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Photos and analysis of China's J-20 fighter as it nears first flight

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Matej

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Wil said:
Is this the Father (or Mother) of Mig 1.44 and J-20?
As the HiMAT is the pure US construction, how will you evaluate the probability that it was used as the basis for the 5th gen fighter of both US competitors? Not to mention, that this subscale research model flew in many (really many) different configurations? When you posted the NASA links to the photos, you really should read also their description.
 

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Foxglove said:
This has been an astounding year with the T-50 and J-20 revelation. I only hope that 2011 will be just as exciting. Happy New Year all!
I second that , hope 2011 will be at least as exciting . I saw rumours around that J-20 might even had flown on the 31st ( today), but it seems its not confirmed . Other rumours are that the thing might have been spotted at the CAC airfiled as far back as November , but those who claimed to have seen it were not believed at first. Cant wait for some vids of the bird , seems there are SOME out there to be released...hopefully soon!

Happy New Year to everyone :)!
 

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sealordlawrence said:
You have to have developed something in order to be able to unveil it, even if it is just an airframe with some engines in it. The idea that this was unveiled due to a paper agreement between Russia and India is preposterous.
Yes, I agree. I think the critical point is that the thing could have been sitting in a hangar (or even test flown) and the actual appearance of photographs in the public press may have been deliberately timed.
 

Wil

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Hi!

A good comparison (I think...) between J-20 and F-22 Raptor.

J-20 Length = ~21.11 m (****Provisional****)



http://img208.imageshack.us/img208/2818/j20f22comp.jpg

Good 2011!!

;)
 

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Wil

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Matej said:
Wil said:
Is this the Father (or Mother) of Mig 1.44 and J-20?
As the HiMAT is the pure US construction, how will you evaluate the probability that it was used as the basis for the 5th gen fighter of both US competitors? Not to mention, that this subscale research model flew in many (really many) different configurations? When you posted the NASA links to the photos, you really should read also their description.
Dear Matej,

It seems to me Mig 1.44 has the same configuration of NASA Himat (canards, delta wing, etc).

HIMAT + Mig 1.44 + F-22 + F-35 = J-20 (!!)

;)
 

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In November 2009 PLAAF Deputy Commander General He Weirong gave the interview, where he stated that their own 5th generation fighter will fly soon and will enter service between 2017 and 2019. It means that what we are seeing now is in general according to the plan. I agree with the assumption that the decision to allow the aircraft to perform the taxi tests in front of the general public was largely meaned as the response to the Indo-Russian agreement. At least it makes sense.

Will: to answer you in the same style: apple + plum will not produce the mango.
 

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It doesn't look to me like HIMAT has a delta wing, but a swept wing. Does it really make sense tho, to consider 5th gen a/c would be based on a 30+ year old demonstrator?
 

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Wil said:
Hi!

A good comparison (I think...) between J-20 and F-22 Raptor.

J-20 Length = ~21.11 m (****Provisional****)



Good 2011!!

;)
Your F-22 is reversed. But you know that already. -SP
 

Sundog

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The J-20 has as much to do with the HiMAT demonstrator as the F-22 does the MiG-21; after all, they're both basically tailed delta's. Seriously, just stop the ignorance now, please. There is a given state of technological development and from the basic requirements set forth there are only so many useful solutions to the problem. For the Chinese it is a twin engined canard delta layout.
 

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Well. Without going into too much detail, there are a number of ways that you can discern the dimensions of the aircraft from a good set of photos.
With those dimensions, you can inspect some of the features of the aircraft in detail. In particular, you can look at the sawtooth edges on the landing gear doors. Since plain old antenna theory applies here, by knowing the size of those sawtooths and their alignment you can get a pretty good idea of what frequencies, and thus what type of radar, they are trying to counter.
As a test here you could look at the original Lockheed XST design, which was optimized to counter the GUN DISH radar.

The ARRL Handbook covers enough antenna theory and practice for someone to get started understanding how this works.
If you know what radars, or bands the aircraft is optimized for, that can tell you a lot about its purpose. Western aircraft face a broad range of threat frequencies and radar types, but the threat systems are obtainable - there is a large portion of Nevada filled with these systems. The Chinese on the other hand possibly see themselves facing a narrower range of potential threat radars, and many of those may be very difficult to obtain or replicate on a range.

I still say it is an espresso machine.
 

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Orionblamblam said:
It's the mirror universe F-22. Look closely and you'll see that the pilot has a goatee.
Oh, God.
Your agonizer, please, Mr. Lowther.
 

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Teal Groups aviation expert Richard Aboulafia gives his F-35 v. J-20 "quickie" analysis (from Defensetech.org)

I would gauge a modern combat aircraft’s capabilities by looking at the following features:

1. Access to offboard space, ground, and air-based sensors, particularly a capable AEW/AWACS system with a well-trained crew and robust data links.

2. Effective sensor fusion to allow the pilot to make use of all this information, as well as information from onboard sensors.

3. An integrated EW system.

4. An AESA radar with a high level of reliability.

5. Training and doctrine necessary to make effective use of all this data and equipment. Plenty of flight hours for pilot flight training, too.

6. Powerful engines (ideally capable of supercruise), with a high mean time between overhaul and failures.

7. An airframe with low-observable characteristics.

8. A robust air-to-air refueling capability (equipment, readiness, training).

9. Sophisticated and reliable precision guided weaponry.

10. A robust software and hardware upgrade roadmap, to keep this plane effective in 5, 10, and 30 years.

11. Maintenance procedures in place to keep the plane operating with a high mission-capable rate. And of course equipment that has been designed with easy access for maintenance and easy access for electronic diagnostic tools, and ideally a sophisticated health-usage monitoring system (HUMS).

This list is not in any particular order of magnitude. And I’m sure I’ve missed quite a few other key items.

The J-20 offers one item from this list (#7). I’m not convinced that the PLAAF has any other items from this list, although China seems to be making some progress with #9.

It’s kind of fun to watch the world fixate on this one item (#7). Then again, I still enjoy air shows, too. Pugachev’s Cobra maneuver, for example. Drives the crowd wild. Relevance to modern combat? Zero.

As for the F-35, it certainly has its problems, especially regarding the price tag. But most, if not all, of the customers and partners are sophisticated enough to have a list that’s a lot more comprehensive than the one above. And I’m sure the appearance of item #7 as a prototype in PLAAF markings affects exactly none of their thinking.
 

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I read that article the other day and was immediately astonished at how flawed it is.

Firstly, we know that China has AWAACS, multiple variants in fact, as is continuing to develop the concept.

Suggesting the Chinese do no understand maintenance is to imply that they are stupid, which clearly they are not.

The J-20 has an upgrade path in the same way that the F-35 has an upgrade path, if money is provided it will be upgraded.

Most of the stuff on that list we have no hope of knowing in the near future.
 

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frank said:
Does it really make sense tho, to consider 5th gen a/c would be based on a 30+ year old demonstrator?
The Chinese combined the roles of a MiG-31 & Su-34 in a stealth airframe, the result- a kinda F-35 on steroids (though not F-22/T-50). It suites their military requirements i.e long-range/endurance A-A stand-off interceptor (hence 1.44 heritage) with formidable strike characteristics -it aint a dog-fighter, that may follow as the PLAAF feel the upgraded J-10/11 will serve as an effective complement at least in the medium term.

These roles will provide serious headaches for those this aircraft was designed in mind, namely Japan, Taiwan, Australia, India & USPACFLT.

The endless delays in India's MMRCA selection may yet prove a blessing in disguise, as the winner will have to contend with the 'J-20 factor'.
 

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it *should* be able to dogfight given that they chose such configuration:

*large deflecting surfaces with vortex generators*
*lateral stability from dorsal fins*

these reflect high maneuverability requirements under a well established config: canard-delta

given its length, it may mean a large volume for the weapons bay tailored for their long range arsenal

as for its speed, some of the research papers regarding the DSI will hold the clue. this may also be limited by the strength of the single piece canopy...
 

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Matej said:
I agree with the assumption that the decision to allow the aircraft to perform the taxi tests in front of the general public was largely meaned as the response to the Indo-Russian agreement. At least it makes sense.
Just to add that it is also very unlikely, that this was planned in the long term, because according to the latest information that I analyzed, the original date of the first flight was scheduled to the early 2nd quater of 2010.
 

JFC Fuller

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Matej said:
Matej said:
I agree with the assumption that the decision to allow the aircraft to perform the taxi tests in front of the general public was largely meaned as the response to the Indo-Russian agreement. At least it makes sense.
Just to add that it is also very unlikely, that this was planned in the long term, because according to the latest information that I analyzed, the original date of the first flight was scheduled to the early 2nd quater of 2010.
This has nothing to do with the Indo-Russian arrangement, it has to do with the current J-20 programme status, the aircraft was ready for taxi trials so it undertook them. Such conspiracy nonsense has no place here.
 

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Sukhoi T-50 was also ready for the taxi tests and did you see dozens of Russian citizens affixioned around the runway with the telelenses? Did you see the same when the early J-10 flights took place? Of course, the relation to the agreement is only the speculation, but what I am saying is that the reason, that we see so many photos now is that the China has a good reasons to ALLOW the leak of information in such a large scale. One of them can be that agreement. If they decide to make the runway tests in secrecy, they for sure have the better places for doing that than the single runway in the middle of the town.
 

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bobbymike said:
Teal Groups aviation expert Richard Aboulafia gives his F-35 v. J-20 "quickie" analysis (from Defensetech.org)

I would gauge a modern combat aircraft’s capabilities by looking at the following features:

1. Access to offboard space, ground, and air-based sensors, particularly a capable AEW/AWACS system with a well-trained crew and robust data links.

2. Effective sensor fusion to allow the pilot to make use of all this information, as well as information from onboard sensors.

3. An integrated EW system.

4. An AESA radar with a high level of reliability.

5. Training and doctrine necessary to make effective use of all this data and equipment. Plenty of flight hours for pilot flight training, too.

6. Powerful engines (ideally capable of supercruise), with a high mean time between overhaul and failures.

7. An airframe with low-observable characteristics.

8. A robust air-to-air refueling capability (equipment, readiness, training).

9. Sophisticated and reliable precision guided weaponry.

10. A robust software and hardware upgrade roadmap, to keep this plane effective in 5, 10, and 30 years.

11. Maintenance procedures in place to keep the plane operating with a high mission-capable rate. And of course equipment that has been designed with easy access for maintenance and easy access for electronic diagnostic tools, and ideally a sophisticated health-usage monitoring system (HUMS).

This list is not in any particular order of magnitude. And I’m sure I’ve missed quite a few other key items.

The J-20 offers one item from this list (#7). I’m not convinced that the PLAAF has any other items from this list, although China seems to be making some progress with #9.

It’s kind of fun to watch the world fixate on this one item (#7). Then again, I still enjoy air shows, too. Pugachev’s Cobra maneuver, for example. Drives the crowd wild. Relevance to modern combat? Zero.

As for the F-35, it certainly has its problems, especially regarding the price tag. But most, if not all, of the customers and partners are sophisticated enough to have a list that’s a lot more comprehensive than the one above. And I’m sure the appearance of item #7 as a prototype in PLAAF markings affects exactly none of their thinking.
The problem I have with analyses of this type is that they depend far too much on past performance. If someone had asked Aboulafia to expound on the same issue on December 21st he may well have been tempted to dispute China's ability to even come up with item #7. "The J-20 offers one item from this list (#7)." should really read "The J-20 *is known* to offer one item from this list (#7).". Fortunately, the worst case scenario is generally distinct from the most likely scenario, but it is often instructive to at least examine the latter.

IMHO it would be foolish to assume that China does not understand the concept of an aircraft as a weapons system and the importance of force multipliers. To suggest that they would develop the J-20 in a vacuum is absurd - how sophisticated their planning and concept of operations for this fighter really are is anybody's guess, but dismissing their efforts in this area out of hand could be a costly mistake.
 

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Hot damn! Some very nice CG posted on CDF...
http://www.china-defense.com/smf/index.php?topic=5373.msg153992#msg153992
 

JFC Fuller

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Matej said:
Sukhoi T-50 was also ready for the taxi tests and did you see dozens of Russian citizens affixioned around the runway with the telelenses? Did you see the same when the early J-10 flights took place? Of course, the relation to the agreement is only the speculation, but what I am saying is that the reason, that we see so many photos now is that the China has a good reasons to ALLOW the leak of information in such a large scale. One of them can be that agreement. If they decide to make the runway tests in secrecy, they for sure have the better places for doing that than the single runway in the middle of the town.
China allows the leak of everything, submarines, aircraft carriers, destroyers, tanks, missiles, etc etc etc. The controlled leak of information through supposedly independent Chinese observers is standard. Linking it to India is absurd and intellectually flawed.
 

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sealordlawrence said:
Matej said:
Sukhoi T-50 was also ready for the taxi tests and did you see dozens of Russian citizens affixioned around the runway with the telelenses? Did you see the same when the early J-10 flights took place? Of course, the relation to the agreement is only the speculation, but what I am saying is that the reason, that we see so many photos now is that the China has a good reasons to ALLOW the leak of information in such a large scale. One of them can be that agreement. If they decide to make the runway tests in secrecy, they for sure have the better places for doing that than the single runway in the middle of the town.
China allows the leak of everything, submarines, aircraft carriers, destroyers, tanks, missiles, etc etc etc. The controlled leak of information through supposedly independent Chinese observers is standard. Linking it to India is absurd and intellectually flawed.
You might be overstating the point ("absurd and intellectually flawed"). A large part of the funding that is making the PAK-FA feasible is a result of the India-China arms race and China is equally or more worried about India than the United States. The Chinese are generally very concerned about appearances and prestige (both internally and externally).

Americans care about their Jet Fighters as symbols of dominance, the Russians may care slightly more (even if they can afford much less) and the Chinese care more than the Russians! Everyone likes to have a presence.

Trident said:
The problem I have with analyses of this type is that they depend far too much on past performance. If someone had asked Aboulafia to expound on the same issue on December 21st he may well have been tempted to dispute China's ability to even come up with item #7. "The J-20 offers one item from this list (#7)." should really read "The J-20 *is known* to offer one item from this list (#7).". Fortunately, the worst case scenario is generally distinct from the most likely scenario, but it is often instructive to at least examine the latter.

IMHO it would be foolish to assume that China does not understand the concept of an aircraft as a weapons system and the importance of force multipliers. To suggest that they would develop the J-20 in a vacuum is absurd - how sophisticated their planning and concept of operations for this fighter really are is anybody's guess, but dismissing their efforts in this area out of hand could be a costly mistake.
The analysis is also potentially flawed because of the tactical assumptions it makes. There are a lot of factors that could be critical to smaller countries or land locked ones which are ignored. These things might lead to a very different list. For example:
- Poorer countries require fuel efficiency to have well trained pilots (eg. The massive drop in Mig-31 practice flights when fuel prices went up).
- Similarly, a low unit cost is important, as is the ability for poorly trained ground crew to keep systems going (often with cheaper or older components - regardless of the actual engine reliability).
- Short & rough field capability may be more important than inflight refuelling for conventional defensive operations (ie. a lot of small countries will lose their refuellers - if the have bought any - near the start of a war; however, having a dispersed airforce can allow operations to take place even after major airfields are hit).
- Maneuverability at low altitude may allow terrain masking and compensate for lacking kinetic performance and lacking sensors which are capable of acquiring a target at long ranges (and acquisition ranges, along with missile autonomy may be more important than we realise).

This analysis assumes a very American perspective that simply doesn't match the needs of a lot of smaller countries. However, it may actually be more applicable to China than anywhere else. The emphasis on reliability is good and sensor integration (especially between units) is still critically important.
 

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sealordlawrence, would you be so kind and watch your language. there are plenty other forums where you can use your idioms
 

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Avimimus - Mr. Aboulafia openly acknowledges the shortcomings of his "quickie" analysis and IMO was not trying to make some over arching statement befitting airpower for every country.

Also the reason his perspective might "appear" American influenced is that America has had more actual combat sorties since WWII (Korea, Vietnam, Kosovo, Gulf I & II, A-stan, etc.) then every other nation on earth combined. America has the most integrated, overwhelming tactical and strategic airpower overmatch over the past fifty years and has developed operational theory that has literally "written the airpower handbook".

Now is this some magical guarantor of future superiority, no of course not, but any airpower analysis will be heavily influenced by American thought.
 

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Bruno - you can attach up to 8 pics per post :)

Click (more attachments) on the post window.
 

overscan (PaulMM)

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Interesting variations on the wing shape in the various cgi pics so far. Hard to be certain without an in flight shot.
 

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Aboulafia does OK as an analyst sometimes.

However, having seen his work on commercial aviation, he tends to overrate US technology and accomplishments versus non-US technology, and root military requirements are not his bailiwick.
 

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The J-XX was not the first fighter was designed as DSI(or Chinese call it “Bump” inlet). Despite those X-35 and F-16DSI, only J-10B and JF-17 was fitted same DSI seemingly, not for detail but only lips. Exhausting all of so-called DSI pattern, we can put them in three categories by the shape of lips: one is X-35 alike, two is JF-17 used, and three is F-35 LightningⅡ. One against me may claim categorizing them by some way else, but due to the cause of the Bump on design, which we have known and presumed as only way, were forced moi insist my method until guys you point out various way to design this DSI.
When I discussed DSI with friends on ICQ or WLM, most them disagree that VG DSI has been used on J-XX also some Chinese bigoted the advantage of DSI due to single reason which is divertless. The funny is many Chinese well-know and pointed the principle of shock-wave-ride as the advantage here totally forgot object making from same principle could be and mostly are completely different thing and use in various place. I have to explain it is the disadvantage of DSI compare to CARET inlet cause the DSI necessarily to be VG inlet, then losing all of advantage from fantasy and return to be a normal inlet.
The inlet was never such important till aircraft being jet era because tremendous air flow needed by turbo and air compressor, but before sonic flight, we didn’t face any big problem on inlet design, now, we have two. The one is boundary layer, the other is shock wave.
The boundary layer is a low speed air flow stick on the surface of any part of aircraft, rubbing with high speed air flow upon them give to the aircraft not only drag but also heat. This is totally rubbish for flight. This is also why we can see many measures and devices used want to remove it. Traditional inlet was set dam-board to divide boundary layer from air flow which shall be led into inlet. The boundary layer on the surface of inner inlet will be absorbed by tiny bore, then flipped out of airframe. This is still an inactive way till the theory of wave-ride created.
Being the creation of wave-ride theory, many knew the sock-wave can be used as lift, few knew another awareness was the shock-wave could be used to blow the boundary layer, this was the very primeval trial to test on F-105’s inlet. Although this could be a sort of active way to blow boundary layer up, however, since the shock-wave leading by curve board, its swept angle changing cause nowhere should be directed, then it to be a pentant direction. Contemporaneously, inactive way to remove boundary layer was developed parallelly on F11. The forebody of inlet was raised like brae to accept the boundary layer stably into enormous bores that drilled on the surface beforehand. Like nowadays, the tiny-bores on ramp board, the bores are same function but the ramp surface are little bit different. Previous one this fixed, modern ramp-board are movable for swept angle of shock wave adjusting. The interesting problem here is, it is the very movement of swept angle of shock-wave not only influenced the effect of blow boundary layer up but also could be adjusted by ramp angle. No matter the area the shock wave directed are disparate, the ramp where create shockwave could be possibly known. If the shockwave is the nature bane to the boundary-layer, then the place the shockwave is born, where the boundary-layer disappear naturally.
So the problem must solving by creating infinite shockwave on the surface ahead of inlet. There are many trials but none perfect, you can see segment of ramp-board on MiG-29 used isentropic principle but still needs some tiny-bores drilled at the end of part. Therefore, the ramp should be a kind of shockwave alike, making no boundary-layer stand on for any moment. This is a logical source of “bump”. The “bump” are capable to blow boundary-layer because its profile is made due to the surface which can create shockwave, all of these walk around how to press the boundary layer out of the surface, none of business to creating lift, conversely the “bump” bring benefit to reducing drag meanwhile bring trouble to the air-flow for engine.
Someone here must be an expert who calculate how many airflow needed by jet engine during various speed with proper altitude. This is not the point we concerned so far, the point we caught here is must be different flow under different condition. Variable profile or angle or any other shape to suit various air-flow or intuitively say speed and altitude has never being successful on any aspect up to now. If the curve of DSI made is suitable to this, it has already been successful on MiG or early aircraft. Isentropic inlet was not a new study on aviation. Now we can see why there are three type of lip coordinate with “bump”.
Since we already explained the profile of “bump” is made not for lift but only boundary-layer, regardless what advanced principle it used by, so we can image it not concerned so many to air-flow. If the curvature of “bump” could create multi-shockwave for adjusting airflow into duct, it won’t be three types of lip present. We all knew that ramp surface will stimulate shockwave, if the shockwave is not keen enough to blow all of boundary layer, then that’s why we saw still amount of bores being on the bump of Thunder fighter. If the shockwave raised by “bump” is so strong that can be a conical cover the lip, to compress the engine pretty well. The cuspidal lips on F-35 showing its well covered and remain the wide route for boundary-layer aside, but according to subsonic needs wide section of air duct, the “bump” still is a problem. If the top of the “bump” being too wide, it will break the supersonic flow, if too narrow, then, engine lacking airflow during subsonic. Here is nothing to do with boundary-layer but cross-section for sonic flow.
Now we can see J-XX use VG DSI to changing cross section of air duct. The movable part must consist of a two-dimensional surface. This inner surface just like another “bump” inside, and adhering inner surface of lips, when the triangle part stretch out, the inner “bump” goes closer to the outside “bump”, making cross section narrowly to adapt supersonic flow, while subsonic flight is making, the triangle tongue draw back.
 

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