Chengdu J-20 5th Generation Aircraft News & Discussions

[LKJ86]

Via @耿直的鲁斯兰 from Weibo

 

[gambit]

Interesting, the J-20 was referred to as China's first "supersonic stealth fighter." So the J-20 can supercruise after all it seems.

Wrong. Supersonic and supercruise are not the same thing. They are not even synonymous.

Supersonic is faster than Mach. Supercruise is faster than Mach without using afterburner.

Yeah but stealth fighters jet isn't invincible in any war with any near peer enemy,...

The problem with this idiotic criticism is that no one -- not even China -- want to fight a near peer adversary.

How do you not fight a near peer adversary? Two ways:

- By actually avoiding a near peer adversary
- By being so far ahead that there is no near peer adversary

Using Europe as an example. There are many countries in Europe and most of them are near peer to each other. Of those who are near peer status to each other, of course there are gradations among them as to who have numerical quantity over who else, but overall, in terms of technology and quantity, they are near peers. The same can be said to Africa and the ME.

f35 detected by a unknown company with unsophisticated makeshift of passive radar, you can only imagine Russia and China with their sophisticated radar system waiting on F35 flight into their airspace during the war.

And imagination is all they have.

The F-22, F-35, and B-2 do not need to be 'invincible', just difficult enough. You do not know what you are talking about.

 

[phancong]

Wrong. Supersonic and supercruise are not the same thing. They are not even synonymous.

Supersonic is faster than Mach. Supercruise is faster than Mach without using afterburner.


The problem with this idiotic criticism is that no one -- not even China -- want to fight a near peer adversary.

How do you not fight a near peer adversary? Two ways:

- By actually avoiding a near peer adversary
- By being so far ahead that there is no near peer adversary

Using Europe as an example. There are many countries in Europe and most of them are near peer to each other. Of those who are near peer status to each other, of course there are gradations among them as to who have numerical quantity over who else, but overall, in terms of technology and quantity, they are near peers. The same can be said to Africa and the ME.


And imagination is all they have.

The F-22, F-35, and B-2 do not need to be 'invincible', just difficult enough. You do not know what you are talking about.

Whatever I'm not interest in your expertise.

 

[gambit]

Whatever I'm not interest in your expertise.

Of course you are. Do not try to deny it. Nowhere else in the Chinese forums will you find information like I presented here. Since '09, no one have taken what I posted, independently checked, returned to the forum, and proved I misled the readers. In your case, what I posted went whooooooshed over your head so you have to act like you are not interested. But we know you are...

 

[serenity]

Yes Phancong. A American stealth fighter is more effective against for example Finland or Zimbabwe than it will be against Russia or China due to the near peer status we call it because on military matters Russia and China are more likely to face F-22 for example and have spend much more resources to diminish stealth fighter's ability compared to what we would call non-near peer player who doesn't care and will not have stealth fighter used against them.

But detecting F-35 recently they didn't mention how they detect and quality of tracking. Maybe they also can't target F-35 just detect presence. Anyway too little information provided to say anything important about stealth. But of course many resources are used by some very clever people to diminish and counter improvements to stealth technology. Only in a war can we know how effective everything is.

 

[yantong1980]

Yes Phancong. A American stealth fighter is more effective against for example Finland or Zimbabwe than it will be against Russia or China due to the near peer status we call it because on military matters Russia and China are more likely to face F-22 for example and have spend much more resources to diminish stealth fighter's ability compared to what we would call non-near peer player who doesn't care and will not have stealth fighter used against them.

But detecting F-35 recently they didn't mention how they detect and quality of tracking. Maybe they also can't target F-35 just detect presence. Anyway too little information provided to say anything important about stealth. But of course many resources are used by some very clever people to diminish and counter improvements to stealth technology. Only in a war can we know how effective everything is.

Agree, but sometime some 'hint' may come up in peace time also.

 

[LKJ86]

Via @航空物语 from Weibo

 

[LKJ86]

Via @央广军事 from Weixin

 

[vi-va]

It is good enough. The problem with you is that you allowed your nationalistic passion takes over your critical thinking skills. A behavior common to the Chinese members here. And I say that kindly.

Let us take a look at this illustration again since you repeatedly failed to understand it...

Somewhere in those clusters of voltage spikes, there are spikes from doors and windows. But can you see them? Can you distinguish which spike came from which structure? No, you cannot and neither can any radar system, including Chinese ones.

You can call the classic diverter plates as inferior to the DSI 'bump' all you want but in the larger scheme of things, its supposedly 'inferior' design is irrelevant.

There is something called 'interference' and there are two types of interference:

- Constructive
- Destructive

In designing a low radar observable body, we want DESTRUCTIVE interference. It means to cancel out.

https://www.phys.uconn.edu/~gibson/Notes/Section5_2/Sec5_2.htm

Are the signals from the F-22's classic diverter plates canceled out by signals from other structures nearby? Only Lockheed knows.

The diverter plate is not a good design? Only in your delusions. The bottom line is that the F-22's intakes did not matter one whit.

On the other hand, unlike the F-22's intake diverter plates, the J-20's canards are visible most of the time in most flight aspect angles. Their positions on the fuselage do not make possible destructive interference. The canards are CONSTANTLY exposed. So when experts commented about the canards as being negative for 'stealth', they do not comment because they are anti-China but do so from the laws of physics.

The problem for you guys is that I posted these explanations REPEATEDLY since '09. New Chinese members comes and predictably, each of them thinks he posted something new and predictably, each got debunked by me. Just like you got schooled.

When Chinese said you schooled me, it's modesty. I think it's culture difference.

Every intake on F-22 or J-20 will use absorbing materials and destructive interference and some other technologies which I don't know to reduce reflection. What they can do depends on the technologies they mastered which none of us knew exactly.

The canards will not move much in most cases, the overall impact is uncertain since we don't know the composition neither.

There are a lot of new technologies after F-22 was born, some of them may be adopted in F-35, or J-20 which none of us knew exactly.

Without accurate intelligence, it's very hard to make a judgement just base on with or without canards. The overall RCS depends on overall body design, as well as radar, composition, absorbing materials and many other things. Canard is just one of the many.

Regarding Russia, China, and U.S. All three countries use AEW&C heavily. AEW&C see stealthy jet from different angle. As I pointed it previously, stealthy jet can't fly too high or too fast, otherwise it will be detected from further distance by infrared detectors array. AEW&C can fly much higher. You can imagine, the angle is different, J-20, F-22 back are exposed to AEW&C.

Also, Russa Su-35 use L band as well (Su-57 not sure). None of the stealthy jets were designed for L band, it will be detected anyway.

Chinese AEW&C use dual band if I remember right. It's not hard to guess why they use dual band. F-22 is not as stealthy as before when facing Chinese dual band AEW&C.

 

[Su33KUB]

When Chinese said you schooled me, it's modesty. I think it's culture difference.

Every intake on F-22 or J-20 will use absorbing materials and destructive interference and some other technologies which I don't know to reduce reflection. What they can do depends on the technologies they mastered which none of us knew exactly.

The canards will not move much in most cases, the overall impact is uncertain since we don't know the composition neither.

There are a lot of new technologies after F-22 was born, some of them may be adopted in F-35, or J-20 which none of us knew exactly.

Without accurate intelligence, it's very hard to make a judgement just base on with or without canards. The overall RCS depends on overall body design, as well as radar, composition, absorbing materials and many other things. Canard is just one of the many.

Regarding Russia, China, and U.S. All three countries use AEW&C heavily. AEW&C see stealthy jet from different angle. As I pointed it previously, stealthy jet can't fly too high or too fast, otherwise it will be detected from further distance by infrared detectors array. AEW&C can fly much higher. You can imagine, the angle is different, J-20, F-22 back are exposed to AEW&C.

Also, Russa Su-35 use L band as well (Su-57 not sure). None of the stealthy jets were designed for L band, it will be detected anyway.

Chinese AEW&C use dual band if I remember right. It's not hard to guess why they use dual band. F-22 is not as stealthy as before when facing Chinese dual band AEW&C.

stealth is not invisibility, it is an attempt to make harder for the opposition to detect them, all radars will detect J-20 or F-22, the problem is always the range, light as well as radar are electromagnetic waves, they have diffraction, in few words light as well as radar bend their paths, light when diffracted by a prism has all the colors with different angle of diffraction, destructive interference does not mean radar will be silenced, it means in some parts you have a stronger signal in others no signal.

Use this analogy if your eyes can see J-20 or F-22, then a radar will do it too.

Now our eyes have limits, if you have not the sun, you will be unable to see anything at night unless you have a lamp, how far you can see in the night will depend upon the power of your lamp or the light of the moon and stars.


Radar is a lamp, a strong lamp will let you see farther, but as things are father from your eyes you see less details, radar has the same troubles, but aircraft are not build upon one material, but many so no aircraft can be invisible is like X-rays, bones will appear very well while some organs will be not visible, no aircraft is invisible all are visible, you have only to create more effective radars and a better radar network, that implies money, poor nations with a few radars have wide gaps of detection so stealth still is effective, most superpowers spent huge amounts of money in radar networks, J-20 pretty much needs air bases, due to the need to have maintenance, this implies easy to destroy on the ground, same are F-22 or F-35s, only F-35B is kind of an exception, so in all out war, stealth will be proven ineffective, then is when fighters like J-10, Su-35 or Gripen will be proven more effective, stealth is a bluff, a needed bluff, but remember in 1999, F-117s were escorted by F-15s and one was shot down and according to some sources 2 more damaged.

then you can see why stealth and speed is a must, faster aircraft have a narrower time window to be shot down, supercruise then is much more important, than stealth

 

[LKJ86]

Via CCTV 13 and @沉默的山羊 from Weibo

 

[Deino]

Well, a nice image of 78272 from the 176th Briagde

 

[gambit]

Every intake on F-22 or J-20 will use absorbing materials and destructive interference and some other technologies which I don't know to reduce reflection. What they can do depends on the technologies they mastered which none of us knew exactly.

You are doing exactly what amateurs do, which is to focus on one thing as if that thing is all that mattered. You saw the DSI intake design as somehow 'superior' to the classic diverter plate so...A-ha...!!! The F-22 will be inferior to the J-20. That is not how it works.

In this image...

The F-22's diverter plates are not visible but the J-20's intakes are clearly visible. Yes, we can see the J-20's intakes are treated with absorbers -- the darker grey areas -- but absorbers do not zero any diffraction signals, only reduce their intensity. Whatever that radiate off into free space WILL interact with the rest of the jet.

The F-22's intake diverter plates and the J-20's DSI 'bumps' do not matter. The intakes themselves -- are.

I do not understand why this is so difficult to grasp even when photographic evident are aplenty.

The canards will not move much in most cases, the overall impact is uncertain since we don't know the composition neither.

The canards do not have to move.

The word I have been using for yrs on PDF is 'contributor'. You have to understand that in the context of designing a low radar observable body, EVERYTHING contributes to final RCS. If a structure, no matter how small like a rivet head or how large like a fin, is 'seen' by the radar, it is a contributor to that temporary RCS value as calculated by the radar computer. As the jet maneuvers, its RCS fluctuates because various structures' visibility changes. But as long as a structure have any chance of being exposed in the radar stream, it contributes to that RCS calculation.

If you think I used the word 'contributor' with no technical validity, think again...

https://www.science.gov/topicpages/r/radar+cross-section+rcs
Typical vehicle components are also discussed, together with their contribution to total vehicle RCS and their individual signature sensitivities.

Do you see the highlighted? Vehicle components -- like the canards -- adds up to total vehicle RCS.

When the J-20 maneuvers, the canards will move, no matter how slightly...

- Control of QUANTITY of radiators
- Control of ARRAY of radiators
- Control of MODES of radiation

...The canards will fall under rule two: Control of ARRAY of radiators.

If a canard moves just a few centimeters to maneuver the jet, any radar signal that exit that canard will impact nearby structure in different angles, changing 'total vehicle RCS', even if just for one second. We do not know it, but that one second maybe just long enough to reveal the J-20.

So when experts opined that the J-20's canards are negative to 'stealth', you may argue they are being hyperbolic, but they are not technically in error.

Regarding Russia, China, and U.S. All three countries use AEW&C heavily. AEW&C see stealthy jet from different angle. As I pointed it previously, stealthy jet can't fly too high or too fast, otherwise it will be detected from further distance by infrared detectors array. AEW&C can fly much higher. You can imagine, the angle is different, J-20, F-22 back are exposed to AEW&C.

IR is not the solution to 'stealth' any more than the supposedly 'passive' radar can. As for AWACS, no one have more experience in using AWACS in combat than US and that includes how to evade AWACS.

Also, Russa Su-35 use L band as well (Su-57 not sure). None of the stealthy jets were designed for L band, it will be detected anyway.

Chinese AEW&C use dual band if I remember right. It's not hard to guess why they use dual band. F-22 is not as stealthy as before when facing Chinese dual band AEW&C.

Long wavelengths have been debated here before and I debunked their claimed efficacy many times over. When you broadcast in whatever long wavelengths, I will see you and take evasive measures before you can see me, to put it simply.

 

[LKJ86]

Via CCTV 13 and @沉默的山羊 from Weibo

 

[vi-va]

You are doing exactly what amateurs do, which is to focus on one thing as if that thing is all that mattered. You saw the DSI intake design as somehow 'superior' to the classic diverter plate so...A-ha...!!! The F-22 will be inferior to the J-20. That is not how it works.

In this image...

The F-22's diverter plates are not visible but the J-20's intakes are clearly visible. Yes, we can see the J-20's intakes are treated with absorbers -- the darker grey areas -- but absorbers do not zero any diffraction signals, only reduce their intensity. Whatever that radiate off into free space WILL interact with the rest of the jet.

The F-22's intake diverter plates and the J-20's DSI 'bumps' do not matter. The intakes themselves -- are.

I do not understand why this is so difficult to grasp even when photographic evident are aplenty.


The canards do not have to move.

The word I have been using for yrs on PDF is 'contributor'. You have to understand that in the context of designing a low radar observable body, EVERYTHING contributes to final RCS. If a structure, no matter how small like a rivet head or how large like a fin, is 'seen' by the radar, it is a contributor to that temporary RCS value as calculated by the radar computer. As the jet maneuvers, its RCS fluctuates because various structures' visibility changes. But as long as a structure have any chance of being exposed in the radar stream, it contributes to that RCS calculation.

If you think I used the word 'contributor' with no technical validity, think again...

https://www.science.gov/topicpages/r/radar+cross-section+rcs
Typical vehicle components are also discussed, together with their contribution to total vehicle RCS and their individual signature sensitivities.

Do you see the highlighted? Vehicle components -- like the canards -- adds up to total vehicle RCS.

When the J-20 maneuvers, the canards will move, no matter how slightly...

- Control of QUANTITY of radiators
- Control of ARRAY of radiators
- Control of MODES of radiation

...The canards will fall under rule two: Control of ARRAY of radiators.

If a canard moves just a few centimeters to maneuver the jet, any radar signal that exit that canard will impact nearby structure in different angles, changing 'total vehicle RCS', even if just for one second. We do not know it, but that one second maybe just long enough to reveal the J-20.

So when experts opined that the J-20's canards are negative to 'stealth', you may argue they are being hyperbolic, but they are not technically in error.


IR is not the solution to 'stealth' any more than the supposedly 'passive' radar can. As for AWACS, no one have more experience in using AWACS in combat than US and that includes how to evade AWACS.


Long wavelengths have been debated here before and I debunked their claimed efficacy many times over. When you broadcast in whatever long wavelengths, I will see you and take evasive measures before you can see me, to put it simply.

In your image, none of the jets are stealthy at all. In this angle Su-27, F15, J-20, F-22, F35 make no difference at all. You are exaggerating.

To be honest, I knew expert in China. They involved much deeper in Radar field, and stealthy design. You are just a user, like I am a user of cars.

Very disappointed. What you provided is inaccurate, not solid evidence, and a lot of things you can NOT explain at all.