Official Chengdu J-20 Discussion Thread

Sampanviking

Banned Member
Ok, so people are getting hung up about what we cannot say about this Plane based simply on a few taxi way photos. Actually, I agree but I also think there is a lot more that can be given a pretty good shot at, by simply looking at the bigger picture.

First off, I would not be disparaging about any major aircraft manufacturer and can only acknowledge their respective mastery of their craft. Each is I am sure competent and produces aircraft capable of performing the tasks required of them.

That being said, they are different companies and will therefore approach problems differently, in accordance with their past experience and their innate strengths and weaknesses. There are; no doubt, deep differences in doctrine between the Governments that these companies serve. In the US we get the impression that the aircraft must have required capability at any cost, while in China, this is more nuanced and cost control is given a higher priority even at the expense of capability.

One thing I have learned from dealing with Chinese companies in general is that they look at problems differently than do most Western companies. I doubt very much if Chinese Aircraft Manufacturers think in terms of “generation” when they come to design capability at the right price, but rather look at a range of technologies and capabilities that they wish to counter, neutralise and/or defeat. Part of this of course is a function of catch up, which means that the Chinese already have a target to aim for, while the US companies seem to be putting together the latest technologies and seeing what they get. The Chinese by contrast will not disregard a technology that is effective and cost efficient simply because it is not of “this generation”.

I would also be wary of looking at the design function purely through the prism of Western eyes. As others have mentioned Stealth is an amalgamation of different technologies and techniques and the Chengdu are likely to have strengths and weaknesses across the spectrum of these. In addition, given the level of innovation shown recently by Chinese companies in many industrial areas, where they now define the cutting edge, you should not discount that Chengdu have their own areas of innovation ahead of the rest. I would also add that the characteristic of completing projects ahead of time and under budget is a general Chinese strength not to be underestimated.

All of this adds up to the Chinese being likely to have produced an aircraft with a very particular objective in mind, rather a general technology demonstrator.

So, what have we got?
We have a large twin engine jet that is appears designed to monopolise on Stealth and range. It looks rather expensive compared to other Chinese planes and so I think it is a fair assumption that it would not be used for roles that would compromise the Stealth Advantage.

But what would that be?

I think the best answer is to look at the current and anticipated PLAAF inventory and see where it is most likely to best fit in.

The next thing to do is to look at the PLAAF planes that are top of the queue for withdrawal and replacement.

These are:
J-7 and J-8 Interceptors
Q5 – Ground Attack
H6 - Bombers

The new Aircraft seems a poor fit for any of these niches – wasted as a fast defender interceptor and losing its stealth advantage carrying externally mounted Ground Attack Munitions and with nothing like the carrying potential of the H6

Is then the new plane intended to replace something in or compliment the current front line tactical line up?

China’s front line is largely made up of highly capable aircraft from the Flanker and J-10 families, most are still new, effective multi strike and multi role aircraft capable of carrying significantly higher weapon payloads than that which can be carried in the internal bay of a Stealth Fighter. While some of the older Flankers may start to be rotated down from front line to replace older defenders, there is still no obvious fit for the J-20 to replace an existing niche currently occupied by these planes.

So, it looks like a new niche, but what is it?

As previously stated, the current front line of J-10’s and Flankers are very capable aircraft capable of carrying out the vast majority of China’s air defence needs, with one notable exception - having to penetrate enemy territory defended by Stealth Fighters.

To fill this gap, China would need a long distance, long endurance Air Superiority Fighter which capitalised on Stealth to ride shotgun for the Strike Aircraft, hunt the hunters and carry primarily Air to Air Munitions.
I believe that the J-20 is indeed that plane. I would further deduce that given the likely cost of the aircraft and its very particular mission, that numbers intended for service will be in the very low hundreds if indeed barely breaking into triple figures.

I also suspect that “Stealth” is not going to be a fundamental requirement of all new Chinese Aircraft, not at least until the cost of the technology is considerably reduced.
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
So, what have we got?

But what would that be?
All of what you have said is basically what I and others have said not only on here but also on other forums.

you assume much by stating that we only look at it through "western eyes".

1) not everyone who has commented is a westerner
2) countries tend to have analysts and engineers from other countries working for them.

eg most of the senior military scientists that I deal with are Indians who now have australian citizenship, a significant number of young engineers in australia are ex chinese and.indian nationals - and there's no shortage of them in australian defence

I've seen the same in other large countries with significant military budgets....

the "westerners" don't understand "easterners" logic is a furphy....
 

Wang Dong

New Member
gf0012

Is there a good online article or journal paper where we can read an overview about signal management and aircraft design. My background is not engineering but mathematical modeling and simulation, and some of the stuff you have been saying rings a bell, but I can't quite connect the dots.

Furthermore, how hard would it be to write a very rough simulator that represents a basic model of the airframe or a surface on the airframe, how it reflects different signals, and how it is perceived by different observers, just to get an idea. Or are there too many other variables.
 
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gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
gf0012

Is there a good online article or journal paper where we can read an overview about signal management and aircraft design. My background is not engineering but mathematical modeling and simulation, and some of the stuff you have been saying rings a bell, but I can't quite connect the dots.
nothing online that I know of. however, published material references:

Introduction to RF Stealth
David Lynch, Jr.
Hardcover, 560 pages
ISBN10: 1891121219
ISBN13: 9781891121210
Publisher: SciTech Publishing,

and:
"The Radar Game, Understanding Stealth Aircraft and Survivability" I don't have it at my current location, so you will need to do a google. :)



Furthermore, how hard would it be to write a very rough simulator that represents a basic model of the airframe or a surface on the airframe, how it reflects different signals, and how it is perceived by different observers, just to get an idea. Or are there too many other variables.
I seriously doubt it, not without reference to all the data on signals, materials issues, shape vectors, emission vectors etc.....

hence my absolute contempt for APA when they claim to have designed a program "at home" etc....
1) none of those idiots have any clearances to see relevant material on signal management issues and conditions
2) if they had clearances in the past then they well know that unless its already released as cleared by the host country - then its a criminal offence to publish detail. If its released then its fundamentally worthless as that process is now dirty and uncontrolled, which means that the host obviously has workarounds and doesn't see it as compromising their forces and assets. considering that some of the response capability of the converted Iowas is still classified, that some of the proximity results from the 60's on MBT's is still classified, then whats the chances of real meaningful data about sig management on real platforms being available to the general public... IOW. APA are full of crap (simple english to make the point :))
3) there's no way that an assessment done even off a 3D wire will provide coherent results. thats why real tests are via pole mount assessments and include anechoic tests - none of which will have publicly releasable data.
4) the number of variables to consider is just mind boggling.

I'm quite comfortable in stating that the people who claim to be able to do so are engaging in intellectual onanism....
 

jack412

Active Member
opssg, thanks for the updated link on the radar game
refer to opssg link for radar game below
 
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Todjaeger

Potstirrer
One thing I have learned from dealing with Chinese companies in general is that they look at problems differently than do most Western companies. I doubt very much if Chinese Aircraft Manufacturers think in terms of “generation” when they come to design capability at the right price, but rather look at a range of technologies and capabilities that they wish to counter, neutralise and/or defeat. Part of this of course is a function of catch up, which means that the Chinese already have a target to aim for, while the US companies seem to be putting together the latest technologies and seeing what they get. The Chinese by contrast will not disregard a technology that is effective and cost efficient simply because it is not of “this generation”.
Just a bit of a correction seems in order here.

While there is no universally agreed to set of definitions for modern fighter aircraft generations, here is a pretty good list of the generations, the time periods for the generations, aircraft of those generations, and what characteristics made aircraft fit within a particular generation.

Aerospaceweb.org | Ask Us - Fighter Generations

IMO, what really determines which generation a particular fighter belongs to is the capabilities within the aircraft. And in terms of what sorts of fighters US/Western aerospace companies develop, that is set by either the markets they are designing for and/or domestic customers are requesting. In short, the capabilties come first. Once a given set or range of capabilities is chosen, then aircraft meeting those capabilities could be considered to be a part of that particular fighter generation, unless of course it is sufficiently capable/advanced to belong to a later generation.

By way of example, if Boeing for some reason assigned engineers today to design a new jet fighter that was functionally the equivalent to a WWII-era Me-262, even down to materials used in the aircraft, the resulting Boeing fighter would be a 1st generation fighter jet. Even though it would be a brand new design, from a manufacturer with a history of designing aircraft.

The generation does not determine the capabilities of a fighter, it is the capabilities which determines the generation.

-Cheers
 

weasel1962

New Member
Re:

Just a bit of a correction seems in order here.

While there is no universally agreed to set of definitions for modern fighter aircraft generations, here is a pretty good list of the generations, the time periods for the generations, aircraft of those generations, and what characteristics made aircraft fit within a particular generation.

Aerospaceweb.org | Ask Us - Fighter Generations

IMO, what really determines which generation a particular fighter belongs to is the capabilities within the aircraft. And in terms of what sorts of fighters US/Western aerospace companies develop, that is set by either the markets they are designing for and/or domestic customers are requesting. In short, the capabilties come first. Once a given set or range of capabilities is chosen, then aircraft meeting those capabilities could be considered to be a part of that particular fighter generation, unless of course it is sufficiently capable/advanced to belong to a later generation.

By way of example, if Boeing for some reason assigned engineers today to design a new jet fighter that was functionally the equivalent to a WWII-era Me-262, even down to materials used in the aircraft, the resulting Boeing fighter would be a 1st generation fighter jet. Even though it would be a brand new design, from a manufacturer with a history of designing aircraft.

The generation does not determine the capabilities of a fighter, it is the capabilities which determines the generation.

-Cheers
Agreed. Generation is irrelevant except to the marketing people trying to distinguish their product from the competitors.

How does one classify an F-117 that had stealth but little else as compared to a F-15SE that has single aspect stealth but almost everything else?

Monoplanes got shot down by biplanes until pilots figured out not to enter into a maneuvering fight with those. Same reason why P-51s downed Me-262s.

Pilots understand the strength and weakness of each aircraft they pilot. Utilise the strengths, avoid the opponent taking advantage of the weakness. Fighter pilots don't really care which generation their aircraft belongs to.
 

Feanor

Super Moderator
Staff member
Agreed. Generation is irrelevant except to the marketing people trying to distinguish their product from the competitors.

How does one classify an F-117 that had stealth but little else as compared to a F-15SE that has single aspect stealth but almost everything else?

Monoplanes got shot down by biplanes until pilots figured out not to enter into a maneuvering fight with those. Same reason why P-51s downed Me-262s.

Pilots understand the strength and weakness of each aircraft they pilot. Utilise the strengths, avoid the opponent taking advantage of the weakness. Fighter pilots don't really care which generation their aircraft belongs to.
The F-15SE would be a very late 4thgen (4.5+ gen) in my opinion, being borderline. The F-117 imo isn't a fighter jet. It's a tactical bomber.
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
Agreed. Generation is irrelevant except to the marketing people trying to distinguish their product from the competitors.
The definitions I received 5 years ago were from NASA staff based at White Sands. Thats the definition I gave to Kopp at the time

How does one classify an F-117 that had stealth but little else as compared to a F-15SE that has single aspect stealth but almost everything else?
considering that the F-117 was deliberately developed for a mission intent, then VLO was the key - "stealth" never came into the definition of generations. Generations cover a multitude of transitional capabilities

Monoplanes got shot down by biplanes until pilots figured out not to enter into a maneuvering fight with those. Same reason why P-51s downed Me-262s.
they were still a functional generation behind in development terms. the lesson then was skill and hubris - the same as today

Pilots understand the strength and weakness of each aircraft they pilot. Utilise the strengths, avoid the opponent taking advantage of the weakness. Fighter pilots don't really care which generation their aircraft belongs to.
I can tell you that those who have flown in or gone up against the F-22 from RAF and RAAF certainly do - and they're pilots with 6000 plus hours and are rated combat trainers.

maybe the average cessna pilot doesn't care, but a bum in the seat does not always provide an edge. I think you misunderstand the significance of the change in situational appreciation and awarness and the power of those management systems on the aircraft like the F-22.
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
The F-15SE would be a very late 4thgen (4.5+ gen) in my opinion, being borderline. The F-117 imo isn't a fighter jet. It's a tactical bomber.
The F-117 actually ended up creating a new capability set, it was tactical strike as opposed to bombing. they elevated and enhanced the delivery of PGM's

agree on the F-15SE
 

weasel1962

New Member
Re:

I can tell you that those who have flown in or gone up against the F-22 from RAF and RAAF certainly do - and they're pilots with 6000 plus hours and are rated combat trainers.

maybe the average cessna pilot doesn't care, but a bum in the seat does not always provide an edge. I think you misunderstand the significance of the change in situational appreciation and awarness and the power of those management systems on the aircraft like the F-22.
I can't comment on all pilots but that's the view from some of the pilots I've spoken to (which don't fly in an air force that has F-22s).

Situational awareness is definitely important but again is a generation label necessary to define the difference (notwithstanding that its a NASA source)?

In the air dominance role, you are definitely aware that a single fighter won't go into battle without support (though it might have to). How much will situational awareness differ for a F-15E equipped with TEWS + AEW support compared to a F-22?

I don't think its a question of misunderstanding how important situational awareness is but how important a network environment really is. It has been long argued that a network environment acts as a value add to improve the combat capabilty of a single weapon. Whilst your focus has been on the fighter itself, the fighter pilots I know focus on the network and network coordinated fighter tactics.

Even using the jargon, how would a fifth gen fighter with a 4th gen network fare going up against a 4th gen fighter with a 5th gen network?

"stealth" never came into the definition of generations.
Really? On that... I'm surprised. I keep reading about Gates making references to Russki and Chinese fifth gen fighters in his speeches and the presumption has always been that all-aspect stealth is probably the main defining factor for what qualifies as an aggressor fifth gen fighter. Or does Gates also misunderstand what a fifth gen fighter is?

By your definition, China, being a generation behind, is therefore currently only developing its 4th generation fighter ie the J-XX? I'm not so sure DoD follows your (or NASA's) definition as closely.

I think, NASA's definition aside and your objections noted, the general public has accepted that a perceived stealth design is indicative of a fifth generation jet (notwithstanding the actual differences in capability).

Good luck trying to convince a billion chinese that their jet isn't a 5th gen fighter. I am more inclined to accept Gates' statement that in 2020 the USAF will probably still have numerical and qualitative dominance in terms of 5th gen fighters and leave it as that.
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
I can't comment on all pilots but that's the view from some of the pilots I've spoken to (which don't fly in an air force that has F-22s).
which is why I'm making comment about people who have either flown them (RAF and RAAF) and who have gone up against them in DACT. AFAIK thats only 4I's pilots

Situational awareness is definitely important but again is a generation label necessary to define the difference (notwithstanding that its a NASA source)?
I think it is because you're talking about transitional and transformational technologies. What I've invariably seen is people from some countries disparaging "stealth" but as soon as their own country develops what they regard as a "stealth" capability, they change their tune - so call me cynical about motives for some posters....

In the air dominance role, you are definitely aware that a single fighter won't go into battle without support (though it might have to). How much will situational awareness differ for a F-15E equipped with TEWS + AEW support compared to a F-22?
significantly, because the F-22 is able to enhance the overall sensor picture. those things on the leading edges are not about boundary layer management... :)


I don't think its a question of misunderstanding how important situational awareness is but how important a network environment really is. It has been long argued that a network environment acts as a value add to improve the combat capabilty of a single weapon. Whilst your focus has been on the fighter itself, the fighter pilots I know focus on the network and network coordinated fighter tactics.
no doubt you have seen me go purple elsewhere trying to explain to all and sundry that "its about the system stupid" - not the platform as a single uber entity

Even using the jargon, how would a fifth gen fighter with a 4th gen network fare going up against a 4th gen fighter with a 5th gen network?
thats hard to say in the sense that the only nation with multi generational history of fielded manned and unmanned VLO and LO is the US - which country in the world comes remotely close to having multi-theatre concurrent sensor ability at a CEC level? No one remotely comes close. So the question can't be literal.


Really? On that... I'm surprised. I keep reading about Gates making references to Russki and Chinese fifth gen fighters in his speeches and the presumption has always been that all-aspect stealth is probably the main defining factor for what qualifies as an aggressor fifth gen fighter. Or does Gates also misunderstand what a fifth gen fighter is?
I'd be placing my money on what comes out of Dryden before I'd takes Gates definition. Politicians do like to dumb the debate down to sound bite denominators, the general public would be glazing over at the 2 minute mark. All the material that we see on future force structure deals with VLO and LO as a component element in future airforce and airfighting structure. Its one tool, but its a significant tool if you own the space and have it populated with your sensor grids, be they unmanned (GHawk), manned (Compass, Rivet, Guard etc...), CEC capability (Aegis), cross service comms and data shift (Link16, Link22) and atmospheric - out to space based radar. eg the USN alone has a bigger satellite constellation footprint capability than the russians - and the russians are a golden mile ahead of the chinese.

hence, you can't dumb it down because reality has to hit the raod somewhere.

By your definition, China, being a generation behind, is therefore currently only developing its 4th generation fighter ie the J-XX? I'm not so sure DoD follows your (or NASA's) definition as closely.
Dryden is White Sands. they're co-located with USAF T&D out of necessity. I'm pretty sure that NASA and USAF have a clue considering that they've been instrumental in force development concepts. all other countries are at the white paper level. The US has just retired its first generation VLO asset after being in service for 25 years.. IMO China is a generation behind in a number of technology sets, just because you trot out a cranked delta and canted skegs does not mean that you have mastery of VLO development. I've already clearly stated why there are too many inconsistencies in the platform for me. However, they should be and are justifiably proud of it.

I think, NASA's definition aside and your objections noted, the general public has accepted that a perceived stealth design is indicative of a fifth generation jet (notwithstanding the actual differences in capability).
and thats due to an indolent media rather than whats accepted in the community. thankfully I don't get my technical input from newspapers (or APA for that matter)

the general public doesn't know the difference between an M113 and a tank, a frigate and a cutter, an LHA and a CVN. thats hardly the yardstick that we should measure proper assessment by.
 

Feanor

Super Moderator
Staff member
The F-117 actually ended up creating a new capability set, it was tactical strike as opposed to bombing. they elevated and enhanced the delivery of PGM's

agree on the F-15SE
Either way the argument on generations doesn't apply.
 

gf0012-aust

Grumpy Old Man
Staff member
Verified Defense Pro
Either way the argument on generations doesn't apply.
of course it does, its about all those capabilities within a platform designed at inception. Its why people are so desparate to add iterative tags like 4.5 to make them fit on the timeline

if people consider that pistons and jet fighters was not a developmental separation and transformational construct, then there's not much we can do about

some people still think the earth is flat.

whether people like it or not, officially, within militaries themselves, we use those terms because they have meaning

if others don't want to accept it then tough, they aren't doing force development, or future planning. its part of our lexicon - not because its a buzz word, but because it allows us to define stages in future force constructs etc... it has significant impact on doctrine definition and development.

seriously, if the general public don't want to accept it then I for one don't care 1 iota because they aren't responsible for what gets brought to the table, why we buy certain system capabilities and why we have a definite plan.

5th gen aircraft are part of that. and if people seriously think its just marketing hype and don't see that its militarys that are employing the definitions for a reason - then what more can I say.

Its a wasted debate, I'm not even going to remotely further the debate because they're not serious, don't understand the big picture, and usually are letting national pride interfere with reasoned debate.

ignore what the manufacturers say - look at the systems and force development issues. The F-15SE is no more 5th gen than the SHornet, Boeing claim that both are. only a blind teenager would accept that they are.. Sooner or later, proper military based analysis should be invoked. If its not then its just pretend analysis.
 

weasel1962

New Member
Even using the jargon, how would a fifth gen fighter with a 4th gen network fare going up against a 4th gen fighter with a 5th gen network?
thats hard to say in the sense that the only nation with multi generational history of fielded manned and unmanned VLO and LO is the US - which country in the world comes remotely close to having multi-theatre concurrent sensor ability at a CEC level? No one remotely comes close. So the question can't be literal.
Thanks for the responses.

I think it could be a significant question when applied to countries like Korea and Japan for resource allocation. Personally, I don't see either accepting an argument that its 4th or 4.5 generation fighters can adequately deal with the perceived chinese threat so long as they continue to upgrade their network capabilities.

I would think they would seek next gen fighters that are both numerical and qualitatively comparable or exceed the potential (rather than actual) capabilities of the chinese.

The APA drumming how F-35s aren't really fifth gen really doesn't help.

Its like arguing a single engined F-16 can take on a twin engine Mig or Suk. The pilots know it can be done. But some politicians get swayed and think maybe the F-15 is needed instead...

Now the equivalent today is the F-35 (for the F-16), F22 (for the F-15) and the Mig/Suk = J-XX/T-50.
 
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jack412

Active Member
well if this is right, it means Kopp &co and bill might have to start their j-20 spams again
Taiwan questions China's stealth capability - CNA ENGLISH NEWS

Pictures purporting to be of the prototype J-20 stealth fighter were posted on several websites after the U.S.-based Aviation Week magazine reported that the aircraft had been undergoing taxiing tests in late December at an airfield in Chengdu, western China.

The debut of the J-20 was announced in November 2009, but Shen I-ming, deputy defense minister in charge of intelligence, anwering questions from Legislator Lin Yu-fang of the ruling Kuomintang (KMT) before the Legislative Yuan's Foreign and Defense Committee, said the authenticity of the photos was questionable.

Shen confirmed that China has been developing its fifth-generation fighters but said the aircraft shown in the photos do not appear to be that system.
 
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