J-20 5th Generation Fighter VII

KFX · Jul 13, 2020

Inst said:
Logically speaking, let us say the claim contains components A, B, and C. If component B is wrong, then the claim is wrong, which you have noted. But it doesn't imply that components A and C are necessarily wrong as well.

The claim that I'm paying attention to from Minnie Chan is that there's a J-20B which is intended to be a J-20A with TVC nozzles attached and integrated into the flight control system, and that the J-20B is going to be mass produced.

I'm treating this not as blatantly wrong, as other posters claim here, but as a plausible claim from a low-reliability source that needs further substantiation.

===

I also don't see that it can be assumed that the Chinese aren't running AL-31F engines on the J-20B, even though the WS-10B is considered ready. If you look at the rear design for the J-20, the J-20 has a significant problem in that its nozzle placement isn't optimal for TVC, not because the nozzles are adjacent, but because the nozzles are recessed by the rear ECM pylons.

The WS-10 engine, compared to the AL-31F, as can be seen on this CJDBY thread:

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is shallower and shorter than the AL-31F. This means that there needs to be substantial modification to move the nozzles further outward from the main body. Since the AL-31F engine, in contrast, is longer, there is less modification needed to move the nozzles outward.

===

In either case, it's a goddamn Minnie Chan claim. Plausible, yes, but needs further substantiation. Simply because it comes from her doesn't mean it's right or wrong, it just means it's unreliable and requires further evidence.

I'm with Inst on this. We need (a lot) more verification. Thrust vectoring, even in just two dimensions, would be of great benefit to the the J-20. The idea that the Chinese would use AL-31F for this, however, seems bizarre, as does entering "mass production" with a Russian engine, especially given that China appears to be making progress on the engine front, as evidenced by J-10B TVC. If nothing else, the fact that we've had a few pages of posts going back and forth about a dubious article highlights the dearth of credible information on the J-20 programme.

Figaro · Jul 13, 2020

KFX said:
I'm with Inst on this. We need (a lot) more verification. Thrust vectoring, even in just two dimensions, would be of great benefit to the the J-20. The idea that the Chinese would use AL-31F for this, however, seems bizarre, as does entering "mass production" with a Russian engine, especially given that China appears to be making progress on the engine front, as evidenced by J-10B TVC.

Dude, the premise of @Inst's argument is wrong because the SCMP article he cited is wrong. The J-20 "B" is not entering production currently with thrust vectoring AL-31s. We have many photos of production J-20s with WS-10X non-TVC engines. As for the TVC, the Chinese are doing three dimensional, not two dimensional thrust vectoring (check out the Zhuhai 2018 show) ... but this will system will only appear on the real J-20B alongside the WS-15.

KFX said:
If nothing else, the fact that we've had a few pages of posts going back and forth about a dubious article highlights the dearth of credible information on the J-20 programme.

All our credible information regarding the J-20 comes from either official sources (which are very rare) or via rumors from credible sources in Chinese military forums/social media. Of course there will be a dearth of credible information on the J-20 if you look on mainstream media (i.e. SCMP, National Interest, etc).

Inst · Jul 13, 2020

Figaro said:
Dude, the premise of @Inst's argument is wrong because the SCMP article he cited is wrong. The J-20 "B" is not entering production currently with thrust vectoring AL-31s. We have many photos of production J-20s with WS-10X non-TVC engines. As for the TVC, the Chinese are doing three dimensional, not two dimensional thrust vectoring (check out the Zhuhai 2018 show) ... but this will system will only appear on the J-20B alongside the WS-15.

Thing is, the AL-31F already has variants with functional TVC, whereas the Chinese have yet to debut a mass-production WS-10B with TVC nozzle. The J-10C tech demonstrator is there, of course, but it requires time to iron out the kinks and prove reliability.

The simplest and easiest way to get a J-20 with TVC up is just to buy an AL-31FP or AL-41-1S and configure the flight control system to support it. As you can see, the Russians are even more broke than before Ukraine with coronavirus having shut down their economy, so they're even more desperate and more amenable to transfer of technology deals.

And before you say that Russian engines preclude mass production, consider that the J-10 was on AL-31FN for many many years, and entered mass production with Russian engines. The Chinese already have AL-41-1S via the Su-35S engine.

So the claim that there exists a J-20B with TVC going into mass production is not implausible, but lacks substantial evidence due to Minnie Chan's standard of reporting.

That doesn't make it wrong, it just makes it unproven.

===

I just want to say, for the J-20 project, the worst possible news has already arrived. The WS-15, according to our leaks and the engine production schedule for a listed Chinese engine manufacturer, is apparently going to be very very late, and people are now trying to defend the WS-10-equipped J-20 as first-tier. So I don't see why using Russian engines for TVC might be seen as a sign of bad news, and the introduction of TVC on the J-20 with Russian engines could even be seen as good news, since the capability of the J-20 is now enhanced.

Once again, of course, this is unsubstantiated rumor courtesy Minnie Chan.

KFX · Jul 13, 2020

Figaro said:
Dude, the premise of @Inst's argument is wrong because the SCMP article he cited is wrong. The J-20 "B" is not entering production currently with thrust vectoring AL-31s. We have many photos of production J-20s with WS-10X non-TVC engines. As for the TVC, the Chinese are doing three dimensional, not two dimensional thrust vectoring (check out the Zhuhai 2018 show) ... but this will system will only appear on the J-20B alongside the WS-15.

All our credible information regarding the J-20 comes from either official sources (which are very rare) or via rumors from credible sources in Chinese military forums/social media. Of course there will be a dearth of credible information on the J-20 if you look on mainstream media (i.e. SCMP, National Interest, etc).

It's too soon for you, or anyone in this forum, to confidently state the focus of China's thrust vectoring efforts. These "official sources" you cite can be manipulated, as can these "credible sources" on Chinese social media. Dude: we're dealing with China.

Figaro · Jul 13, 2020

Inst said:
Logically speaking, let us say the claim contains components A, B, and C. If component B is wrong, then the claim is wrong, which you have noted. But it doesn't imply that components A and C are necessarily wrong as well.

The claim that I'm paying attention to from Minnie Chan is that there's a J-20B which is intended to be a J-20A with TVC nozzles attached and integrated into the flight control system, and that the J-20B is going to be mass produced.

I'm treating this not as blatantly wrong, as other posters claim here, but as a plausible claim from a low-reliability source that needs further substantiation.

===

I also don't see that it can be assumed that the Chinese aren't running AL-31F engines on the J-20B, even though the WS-10B is considered ready. If you look at the rear design for the J-20, the J-20 has a significant problem in that its nozzle placement isn't optimal for TVC, not because the nozzles are adjacent, but because the nozzles are recessed by the rear ECM pylons.

The WS-10 engine, compared to the AL-31F, as can be seen on this CJDBY thread:

Please, Log in or Register to view URLs content!

is shallower and shorter than the AL-31F. This means that there needs to be substantial modification to move the nozzles further outward from the main body. Since the AL-31F engine, in contrast, is longer, there is less modification needed to move the nozzles outward.

===

In either case, it's a goddamn Minnie Chan claim. Plausible, yes, but needs further substantiation. Simply because it comes from her doesn't mean it's right or wrong, it just means it's unreliable and requires further evidence.

This literally makes no sense at all. For the past year, we have been receiving pictures of J-20s in yellow primer with the WS-10X without thrust vectoring. Then all of a sudden, Minnie Chan goes on to rave about how J-20s with thrust vectoring AL-31s are going into mass production. Does this make any sense to you given the pictures we've been seeing? The designation is also completely wrong as well ... the J-20Bs should be referring to those with the WS-15s (which have the TVC ability). Here is a snippet from Pupu, who confirmed that the J-20B will have thrust vectoring on Weibo.

Figaro · Jul 13, 2020

KFX said:
It's too soon for you, or anyone in this forum, to confidently state the focus of China's thrust vectoring efforts. These "official sources" you cite can be manipulated, as can these "credible sources" on Chinese social media. Dude: we're dealing with China.

Of course no one here has 100% confidence until we have official or pictorial confirmation. But there is basically universal agreement that the J-20B will be fitted with a thrust vectoring WS-15 (most likely similar to the one we saw at Zhuhai). People often blame Chinese military developments for being "too secretive" when they themselves are too lazy to dig through the sources and rumors. It's not like China is censoring news/rumors of military development.

ougoah · Jul 13, 2020

Inst said:
Thing is, the AL-31F already has variants with functional TVC, whereas the Chinese have yet to debut a mass-production WS-10B with TVC nozzle. The J-10C tech demonstrator is there, of course, but it requires time to iron out the kinks and prove reliability.

The simplest and easiest way to get a J-20 with TVC up is just to buy an AL-31FP or AL-41-1S and configure the flight control system to support it. As you can see, the Russians are even more broke than before Ukraine with coronavirus having shut down their economy, so they're even more desperate and more amenable to transfer of technology deals.

And before you say that Russian engines preclude mass production, consider that the J-10 was on AL-31FN for many many years, and entered mass production with Russian engines. The Chinese already have AL-41-1S via the Su-35S engine.

So the claim that there exists a J-20B with TVC going into mass production is not implausible, but lacks substantial evidence due to Minnie Chan's standard of reporting.

That doesn't make it wrong, it just makes it unproven.

===

I just want to say, for the J-20 project, the worst possible news has already arrived. The WS-15, according to our leaks and the engine production schedule for a listed Chinese engine manufacturer, is apparently going to be very very late, and people are now trying to defend the WS-10-equipped J-20 as first-tier. So I don't see why using Russian engines for TVC might be seen as a sign of bad news, and the introduction of TVC on the J-20 with Russian engines could even be seen as good news, since the capability of the J-20 is now enhanced.

Once again, of course, this is unsubstantiated rumor courtesy Minnie Chan.

So you think it's possible the J-20B can be under mass production using an AL-41 TVC version similar to the one used on the Su-35 and Su-57 (before the IZD.30 is ready around 2025 as reported by Russians)? It's a possibility but really, really doubt this. About as likely as PLAAF buying another 100 Su-35s.

The J-20 has been using WS-10 engines since 2019. WS-10 TVC has been incorporated on a J-10 and probably tested on a J-20. TVC is NOT important at all especially for a stealth fighter. At most it allows for fewer and less dramatic control surface deflections which can sometimes help preserve VLO but most of the time these quick surface deflections show up for a split second and contrary to popular online myths, they don't spike RCS that much. It's so simple. Large surfaces may reflect radio energy back to the source and the entirety of a moving or non-moving surface can just happen to be in maximum reflection position at any arbitrary point in time. This applies to F-22, B-2, F-117 etc ... again surface deflections don't harm stealth that much simply because it's over very quickly and the spikes are still not going to be picked up significantly more frequently than the rest of the frame.

Unless the WS-10 TVC for some odd reason can't be fitted or used on the J-20 and the AL-41's can. But why would that be the case? They're nozzle length are not that dissimilar? Where is this arrangement issue you are talking about?

Figaro · Jul 13, 2020

ougoah said:
The J-20 has been using WS-10 engines since 2019. WS-10 TVC has been incorporated on a J-10 and probably tested on a J-20. TVC is NOT important at all especially for a stealth fighter.

Super-maneuverability was one of the key attributes of 5th generation fighters outlined by Dr. Song Wencong in his famous paper. The J-10 TVC was a test bed for the WS-15, which is confirmed to have TVC. Obviously, the Chinese do think TVC is very important for stealth aircraft, which explains why the J-20B will have this capability. With that being said, I don't think the Chinese are going to place the TVC system on the J-20s with Taihang engines with the WS-15 coming in the near future.

ougoah · Jul 13, 2020

Figaro said:
Super-maneuverability was one of the key attributes of 5th generation fighters outlined by Dr. Song Wencong in his famous paper. The J-10 TVC was a test bed for the WS-15, which is confirmed to have TVC. Obviously, the Chinese do think TVC is very important for stealth aircraft, which explains why the J-20B will have this capability.

I'll believe this infatuation with TVC on J-20 when I see it. When that happens, we'll know if it's WS-10 TVC or AL-41 TVC. I don't disagree that TVC is an eventual goal for most PLAAF platforms, particularly and realistically, future platforms only. It's going be prohibitively expensive to TVC all J-10s and J-11s. J-20s are stealth fighters. It just seems to me that the utility of TVC on a stealth fighter when it'll sacrifice some thrust, really isn't as high as integrating it on 4th gen fighters. Assuming TVC mostly enhances WVR capabilities with limited usefulness outside of this.

Since TVC is important as a piece of technology and where it could one day go, it's still important to make a start on it. But demontrators like the WS-10 TVC doesn't necessarily mean it must be applied eventually. You could consider them more as building blocks and learning tools. This doesn't mean WS-15 TVC won't be a thing especially if it represents yet another step in developing TVC tech and especially if it doesn't lose that much thrust.

Figaro · Jul 13, 2020

ougoah said:
I'll believe this infatuation with TVC on J-20 when I see it. When that happens, we'll know if it's WS-10 TVC or AL-41 TVC. I don't disagree that TVC is an eventual goal for most PLAAF platforms, particularly and realistically, future platforms only. It's going be prohibitively expensive to TVC all J-10s and J-11s. J-20s are stealth fighters. It just seems to me that the utility of TVC on a stealth fighter when it'll sacrifice some thrust, really isn't as high as integrating it on 4th gen fighters. Assuming TVC mostly enhances WVR capabilities with limited usefulness outside of this.

I really don't understand why it's so hard to believe the Chinese want thrust vectoring. Clearly a lot of development was placed into the J-10 TVC demonstrator system, not to mention the purchasing of 24 Su-35s to study the Russians' TVC system. These all indicate that the PLAAF is very serious about incorporating TVC into their future fighters. Pupu, Gongke101, and others have already confirmed that the WS-15 will feature TVC.

A blurb from Song Wencong's paper on this subject.

The future fighter, aside from satisfying low and mid-altitude maneuverability performance of modern 4th gen. fighters, must have the capability to supercruise and perform unconventional maneuvers such as poststall maneuvers. As a result, the aerodynamic configuration of the future fighter must not only satisfy the design constraints of RCS reduction but also lower supersonic drag, improve lift characteristics, and improve stability and controllability under high AOA conditions whilel accounting for trans-sonic lift to drag characteristics. The high number of design requirements provide new challenges to the aerodynamic layout. The design must employ new aerodynamic concepts and approaches, take necessary systematic and control measures, and compromise amongst the numerous design points in order to obtain the necessary design solution.

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J-20 5th Generation Fighter VII

KFX

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Figaro

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Inst

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KFX

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Figaro

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Figaro

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ougoah

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Figaro

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ougoah

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Figaro

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