Chengdu J-20 news and analysis Part III

coanda

ACCESS: Secret
Joined
Feb 3, 2009
Messages
303
Reaction score
289
This gives a excellent view of WS-10 exhaust and those blow in panels.

It seems clear to me the original shot on the J-20 has the inner petals in a non-divergent position. There seem to be darker patches on them corresponding to the blow in panels.
Louvres covering the blow in apertures appear to be aligned to let upstream flow in to the central duct.
 

coanda

ACCESS: Secret
Joined
Feb 3, 2009
Messages
303
Reaction score
289
You have to be careful as engine thrust line usually has an offset angle. So the thrust line may be several degrees down and also toed out from the centreline. Establishing the angle of the fuselage is complicated by local curvature, camera angle etc.

There may be something there but you need more rigorous analysis.
Looks to me like mild TVC of the outer nozzle assembly only. I could see how that is setup with pistons/linear actuators arranged around the outside of the engine. Post 828 shows a difference in pitch angle between the two nozzles. Strangely the watermark is exactly in the most annoying place if you wanted to compare the two nozzles. Post 840 view from below does not seem to show noticeable toe angle.
 
Last edited:

BLACK_MAMBA

ACCESS: Confidential
Joined
Jul 17, 2019
Messages
86
Reaction score
156
It's probably sluggish. I have no doubts that China would otherwise have demonstrated it doing aggressive aerobatics like they marvelously did with that J-10.
However the minimal wing, forward large canard and elongated fuselage with internal weapons bays could make it a proper ride when it comes to acceleration once a proper engine is ultimately fitted as compared to other similar designs.
Who says they want to demonstrate the full capabilities of the aircraft? When the Gripen entered service in SA those first few public displays where also rather mundane... While I also doubt the J-20 has the thrust it needs/will have once WS-15 comes online, I wouldn't conclude much about it's maneuvering capabilities based off it's Zhuhai performance. What we saw there could have been flown by a Mirage F1 and I guarantee the J-20 has a better T-W ratio and better turning capabilities with FBW than a Mirage... The Chinese are holding back - by how much we will have to wait and see.
 

Blitzo

ACCESS: Secret
Joined
Jun 9, 2011
Messages
419
Reaction score
119
It's probably sluggish. I have no doubts that China would otherwise have demonstrated it doing aggressive aerobatics like they marvelously did with that J-10.
However the minimal wing, forward large canard and elongated fuselage with internal weapons bays could make it a proper ride when it comes to acceleration once a proper engine is ultimately fitted as compared to other similar designs.

Uhh prior to Zhuhai 2018 that displayed the J-10B demonstrator with TVC, all J-10 aerial displays were very conservative as well.

The J-10B demonstration with TVC was very much the exception, and remains the only domestic fighter airframe that we know of currently flying with TVC.
If you have to compare J-20's flight demonstration with J-10s, it should be most accurately compared to all of the various J-10 aerial displays we've seen that were not the TVC equipped J-10B demonstrator.
 

Trident

ACCESS: Top Secret
Senior Member
Joined
May 8, 2006
Messages
1,274
Reaction score
767
Free floating implies to me a system that moves under pressure balance loads. Possibly under certain conditions the cooling air under the AB liner is significantly higher pressure than the central flow, and these mini petals are opening to prevent throttling this airflow into the gas path.

If the inner nozzle really opens to lie completely flush with the outer contour (the J79 seems to leave a sizable circumferential gap, and even the NK-25 should allow some leakage), your assessment could be correct.
 

latenlazy

I really should change my personal text
Joined
Jul 4, 2011
Messages
222
Reaction score
16
It's probably sluggish. I have no doubts that China would otherwise have demonstrated it doing aggressive aerobatics like they marvelously did with that J-10.
However the minimal wing, forward large canard and elongated fuselage with internal weapons bays could make it a proper ride when it comes to acceleration once a proper engine is ultimately fitted as compared to other similar designs.

Uhh prior to Zhuhai 2018 that displayed the J-10B demonstrator with TVC, all J-10 aerial displays were very conservative as well.

The J-10B demonstration with TVC was very much the exception, and remains the only domestic fighter airframe that we know of currently flying with TVC.
If you have to compare J-20's flight demonstration with J-10s, it should be most accurately compared to all of the various J-10 aerial displays we've seen that were not the TVC equipped J-10B demonstrator.
Alternatively, the example I like to go to is China’s flankers. We’ve seen Russian flankers do jaw dropping displays at air shows but we have never seen anything even close out of Chinese flankers in aerial displays, and yet these two birds are basically identical in their aerodynamic and kinematic characteristics.
 

latenlazy

I really should change my personal text
Joined
Jul 4, 2011
Messages
222
Reaction score
16
Since we now have official length and wingspan numbers for the J-20 we can calculate the J-20's actual reference wing area. To do this I basically divided the reference wing area in half into two congruent trapezoids (formed by the leading edge and trailing edge lines drawn all the way to the centerline of the fuselage), and used the trapezoid area formula ((a+b)/2)*h. For the total length of the aircraft in the picture I measured ~334 pixels. I measured the length of side a to be ~168 pixels, and side b to be ~24 pixels. Using 21.2m as the real length, side a = (168/334)*21.2 m = 10.66 m. Side b = (24/334)*21.2m = 1.52 m. The height h in this case is half the wingspan, which using the given 13.1m would make h = 6.55 m. ((10.66+1.52)/2)*6.55 = 39.89 m^2. Double that for the total wing area and you get 79.78 m^2. Obviously these measurements aren't perfect so attach some error bars to the calculation, but more or less the J-20 seems to be within ballpark of the F-22's wing area, if not slightly bigger.
 

Attachments

  • Screen Shot 2021-10-04 at 1.59.15 AM.png
    Screen Shot 2021-10-04 at 1.59.15 AM.png
    3.5 MB · Views: 88

Inst

ACCESS: Confidential
Joined
Oct 18, 2019
Messages
63
Reaction score
42
If you use the middle two aircraft, which show less longitudinal distortion, the figure is closer to 77.5 m^2 based on 21.3 and 13.01.

Enclosed is a larger satellite photo for Secret Projects.
 

Attachments

  • 1-jpg[1].png
    1-jpg[1].png
    3.6 MB · Views: 100

sferrin

ACCESS: USAP
Senior Member
Joined
Jun 3, 2011
Messages
14,614
Reaction score
3,539

bring_it_on

I really should change my personal text
Joined
Jul 4, 2013
Messages
2,586
Reaction score
872
The 500th F-35A for the USAF is included in the FY-22 budget request (22 NDAA isn't expected to change dramatically for the F-35A). Of these, about 300 have already been delivered. I think the lawmaker was trying to imply that PACAF needs to have as many 5th gen fighters as all of PLAAF? If so, he would be better served by pushing the USAF to completely overhaul its plans to transition existing units to F-35A's and delay fielding F-35A's in Europe by at least a decade.
 

In_A_Dream

ACCESS: Secret
Joined
Jun 3, 2019
Messages
328
Reaction score
202
We are years behind China's production capacity unfortunately. Congress is still too consumed with politics, or waiting for a trigger event, to drive a major shift in US Defense manufacturing right now.
 

siegecrossbow

I really should change my personal text
Joined
Mar 13, 2012
Messages
78
Reaction score
50

sferrin

ACCESS: USAP
Senior Member
Joined
Jun 3, 2011
Messages
14,614
Reaction score
3,539
The 500th F-35A for the USAF is included in the FY-22 budget request (22 NDAA isn't expected to change dramatically for the F-35A). Of these, about 300 have already been delivered. I think the lawmaker was trying to imply that PACAF needs to have as many 5th gen fighters as all of PLAAF? If so, he would be better served by pushing the USAF to completely overhaul its plans to transition existing units to F-35A's and delay fielding F-35A's in Europe by at least a decade.
500+ J-20s and J-31s on top of that.
 

bring_it_on

I really should change my personal text
Joined
Jul 4, 2013
Messages
2,586
Reaction score
872
On top of what and by when? I don’t think that even a prototype or the J-31 has flown ( besides the original demonstrators). They’ll always have more than PACAF but we’re still buying nearly 90 F-35s a year b/w the three users.
 

Blitzo

ACCESS: Secret
Joined
Jun 9, 2011
Messages
419
Reaction score
119
J-20 Nbr in service: possibly 150


They're citing SCMP, from an article that was roundly criticized for being ridiculous and an author with a track record for not being able to recognize a good source let alone interpreting what they're saying.

Don't believe everything one needs on the internet.


There are almost certainly not 150 J-20s in service, likely to be over 60 at present, maybe 70-80 tops.


Also, what??

"Some 15 J-20s flew in formation at Zhuhai, which took place in late September and early October, and observers reported an additional group of the aircraft parked on the runway."

15 J-20s in a formation?? What are they talking about...
 

latenlazy

I really should change my personal text
Joined
Jul 4, 2011
Messages
222
Reaction score
16
J-20 Nbr in service: possibly 150


They're citing SCMP, from an article that was roundly criticized for being ridiculous and an author with a track record for not being able to recognize a good source let alone interpreting what they're saying.

Don't believe everything one needs on the internet.


There are almost certainly not 150 J-20s in service, likely to be over 60 at present, maybe 70-80 tops.


Also, what??

"Some 15 J-20s flew in formation at Zhuhai, which took place in late September and early October, and observers reported an additional group of the aircraft parked on the runway."

15 J-20s in a formation?? What are they talking about...
They might have gotten the 100th anniversary of the CPC parade confused with Zhuhai lol.
 

Blitzo

ACCESS: Secret
Joined
Jun 9, 2011
Messages
419
Reaction score
119
J-20 Nbr in service: possibly 150


They're citing SCMP, from an article that was roundly criticized for being ridiculous and an author with a track record for not being able to recognize a good source let alone interpreting what they're saying.

Don't believe everything one needs on the internet.


There are almost certainly not 150 J-20s in service, likely to be over 60 at present, maybe 70-80 tops.


Also, what??

"Some 15 J-20s flew in formation at Zhuhai, which took place in late September and early October, and observers reported an additional group of the aircraft parked on the runway."

15 J-20s in a formation?? What are they talking about...
They might have gotten the 100th anniversary of the CPC parade confused with Zhuhai lol.

I think they just don't know how to recognize sources and don't know how to interpret them.
 

latenlazy

I really should change my personal text
Joined
Jul 4, 2011
Messages
222
Reaction score
16
J-20 Nbr in service: possibly 150


They're citing SCMP, from an article that was roundly criticized for being ridiculous and an author with a track record for not being able to recognize a good source let alone interpreting what they're saying.

Don't believe everything one needs on the internet.


There are almost certainly not 150 J-20s in service, likely to be over 60 at present, maybe 70-80 tops.


Also, what??

"Some 15 J-20s flew in formation at Zhuhai, which took place in late September and early October, and observers reported an additional group of the aircraft parked on the runway."

15 J-20s in a formation?? What are they talking about...
They might have gotten the 100th anniversary of the CPC parade confused with Zhuhai lol.

I think they just don't know how to recognize sources and don't know how to interpret them.
¯\_(ツ)_/¯ wouldn’t be the first time, probably not the last either.
 

sferrin

ACCESS: USAP
Senior Member
Joined
Jun 3, 2011
Messages
14,614
Reaction score
3,539
On top of what and by when? I don’t think that even a prototype or the J-31 has flown ( besides the original demonstrators). They’ll always have more than PACAF but we’re still buying nearly 90 F-35s a year b/w the three users.
Comparing the F-35 to the J-20 is the wrong comparison as they're not in the same class. I'm saying China will likely produce more than twice the number of J-20s as we did the F-22. Why wouldn't they? By when? Whether it's two years or twenty we're not building anymore F-22s so makes no difference. And I don't think we'll ever break triple into triple digits with NGAD.
 

Archibald

ACCESS: Above Top Secret
Senior Member
Joined
Jun 6, 2006
Messages
6,947
Reaction score
5,822
Depends whether the chinese economy doesn't slow dow or even collapse before then...
 

dark sidius

ACCESS: Secret
Joined
Aug 1, 2008
Messages
492
Reaction score
74
On top of what and by when? I don’t think that even a prototype or the J-31 has flown ( besides the original demonstrators). They’ll always have more than PACAF but we’re still buying nearly 90 F-35s a year b/w the three users.
Comparing the F-35 to the J-20 is the wrong comparison as they're not in the same class. I'm saying China will likely produce more than twice the number of J-20s as we did the F-22. Why wouldn't they? By when? Whether it's two years or twenty we're not building anymore F-22s so makes no difference. And I don't think we'll ever break triple into triple digits with NGAD.
You are right J-20 is not the F-35 class and we are realy not sure F-35 will dominate the J-20 in air combat, the F-22 fleet is to little, its time to NGAD to come instead USAF will lose the air dominance for sure and it will realy be a danger for everyone.
 

dark sidius

ACCESS: Secret
Joined
Aug 1, 2008
Messages
492
Reaction score
74
Depends whether the chinese economy doesn't slow dow or even collapse before then...
Don't count on it, in my opinion the F-35 program is a loud mistake , instead USAF had better idea to augment the F-22 fleet with upgraded F-22, the F-35 is a waste of dollars. Now USAF have just one option running very fast in direction of NGAD.
 
Last edited:

siegecrossbow

I really should change my personal text
Joined
Mar 13, 2012
Messages
78
Reaction score
50
Depends whether the chinese economy doesn't slow dow or even collapse before then...
Don't count on it, in my opinion the F-35 program is a loud mistake , instead USAF had better idea to augment the F-22 fleet with upgraded F-22, the F-35 is a waste of dollars. Now USAF have just one option running very fast in direction of NGAD.

Why are there hundreds of them manufactured every year then? People tend to underestimate the F-35. Compared with the Raptor, it has superior avionics and radar, EODAS, HOBS, possibly longer range and superior stealth. Also, did you know that they haven’t integrated AIM-120D with the Raptor yet? Aerodynamics isn’t everything you know.
 

Ainen

I really should change my personal text
Joined
Aug 25, 2011
Messages
68
Reaction score
39
we are realy not sure F-35 will dominate the J-20 in air combat
Setting the question as "whether we're not sure a 2010s strike fighter will dominate 2010s heavy air superiority fighter" is strange.
You're almost setting yourself up for a disappointment.
 

dark sidius

ACCESS: Secret
Joined
Aug 1, 2008
Messages
492
Reaction score
74
Sure but USAF is going to have a lot of strike fighter and little fleet of air superiority fighter it is time to return the sistuation , soon China will have hundred of air superiority fighters and the F-22 fleet is way too smal to counter it.
 

In_A_Dream

ACCESS: Secret
Joined
Jun 3, 2019
Messages
328
Reaction score
202
Depends whether the chinese economy doesn't slow dow or even collapse before then...

They've been heralding the collapse of China's economy for decades, China's ministry of propaganda even furthers this narrative to make people discount China.

You are right J-20 is not the F-35 class and we are realy not sure F-35 will dominate the J-20 in air combat, the F-22 fleet is to little, its time to NGAD to come instead USAF will lose the air dominance for sure and it will realy be a danger for everyone.

In a strict 1v1 engagement, I would imagine the F-35 could detect, launch, & jam before the J-20 would even know it's there.
 

totoro

ACCESS: Secret
Joined
Jan 11, 2011
Messages
466
Reaction score
227
The talk about Chinese 5th gen plane numbers compared to US ones should be subject to the reality of the present and near future.
Fact is - US is currently producing several times more 5th gen planes than China, each year.
Fact is - US has a head start in already produced 5th gen fighters, yielding a ten times bigger 5th gen fleet.

Here are some charts that show the difference in numbers.
Case 1 and Case 2.
usafplaaf case12.JPG
Case 1 assumes China will go to as many as 36 j20 produced per year. (of all possible variants)
It also assumes it will go to as many as 48 j31 produced for both their air force and navy.

Case 1 also assumes f-35 production will remain at current 90-ish airframes for all 3 US services and will slowly taper off when close to the 2400 airframes produced goal. Of course, that means it assumes there will be no cheap f-16 replacement design but that F-35 will soldier on and will be bought in full quantity.
It also assumes 24 USAF NGAD planes per year, with a long upkeep in production. Basically replacing F-22s and some F15s and perhaps even adding more fighter units to the USAF over the decades.
NGAD USN is also produced at up to 24 per year, which should be enough to replace the Superhornets, given that those superhornets will soldier on for quite a while, after a 10 000 flight hour airframe refurbishment.

In the end, even with such figures, for which some will say that they're unrealistically high for China - China will have barely more than half the 5th gen numbers of the US come 2045. A quarter of a century from now.
Keep in mind that at the height of their production, the 90+24+24 planes produced for the US - those figures will represent a 35% increase in annual fighter production over today.

Also, for China, current fighter production is at 90-ish airframes per year total, though most of it are 4th gen designs.
The chart does not mention 4th gen designs, which may still be in production up to a certain point.
84 5th gen planes produced per year is, of course, slightly less than 90ish airframes produced per year of today.

Case 2 has the US production figures remaining the same (as the point of the whole post is to explore upon Chinese figures, not the US ones) but has the Chinese production figures going up.
J-20 manages to reach 48 airframes per year, of all variants. (imagine two seaters, more strike oriented variants etc etc)
And the J-31 production manages to reach 64 airframes per year.
at 110 airframes produced per year, that case would see China produce 20% more airframes per year than today. And they'd likely all be 5th gen, unlike today, where a minority is 5th gen.

And yet, even with those numbers, which will be labeled as unrealistically high by some, by 2045 China manages to reach only 67% of the US numbers.

So then we explore cases 3 and 4, with super high Chinese production.
usafplaaf case34.JPG
US remains the same in the chart, while China goes to whopping 64 J20 fighters of all variants per year and 90 J31 fighters of all variants per year. That's 154 5th gen planes per year. Or more 5th gen planes produced per year than the US. At 154 planes per year, China is producing 70% more planes annually than today. And they're all 5th gen planes, at that.
And even so - by 2045 the total number of Chinese 5th gen planes is still several hundred fewer than the US fleet. The US would have some 20% more 5th gen planes altogether in 2045.

The last case is Case 4. The US remains the same but China ups its production even more. Here the j20 figures remain as they were in case 3, but j31 figures are lower per year, because a whole new single engine design is taking their place. Produced at a whopping 90 planes per year, on top of all other 5th gen planes. Case 4 has China produce whopping 218 fighter planes per year. While US remains at its high of 138.
And yet - come 2045, China barely outpaces US in total numbers.
Even with such super-production and such difference in annual production figures, China is ahead by only 2.5 percent.

Please note that all the Cases have the F-22 fleet fully retired and
not aggregated with the final US tally in 2045.

Bottom line - even if China started to increase its fighter production at a tremendous rate - and even if that produced NO response from the US - so for whatever reason US produced the same number of planes in all cases - it would still take a quarter of a century, and nearly 60% more planes produced than US annually at a certain point - to simply reach parity or very slightly go over it.

Disclaimers:
1. These charts and this post does not insinuate anything past the numbers.

2. Yes, not all planes are similarly capable. The post does not
equate quality of J20 with quality of NGAD or F-35.

3. Numbers are hardly the most important thing in an actual war. This post does not insinuate differently.

4. This post may show a production number for either side that you do or don't agree with. These are just 4 cases out of many possible cases. Some will see the Chinese production figures as unattainably high. Others will see US figures are too high. Others yet will see US figures as too low.

5. Certainly, this post does not even try to imagine what a US response in fighter production would be if China DID start producing so many fighters. The US response might be multifaceted, but even if part of it is done by increasing fighter production of its own- it's likely US own figures would go up at least to some degree. Which is why the later cases, namely 3 and 4, where China is going super high in production would likely be met with increased US production. So in fact, even the Chinese case 4 would be unlikely to ever result in total 2045 tally where Chinese 5th gen and 6th gen planes eclipse the US such planes in numbers.

6. Names of models in tables are just tentative. Of course it's possible that by 2040ish China will NOT be producing J20 anymore, for example, but will be producing its successor. Perhaps something akin to NGAD. These charts do not show that clearly but they simply assume the same number of planes in the J20 column as some next gen planes, despite the J20 designation of that column.

TL;DR: China is unlikely to reach US combat plane numbers (5th gen or otherwise) within our active lifetimes. (unless there are teenagers here on this board) Now, just how many planes is enough for what is a much broader topic - dependent on each side's allies, on tactical situation, where the fight is, etc etc. While China may project more of its power even with a smaller air fleet in battles close to China, the Pacific Ocean (let alone near the US mainland) is likely to remain US controlled within our lifetimes.
 
Last edited:

FighterJock

ACCESS: Top Secret
Joined
Oct 29, 2007
Messages
2,000
Reaction score
850
I cannot wait to see what the new twin seat trainer variant of the J-20 looks like, I certainly hope that they have not just crammed in the second cockpit at the expense of fuel.
 

Manuducati

ACCESS: Confidential
Joined
Nov 25, 2020
Messages
58
Reaction score
174
I cannot wait to see what the new twin seat trainer variant of the J-20 looks like, I certainly hope that they have not just crammed in the second cockpit at the expense of fuel.
Looking good in my humble opinion, if the artist renditions are legit.
 

Attachments

  • FB_IMG_1602943052128.jpg
    FB_IMG_1602943052128.jpg
    20.5 KB · Views: 3
  • FB_IMG_1602943057751.jpg
    FB_IMG_1602943057751.jpg
    52.4 KB · Views: 4

Blitzo

ACCESS: Secret
Joined
Jun 9, 2011
Messages
419
Reaction score
119
I cannot wait to see what the new twin seat trainer variant of the J-20 looks like, I certainly hope that they have not just crammed in the second cockpit at the expense of fuel.
Looking good in my humble opinion, if the artist renditions are legit.

Those are non official artistic renditions, and the second one depicts a more dramatic "strike" twin seater.

This image below is one that was featured for a brief second in an AVIC video last year which is probably the most likely appearance at this stage imo.


Also, I would be surprised if it operates as a trainer. If it operates in any form as a trainer, it would likely be for advanced tactics development.
A more plausible role, one floated by one of the more credible insiders over a year ago, is that of an enhanced battle management and UAV controller aircraft.


twin seat.jpeg
 

Similar threads

Top