th Generation Aircraft News & Discussions

[gambit]

I see.
so is J-20 multi-role or just air superiority?
I wonder how the canards effect stealth.

You can go here...

Fundamentals of Stealth Design & Concepts of RCS Reduction

...And read about the foundation of designing a radar low observable body.

But I will sum it up for you:

- Nothing is invisible in radar detection. Radar sees all.

- Everything on a complex body is a 'radiator' or 'emitter' of radiation, whether that radiation of reflected or powered transmission.

- Therefore, the rules for designing a radar low observable body are:
1) Control the quantity of radiators.
2) Control the array of radiators.
3) Control the modes of radiation.

The J-20's canards made the aircraft immediately suspect under those rules. Nevertheless, to be fair, in the absence of hard measurement data, we should refrain from making definitive judgements. China will never release those measurement data,, just as the US will never release the F-22's version.

 

[Genesis]

You can go here...

Fundamentals of Stealth Design & Concepts of RCS Reduction

...And read about the foundation of designing a radar low observable body.

But I will sum it up for you:

- Nothing is invisible in radar detection. Radar sees all.

- Everything on a complex body is a 'radiator' or 'emitter' of radiation, whether that radiation of reflected or powered transmission.

- Therefore, the rules for designing a radar low observable body are:
1) Control the quantity of radiators.
2) Control the array of radiators.
3) Control the modes of radiation.

The J-20's canards made the aircraft immediately suspect under those rules. Nevertheless, to be fair, in the absence of hard measurement data, we should refrain from making definitive judgements. China will never release those measurement data,, just as the US will never release the F-22's version.

the question is why put it on there if it's such an obvious flaw? I mean we might not be technically advanced, but we are at least not retarded are we.

What does a canard do exactly, would a pair justify their existence by its usefulness.

 

[longlong]

You can go here...

Fundamentals of Stealth Design & Concepts of RCS Reduction

...And read about the foundation of designing a radar low observable body.

But I will sum it up for you:

- Nothing is invisible in radar detection. Radar sees all.

- Everything on a complex body is a 'radiator' or 'emitter' of radiation, whether that radiation of reflected or powered transmission.

- Therefore, the rules for designing a radar low observable body are:
1) Control the quantity of radiators.
2) Control the array of radiators.
3) Control the modes of radiation.

The J-20's canards made the aircraft immediately suspect under those rules. Nevertheless, to be fair, in the absence of hard measurement data, we should refrain from making definitive judgements. China will never release those measurement data,, just as the US will never release the F-22's version.

You rules can only be filtered by J-20 two canards and bypassed by two giant wings of F-22.

 

[Basel]

@gambit but Boeing a US company concept of 6th gen have canards, if they are not good for stealth then why a company which have tones of experience in building air crafts put canards in a 6th gen concept where stealth is core ingredient?

 

[Superboy]

I see.
so is J-20 multi-role or just air superiority?
I wonder how the canards effect stealth.

It is air superiority. Canards do not affect stealth because instead of being at the back they are not at the front.

@gambit but Boeing a US company concept of 6th gen have canards, if they are not good for stealth then why a company which have tones of experience in building air crafts put canards in a 6th gen concept where stealth is core ingredient?

View attachment 43301

Dude, does Boeing even have DSI technology? I don't think so.

 

[Basel]

Dude, does Boeing even have DSI technology? I don't think so.

Your post just show how much you understand about aviation (although I m not an expert too), dude Boeing is giant in aviation and DSI is not a big deal to have in air craft if required for that kind of company, although they may prefer "S" type inlets which will allow much smoother & faster flights at most altitudes.

 

[Beast]

Song wencong did mention about RCS contribution of canard in his report. But he also mention with careful alignment and ram coating. The RCS contribution will be significantly reduced.

The canard boast superior agility for J-20 layout which advance far outweigh the disadvantage.

 

[hk299792458]

Song wencong did mention about RCS contribution of canard in his report. But he also mention with careful alignment and ram coating. The RCS contribution will be significantly reduced.

The canard boast superior agility for J-20 layout which advance far outweigh the disadvantage.

Henri K.

 

[Superboy]

Your post just show how much you understand about aviation (although I m not an expert too), dude Boeing is giant in aviation and DSI is not a big deal to have in air craft if required for that kind of company, although they may prefer "S" type inlets which will allow much smoother & faster flights at most altitudes.

Why display a graphics plane that has DSI when Boeing doesn't have DSI technology?

 

[That Guy]

Why display a graphics plane that has DSI when Boeing doesn't have DSI technology?

Because US corporations regularly cooperate with each other. Besides, Boeing could very well research such a tech on their own, but they have no need right now, as none of their clients have asked them for such a requirement.

 

[gambit]

@gambit but Boeing a US company concept of 6th gen have canards, if they are not good for stealth then why a company which have tones of experience in building air crafts put canards in a 6th gen concept where stealth is core ingredient?

View attachment 43301

If we take that drawing as planned, then what Boeing did still followed the basic rules of control of radiators.

Look at the drawing again. You will see the concept aircrafts have no vertical stabs, which equals to the rule: control of QUANTITY of radiators.

The location of the canards falls under the rule: control of ARRAY of radiators.

For all we know, the Boeing version of the canards may be superior to the J-20. Or equal to. Or inferior to. For now, we just do not know.

It is air superiority. Canards do not affect stealth because instead of being at the back they are not at the front.

Dude. Shut up. You do not know what the hell you are talking about.

Dude, does Boeing even have DSI technology? I don't think so.

Dude. Shut up. DSI is a well known technology.

 

[j20blackdragon]

If I were gambit, I would worry less about the J-20's planform aligned canards and worry more about the large gaps around the F-22's inlets.

I would also worry about the F-35's multiple forward facing cavities, circled in red here.

Any comments on gaps and cavities gambit?

 

[gambit]

If I were gambit, I would worry less about the J-20's planform aligned canards...

Unfortunately for you, the J-20's canards are NOT aligned. In the frontal view, they are angled upward. That is not planform aligned.

...and worry more about the large gaps around the F-22's inlets.

I would also worry about the F-35's multiple forward facing cavities, circled in red here.

Any comments on gaps and cavities gambit?

And you think the J-20 have no such gaps ?

 

[longlong]

Unfortunately for you, the J-20's canards are NOT aligned. In the frontal view, they are angled upward. That is not planform aligned.


And you think the J-20 have no such gaps ?

Yep, J-20 does have.

If I were gambit, I would worry less about the J-20's planform aligned canards and worry more about the large gaps around the F-22's inlets.

I would also worry about the F-35's multiple forward facing cavities, circled in red here.

Any comments on gaps and cavities gambit?

Don't compare the J-20 with F-22 (a failed project) and F-35 (worse than fail).

Look at it, what a joke. Asymmetric face and body.

 

[gambit]

Yep, J-20 does have.

And how do those gaps affect the J-20's radar cross section. We want reasonably technical observation, if not hard data.

Don't compare the J-20 with F-22 (a failed project) and F-35 (worse than fail).

How can you say the F-22 is a 'failed project' ? Because of the quantity produced ? And how can you say the F-35 is also a 'failed project' ? Because of its development problems ? What make you think the J-20 does not have its own development problems ? Going by your simple minded thinking, I can say that by virtue of the J-20 came from the MIG 1.44, which was never mass produced, that mean the J-20 is already a failed project.