F-22 vs J-20 - aka USA-made jet fighters vs China-made jet fighters

[Akasa]

The IAF is one of the most professional air forces around. And they are not known to lie to the public. China isn't anywhere near being India's sworn enemy, look elsewhere for that. In fact, it's the IAF that's at a disadvantage by claiming the J-20 is not stealthy enough.

Such as when they claimed that they defeated the RAF 12:0 during joint exercises? Come on now, this is getting ridiculous.

As for Luneburg lens:

I am sure the Flanker pilots know what you are talking about.

Please explain how IAF radar was able to distinguish an aircraft with Luneburg lens from one without.

Some of those Tibetan airfields are really close to the border. PLAAF was likely showing off to the IAF. Even if the J-20 was detected by a Su-30, the J-20 should still have demonstrated significant superiority to the IAF when it comes to detection ranges over the MKI.

I'd like to see photograph/satellite evidence that the J-20s have been operationally deployed to the Sino-Tibetan border. So far users and observers have been pretty good with following up on the deployment of J-20 units, but so far nothing has come up in the Tibet region.

The translation with the apparent body language was anything but "some". You can see it for yourself in the previous page. He simply dismisses the fact that the J-20 is a stealth aircraft itself.

All the more reason to dismiss those claims rather than to take them seriously.

 

[gambit]

You want me to be wrong so much, you put it as "partially wrong"? haha.

Because you were.

You were correct in that in radar detection, the target's RCS value and signature are largely unknown, which made this statement correct...

"I'm saying you don't need to know what it's radar signature to design a counter systems,..."

But you were also incorrect with that statement in that since each shape is unique it means that given the variations of a shape, all members of that group bears the same basic signature.

For example...

Which of the above pair would have similar RCS signature? Definitely not the second pair.

For the first pair, their foundation is the cube shape. There are four sides -- flat plates -- which means high specular reflections. For the second cube, its rounded edges means no edge diffractions, which means lower radar returns. So if we rotate both cubes, does not matter which speed and angle, the rounded cube would have a lower RCS overall, but both cubes would resonate with the regular incidences of high specular reflections precisely because of the four flat plates. This similarity would help identifying both bodies as being of the cube family.

All airliners have the same RCS signature, but not all fighters. On the other hand, fighters that have large delta wings like the Typhoon, Vigen, and Rafale WILL exhibit similar RCS signature at every radar aspect, most commonly the top and bottom views. These are the laws of physics that not even China can defy.

Thank you for your long paragraphs though.

I doubt you read it, let alone understood it, because as your next comment revealed...

You seems obsessed with one mode of radar tracking. Do me a favor and read about Pulse-Doppler radar.

My post about the MTI radar involved the Doppler component. Just because I did not insert the word 'Pulse' does not mean I do not know what I am talking about. The fact that you 'advised' me to read up on the PD radar means you did not read my response to your claim that extracting the Doppler component would be the easy way to counter 'stealth'. It is not, as I explained why FOUR YRS AGO. You are too late to the game. No serious minded and objective person on this forum argues that point anymore.

But if you separate out the clutter because it has a different Doppler spectrum and you do detection solely against noise, this is now a tractable problem.

For the readers out there, here is why, again...

- Every radar system have a clutter rejection threshold, usually based upon amplitude per return. The clutter rejection process immediately filters out any signal that is BELOW this threshold.

- This threshold can be lowered or even eliminated.

So if there are one million signals out there, it is a signal processing issue. Not a problem, but an issue.

A radar beam cannot process the entire visible area. Only a section at a time and that section is determined by the beam shape. So if there are one million signals, only a percentage, will be processed to filter out whatever criteria, which in this case is the Doppler component. The clutter rejection process filters out most, but now it is not used.

With a large beam, it is a time processing issue, as in each signal must be analyzed and compared to other signals in the batch.

With a small beam, it is a volume processing issue, as in volume of the sky to sweep.

It boils down to this...

CAPABILITIES
FEATURES

FUNCTIONALITY
EFFICACY

The last pair and with the last pair, it is the final half -- EFFICACY.

So while technically possible, using the Doppler component of a return signal to counter 'stealth' is TACTICALLY INEFFICIENT. You talk as if somehow in this little corner of the Internet, counter-stealth was revealed and no one from Lockheed and the USAF worked out the many possible scenarios in all these decades. We 'forgot' about the Doppler component of the return signal.

Oh yes, I'm not your average PDF member. I know how to google.

You are an average Chinese PDF member in the sense that you do not read the responses to your arguments and the sources you brought on from your googlling.

 

[Ultima Thule]

Sukhoi never claims stealth and jf 17 has no aes

Its not about JF-17 But J-20, How can your Sukhoi can detect/track/engage J-20 200 Km away @HariPrasad which is 5th gen jet and claiming serious threat to US in western Pacific, admitted by US top brass, Pentagon @HariPrasad

 

[Pepsi Cola]

LOL....

You are quite funny.

First of all, the question is this, how can you shoot down something when you do not know what kind of signature you are looking at.

You assume you know what you are looking for. But you don't. Hence how do you know what you are shooting down something, you don't know whether or not that is a F-22 or F35 or A Civilian Flight, you just indiscriminately shooting down EVERY radar contact you have. You know you shot down something but what?

On the other hand, F-22 or F-35 or any other Stealth Plane may or may not be shot down or even picked up by the radar. And the US wont tell you when and where they cross the border in China if US and China is at war.

So, just because your AA gun or SAM can shoot down anything that appear on your Radar, that does not mean it can shoot down Stealth Aircraft, because the main issue is, You Don't Know what you shot down. You assume that is a Stealth Fighter, but in reality, it can be anything, yes, it could be a Stealth Fighter, but it could as well be a passing jet or conventional fighter.

And in your example, along with IranAir 655 and MH-17, all those are the military of respective country ASSUME the target they are shooting down is a fighter/reconnaissance aircraft, that show you radar contact alone cannot distinguish between target.



The point is the "Design Reference" I am talking about, just because you are making transistor in a more advance method, that DOES not equal to that transistor is going to be superior than the one made with older method.

I7 is designed for high end gaming, i5 is designed on average usage, that is the design point. And if you don't like or don't get the i7 and i5 comparsion, how about Radeon Vx Vegas and GeForce 1080? Radeon Vx Vegas uses the latter moore's law, yet it still behind GeForce 1080, which is two generation ago.

And lol...….Your argument is "something better than nothing"?? That something is 1980 technology (yes F-117 was developed in 1980s) and even if you completely master that technology, that does not mean you know the characteristic of F-35 or even F-22 which is designed in mid-1990s.

And no, US bought Su-27 as a whole, not buying a wrecked Su-27, you cannot compare both situation.

Even gambit don't dare to say I'm totally wrong on this topic. That's because he knows I'm right. I'm definitely correct that you don't need to know an aircraft radar signature to design a system to shoot it down.

Radar signature really doesn't mean a lot. If you're unidentified, you'll get targeted.

If they are at an imminent war, the security would already be on high alert. Anything will get shot down without normal warnings. And yes, in times of war, "you just indiscriminately shooting down EVERY radar contact you have." However, as I've said before, all civilians aircrafts are required to have transponders and to identify themselves, if not they will get shot down. This protocol is common elsewhere in the world.

Comparing i5 and i7 is like comparing an advanced trainer to a fighter. Why are you doing this? Again, We're reaching the limits of Moore's Law, but if you look at the trend in the past, Moore's Law has always been right. Also, if it's not right, why would every make a big deal out of it? The trend is there for you to see in the graph I've provided you. It's clear as day, if you're still refusing it, I'm really just wasting my time.
At least gambit has real knowledge and he doesn't argue against facts, that I can deal with. lmao

How can I not compare? The point is you can study many stuff such as the stealth coating used on the aircraft even from wreckages. Ok you want better comparison?

" It’s similar to the MiG-15, in that we were looking at modeling and simulations, and developed threat assessments long before we got our hands on one.” During the Korean War, NASIC’s predecessor, the Air Technical Intelligence Center, recovered parts of crashed MiG-15s and studied the wreckage to learn more about that game-changing MiG’s performance." (airspacemag)

I really don't know why I have to spend so much time finding quotes to proof my points, which are relatively common sense. And to think that I started getting into this stuff years after you.

Because you were.

You were correct in that in radar detection, the target's RCS value and signature are largely unknown, which made this statement correct...

"I'm saying you don't need to know what it's radar signature to design a counter systems,..."

But you were also incorrect with that statement in that since each shape is unique it means that given the variations of a shape, all members of that group bears the same basic signature.

For example...

Which of the above pair would have similar RCS signature? Definitely not the second pair.

For the first pair, their foundation is the cube shape. There are four sides -- flat plates -- which means high specular reflections. For the second cube, its rounded edges means no edge diffractions, which means lower radar returns. So if we rotate both cubes, does not matter which speed and angle, the rounded cube would have a lower RCS overall, but both cubes would resonate with the regular incidences of high specular reflections precisely because of the four flat plates. This similarity would help identifying both bodies as being of the cube family.

All airliners have the same RCS signature, but not all fighters. On the other hand, fighters that have large delta wings like the Typhoon, Vigen, and Rafale WILL exhibit similar RCS signature at every radar aspect, most commonly the top and bottom views. These are the laws of physics that not even China can defy.


I doubt you read it, let alone understood it, because as your next comment revealed...


My post about the MTI radar involved the Doppler component. Just because I did not insert the word 'Pulse' does not mean I do not know what I am talking about. The fact that you 'advised' me to read up on the PD radar means you did not read my response to your claim that extracting the Doppler component would be the easy way to counter 'stealth'. It is not, as I explained why FOUR YRS AGO. You are too late to the game. No serious minded and objective person on this forum argues that point anymore.


For the readers out there, here is why, again...

- Every radar system have a clutter rejection threshold, usually based upon amplitude per return. The clutter rejection process immediately filters out any signal that is BELOW this threshold.

- This threshold can be lowered or even eliminated.

So if there are one million signals out there, it is a signal processing issue. Not a problem, but an issue.

A radar beam cannot process the entire visible area. Only a section at a time and that section is determined by the beam shape. So if there are one million signals, only a percentage, will be processed to filter out whatever criteria, which in this case is the Doppler component. The clutter rejection process filters out most, but now it is not used.

With a large beam, it is a time processing issue, as in each signal must be analyzed and compared to other signals in the batch.

With a small beam, it is a volume processing issue, as in volume of the sky to sweep.

It boils down to this...

CAPABILITIES
FEATURES

FUNCTIONALITY
EFFICACY

The last pair and with the last pair, it is the final half -- EFFICACY.

So while technically possible, using the Doppler component of a return signal to counter 'stealth' is TACTICALLY INEFFICIENT. You talk as if somehow in this little corner of the Internet, counter-stealth was revealed and no one from Lockheed and the USAF worked out the many possible scenarios in all these decades. We 'forgot' about the Doppler component of the return signal.


You are an average Chinese PDF member in the sense that you do not read the responses to your arguments and the sources you brought on from your googlling.

Please explain how does "since each shape is unique it means that given the variations of a shape, all members of that group bears the same basic signature." won't allow the Chinese to design an AA system against stealth aircraft? Because that's the whole point of my statement.

Oh yes I read it, I read a whole college lecture presentation on MTI radars on this, and many articles and forums just to come refute you. I did way more research than I even have to just to make sure I'm correct. lmao

I've provided you the quote from a reputable source to refute your claim, did you read it?

"So while technically possible, using the Doppler component of a return signal to counter 'stealth' is TACTICALLY INEFFICIENT." Great, I'm correct then that speed is is a discriminator for radar detection, especially when you get a more advanced radar that does Pulse Doppler processing. And as my source have also said, MTI does work. Im satisfied. I'm sure they have way better technologies now, I'm simply an military enthusiast and what's on the internet is what I have to work with.

My quotes refute your argument, I'm sorry you don't like it.

 

[Ultima Thule]

Even gambit don't dare to say I'm totally wrong on this topic. That's because he knows I'm right. I'm definitely correct that you don't need to know an aircraft radar signature to design a system to shoot it down.

Radar signature really doesn't mean a lot. If you're unidentified, you'll get targeted.

If they are at an imminent war, the security would already be on high alert. Anything will get shot down without normal warnings. And yes, in times of war, "you just indiscriminately shooting down EVERY radar contact you have." However, as I've said before, all civilians aircrafts are required to have transponders and to identify themselves, if not they will get shot down. This protocol is common elsewhere in the world.

Comparing i5 and i7 is like comparing an advanced trainer to a fighter. Why are you doing this? Again, We're reaching the limits of Moore's Law, but if you look at the trend in the past, Moore's Law has always been right. Also, if it's not right, why would every make a big deal out of it? The trend is there for you to see in the graph I've provided you. It's clear as day, if you're still refusing it, I'm really just wasting my time.
At least gambit has real knowledge and he doesn't argue against facts, that I can deal with. lmao

How can I not compare? The point is you can study many stuff such as the stealth coating used on the aircraft even from wreckages. Ok you want better comparison?

" It’s similar to the MiG-15, in that we were looking at modeling and simulations, and developed threat assessments long before we got our hands on one.” During the Korean War, NASIC’s predecessor, the Air Technical Intelligence Center, recovered parts of crashed MiG-15s and studied the wreckage to learn more about that game-changing MiG’s performance." (airspacemag)

I really don't know why I have to spend so much time finding quotes to proof my points, which are relatively common sense. And to think that I started getting into this stuff years after you.

And you don't know what is you talking about @Okarus , you arguing with professional without base, @gambit and @jhungary which knows better defense matters/concepts than you and me, And as for Moore's law is not related to military tech but toward civilian tech @Okarus

 

[Pepsi Cola]

Your 'scientific facts' are not applicable. Not that they are false, but simply not applicable to the subject at hand.

Here are the TRUE reasons why one complex system is superior to others...

CAPABILITIES
FEATURES

FUNCTIONALITY
EFFICACY

They are just as valid and powerful as any scientific principle. As I stated earlier, they are sorted in order of significance. A deficiency in capability will have an immediate effect on how a feature can perform. A deficiency in functionality will reduce efficacy, a desired outcome. A deficiency in the first pair will reduce the available options for the second pair. This is not component level design but system/process engineering. The Big Picture, if you will.


Actually, the FLCS does the flying to allow the pilot to become more a killer than a pilot.

I was told by an IP that with modern day fighters, if you want to enjoy flying, do it on your own time and dime, but the moment you strap into the cockpit of a modern day fighter, you must become a killer. The joy of flight is secondary. And he was correct. The USAF -- or any air force -- is a 'killer' organization. Defend by destruction, or at least the threat thereof.


Of course the move to the digital was needed. A digital avionics allows greater flexibility in terms of long term upgrades. Plus -- and this is reality talking -- the maker(s) of the analog avionics were either gone or leaving.


Do not pull that 'stating facts' on me. Of course you were trying to say the J-20 is 'superior' to the F-22, albeit in an offhanded way via the claim of superior electronics and Moore's Law.

Care to explain how a principle that governs all electronics does not have to do with J-20's radar? Can you explain why it's not applicable, because if you can't then it's better than your words without any proof or principles.

I didn't even used the word 'superior'. Go back and read.

If you're not gonna refute my points please don't make unnecessary comments, because I do read all of them and they're just wasting my time.

And you don't know what is you talking about @Okarus , you arguing with professional without base, @gambit and @jhungary which knows better defense matters/concepts than you and me, And as for Moore's law is not related to military tech but toward civilian tech @Okarus

I'm not professional. However I've made many good points, an refute many of gambit and jhugary's claims Am I wrong? Who are you to say that it is not related to military tech and just civilian tech? Please provide logical arguments.

I've spend this much time researching and debating, because I know I'm not wrong, and I am simply standing up for myself. Gambit said "MTI does not work", I provided a quote from a reputable defense contractor that says it works. Now he's walking back on his statement and simply say that using these kinds of method to assess speed is "tactically inefficient." Are you saying I should not do this?

 

[Ultima Thule]

I'm not professional. However I've made many good points, an refute many of gambit and jhugary's claim? Am I wrong? Who are you to say that it is not related to military tech and just civilian tech? Please provide logical arguments.

What good points i seen your debate to @gambit and @jhungary from the beginning, you haven't single good point @Okarus


every think we have use to i mean especially electronics and its big items develop and tested by military before its enter the civilian markets prime examples were ENAAC the first computer develop by USA in 1941 to predict German BM trajectories of the world war 2 & Boeing 747 which was first contested of LM design and become most successful airliner of the world & GPS originally designed for US armed forces but later used by civilian companies and individuals @Okarus

 

[Pepsi Cola]

What good points i seen your debate to @gambit and @jhungary from the beginning, you haven't single good point @Okarus


every think we have use to i mean especially electronics and its big items develop and tested by military before its enter the civilian markets prime examples were ENAAC the first computer develop by USA in 1941 to predict German BM trajectories of the world war 2 & Boeing 747 which was first contested of LM design and become most successful airliner of the world & GPS originally designed for US armed forces but later used by civilian companies and individuals @Okarus

Oh haha I've made a lot of points they can't refute, those are what I think as "good". They've been trying to say I'm wrong, but without substance, hence "partially wrong". But these are simply for my personal entertainment. You can think whatever you want.

Here let me use gambit's words to refute your argument.

FYI...The base technologies in military hardware is preferably at least 5 yrs behind the civilian sector. For US, we are conservative so we want 10 yrs of civilian debugging before we will risk our pilots' lives. The SR-71 have a mystique to be an aircraft of esoteric technologies aided by the secrecy about it, when in reality, literally %90 of the jet is dated back to the 1950s.

The point is military and civilian market constantly exchanges technologies and they are not far from each other. In some areas, military might have more advanced technologies, but for some areas the civilian markets also have more advanced (more mature) technologies. Good point?

 

[Ultima Thule]

"FYI...The base technologies in military hardware is preferably at least 5 yrs behind the civilian sector. For US, we are conservative so we want 10 yrs of civilian debugging before we will risk our pilots' lives. The SR-71 have a mystique to be an aircraft of esoteric technologies aided by the secrecy about it, when in reality, literally %90 of the jet is dated back to the 1950s."

The point is military and civilian market constantly exchanges technologies and they are not far from each other. In some areas, military might have more advanced technologies, but for some areas the civilian markets also have more advanced (more mature) technologies.

you all wrong Military departments of the world want a tech far more better/finer than civilian sector, if even military want civilian tech infact they quite different from those civilian tech, base tech for civilian sector/ standards had been developed by defense departments/agencies of 50s, 60s, 70s and 80s @Okarus

 

[Yaseen1]

u.s did mistake by choosing f22 over f23 as 5 gen plane due to lower cost.f23 would have given more superiority to u.s over rivals

 

[gambit]

I'm not professional. However I've made many good points, an refute many of gambit and jhugary's claims Am I wrong? Who are you to say that it is not related to military tech and just civilian tech? Please provide logical arguments.

I've spend this much time researching and debating, because I know I'm not wrong, and I am simply standing up for myself. Gambit said "MTI does not work", I provided a quote from a reputable defense contractor that says it works. Now he's walking back on his statement and simply say that using these kinds of method to assess speed is "tactically inefficient." Are you saying I should not do this?

You have 'refuted' nothing of my responses to you, and I have not 'walked back' any statement. When I said the MTI method does not work, I meant it in the context of what people claimed that the method WOULD be a viable tactic against low radar observable platforms. So far, you managed to dredge up one OPINION, not anything remotely like an experiment that could serve as a foundation for a future defense method.

 

[randomradio]

Such as when they claimed that they defeated the RAF 12:0 during joint exercises? Come on now, this is getting ridiculous.

Strictly speaking, the IAF was never quoted saying that. It was written by Vishnu Som, an extremely important person in the news media in the country.

Please explain how IAF radar was able to distinguish an aircraft with Luneburg lens from one without.

Radars see hotspots. It's easy to see if the radiation is coming in from hotspots or from the Luneburg lens.

You can see the returns from different parts of the aircraft here:

Just look at page 4.

If the J-20 had Luneburg lens on, it's easily identifiable.

Plus, unlike most air forces, our pilots are trained EW officers as well, not to mention the MKI almost always has the WSO with more than a decades worth of experience.

I'd like to see photograph/satellite evidence that the J-20s have been operationally deployed to the Sino-Tibetan border. So far users and observers have been pretty good with following up on the deployment of J-20 units, but so far nothing has come up in the Tibet region.

Detachments always fly out to different places. It's part of the training regimen also. So it's not necessary for an aircraft to be stuck within its home base.

Not to mention, India is China's biggest threat because we are the only country around with the army capable of invading China. It's obvious J-20 will be tested against our systems.

All the more reason to dismiss those claims rather than to take them seriously.

Not really. That's the Air Chief there, not some random guy.

 

[Pepsi Cola]

you all wrong Military departments of the world want a tech far more better/finer than civilian sector, if even military want civilian tech infact they quite different from those civilian tech, base tech for civilian sector/ standards had been developed by defense departments/agencies of 50s, 60s, 70s and 80s @Okarus

Tell that to @gambit

Gambit is right that most hardwares and technologies already existed and tested in civilians market. The cutting edge technologies you hear so much is just a part of the big picture. Those little components and hardware technologies still come from civilians markets.

Hey, and why are you telling that I'm all wrong when I'm simply using gambits words to refute your argument.

You have 'refuted' nothing of my responses to you, and I have not 'walked back' any statement. When I said the MTI method does not work, I meant it in the context of what people claimed that the method WOULD be a viable tactic against low radar observable platforms. So far, you managed to dredge up one OPINION, not anything remotely like an experiment that could serve as a foundation for a future defense method.

How am I supposed to know what context you're talking about? I was saying that speed is a compromising factor, and it is (my source agreed). You brought up the rather irrelevant MTI radars yourself.

Moore's Law is based on observed trend of all electronics and it's widely accepted as the prevailing principle in the electronics industry. To base military advancement on this law is my opinion, and it's an opinion that no one has yet to able to refute with substance and say why would military electronics won't follow it.

Here I'll give you an article from phys.org to further clarify what Moore's Law really entails

"
Moore's Law has been a great blessing to science and mathematics research. Modern laboratories are loaded with high-tech measurement and analysis devices, which become more powerful and cheaper ever year.

In addition, a broad range of modern science, mathematics and engineering has benefited from Moore's Law in the form of scientific supercomputers, which are used for applications as diverse as supernova simulation and protein folding to product design and the processing of microwave background radiation from the cosmos.

Software running these computers has advanced abreast with Moore's Law.

For example, the fast Fourier transform algorithm, which is used extensively in scientific computation, and magnetic resonance imaging (MRI), both involve substantial computation that would not be possible without Moore's Law advances.

It is not entirely coincidental that both of these algorithmic advances arose roughly 50 years ago, the same time Moore's Law was first observed.



Read more at: https://phys.org/news/2015-07-law-years.html#jCp"

 

[gambit]

Please explain how does "since each shape is unique it means that given the variations of a shape, all members of that group bears the same basic signature." won't allow the Chinese to design an AA system against stealth aircraft? Because that's the whole point of my statement.

This is proof that even though you read, you did not understand.

An RCS value is not the same thing as an RCS signature.

Look at this illustration again...And try to spend more than just one second at it...

A 'signature' is unique in the sense that it contains features that nothing else has, whereas a value is just a numerical assignment.

Look at it this way...

Two men have the same name of 'John Smith', but would their handwritten signatures be exact? No. The value of their common name would be the same of 4 for 'John' and 5 for 'Smith'. But it would take an expert forger to sign their names exactly the same way.

So you did not understand what I responded to you. I did not say it "won't allow". In fact, I gave you the clue as to how signatures WOULD -- not could -- be used as a viable counter-stealth method. I said: "All airliners have the same RCS signature, but not all fighters. On the other hand, fighters that have large delta wings like the Typhoon, Vigen, and Rafale WILL exhibit similar RCS signature at every radar aspect, most commonly the top and bottom views."

You gave an overly broad claim in post 46 pge 4: "so I'm saying you don't need to know what it's radar signature to design a counter systems,..."

I gave you an explanation on why an RCS signature, not an RCS value, is needed.

Oh yes I read it, I read a whole college lecture presentation on MTI radars on this, and many articles and forums just to come refute you. I did way more research than I even have to just to make sure I'm correct. lmao

I've provided you the quote from a reputable source to refute your claim, did you read it?

I understood it better than you have and can. But did you understood what I said about beam width and how much a radar can process at any moment? Guess not since you are still harping on the buzz words 'Pulse Doppler' and quoting someone from quora.com.

 

[Ultima Thule]

OTE]

Tell that to @gambit

Gambit is right that most hardwares and technologies already existed and tested in civilians market. The cutting edge technologies you hear so much is just a part of the big picture. Those little components and hardware technologies still come from civilians markets.

Hey, and why are you telling that I'm all wrong when I'm simply using gambits words to refute your argument.

Hi don't twist your words, I continuously following your and @gambit debates @gambit didn't said ahow me his post number or copy paste his post @Okarus