J-20 5th Gen Fighter Thread V

[Air Force Brat]

No actually I think anyone who's seen enough doctored pictures should easily be able to tell this picture does not have any of the hallmarks of a doctored picture.

I don't know what you mean by "the two departing aircraft are very close" -- I assume you know what a two ship takeoff is like.
From the angle of the picture, the two J-20s look exactly like what we would expect for a two ship takeoff.

That digital image to promote the movie is NOT a Kodachrome 64 slide film image, it is digital, and it is likely a composite image, digitally remastered, and yes that would make it CGI.. the aircraft in your examples are flying in airshows, as evidenced by the fancy paint.

Military two ships are typically either left echelon or right echelon, and they tend to be much, much, looser, as it is much safer... the line abreast two ship is very difficult,,, the aircraft pictured are likely flying line abreast for the photo op value.

Most of the magazine photo's from the last Century were Kodachrome, as magazine editors did NOT want "doctored" images, just simple clean, well exposed slides, that where then processed in to "slicks", or glossy prints...

 

[Daniel707]

Pupu's recent post seems to imply that WS-10B Taihang Engine will be used to power the Chengdu J-20 in the near future.



Nb : The pic beside J-20 is Taihang mountains.

Hi:
The RCS of the J20 (by study of taiwanese NCSIST ESRD at 10 GHz)

Please, Log in or Register to view URLs content!

From Henri Kenhman

Please, Log in or Register to view URLs content!

And what 10GHz means?
Is that Good or bad one?

Can someone give enlighten to me for this one

 

[Deino]

Pupu's recent post seems to imply that WS-10B Taihang Engine will be used to power the Chengdu J-20 in the near future.

View attachment 41795

Nb : The pic beside J-20 is Taihang mountains.

Upps :what: ... does this mean from our list of three possible contenders for the current engine, suddenly two disappeared ??? :

Let me refrain the three option under discussions here:


1. an AL-31FN in the 200x-demonstrators, AL-31FN Series 3 for the 201x-prototypes and for the LRIP-birds a most likely an AL-31FM-2-based design (Deino-theory)

2. an WS-10-based design.

3. a prototype WS-15 from day one and now a +210kN serial WS-15 (Asoka-theory)


But if Pupu is correct and his post is slated to assume, that the WS-10B will be used to power the J-20 in the near future, it means so far the J-20 CANNOT be powered by a WS-10-version and if not even the WS-10 is mature, how could then be the WS-15 certified?

I would say if this is correct, options 2 & 3 just died a sudden death.
Or am I wrong ?

Deino

 

[manqiangrexue]

Pupu's recent post seems to imply that WS-10B Taihang Engine will be used to power the Chengdu J-20 in the near future.

View attachment 41795

Nb : The pic beside J-20 is Taihang mountains.




And what 10GHz means?
Is that Good or bad one?

Can someone give enlighten to me for this one

That model is wildly oversimplified. It can be "accurate" if it gave 2 things:
1. The model predicts RCS in relation to other parts of the plane, but has no definitive values.
2. It assumes that the entire plane was made of the same material/covering.

But if you gave both, then the simulation would be useless because 1. the material of the jet is unknown so you could not get definitive value based only on shape, and 2: different parts of the jet are made of different material, and basically none of that is publicly available. What's the stealth skin made of? Canopy? Radome cover? Engine petal covering? None of that is known and all will affect the actual stealth both in definitive figures and in relation to the other parts of the plane.

For the record, I'd prefer that Pupu not be correct because that would indicate to me some issues with the WS-15.

 

[Daniel707]

Upps :what: ... does this mean from our list of three possible contenders for the current engine, suddenly two disappeared ??? :

Let me refrain the three option under discussions here:


1. an AL-31FN in the 200x-demonstrators, AL-31FN Series 3 for the 201x-prototypes and for the LRIP-birds a most likely an AL-31FM-2-based design (Deino-theory)

2. an WS-10-based design.

3. a prototype WS-15 from day one and now a +210kN serial WS-15 (Asoka-theory)


But if Pupu is correct and his post is slated to assume, that the WS-10B will be used to power the J-20 in the near future, it means so far the J-20 CANNOT be powered by a WS-10-version and if not even the WS-10 is mature, how could then be the WS-15 certified?

I would say if this is correct, options 2 & 3 just died a sudden death.
Or am I wrong ?

Deino

But Pupu's post also don't give evidence to us that J-20 uses AL-31FM-2 Engine (Until this day, we still don't have any single evidence that China ever buy AL-31FM-2 from Russia)
We know that LRIP J-20 don't use AL-31 FN also.

But, like we know some Chinese media tell, their J-20 use Engine from their own factory.
So, is that possible if J-20 uses AL-31FM-2 Engine produced from their own Factory (just like WS-18 Engine)

That model is wildly oversimplified. It can be "accurate" if it gave 2 things:
1. The model predicts RCS in relation to other parts of the plane, but has no definitive values.
2. It assumes that the entire plane was made of the same material/covering.

But if you gave both, then the simulation would be useless because 1. the material of the jet is unknown so you could not get definitive value based only on shape, and 2: different parts of the jet are made of different material, and basically none of that is publicly available. What's the stealth skin made of? Canopy? Radome cover? Engine petal covering? None of that is known and all will affect the actual stealth both in definitive figures and in relation to the other parts of the plane.

For the record, I'd prefer that Pupu not be correct because that would indicate to me some issues with the WS-15.

Thanks for Information

 

[jobjed]

For the record, I'd prefer that Pupu not be correct because that would indicate to me some issues with the WS-15.

The WS-15 is predicted by the Liyang employee to be ready no sooner than 2022, about the same time the next-gen medium-thrust engine is ready, but Chinese engine programs usually get delayed so an estimate of 2025 is possible. From now til 2022, that's five years, and eight years if assuming 2025. That's a solid chunk of time for WS-10B to be mounted as interim engines.

If J-20 production remains steady at ~10 aircraft per year, that's 50-80 J-20s that require engines until WS-15 is ready. Employing WS-10B for these initial batches seems like a fine idea.

 

[Figaro]

The WS-15 is predicted by the Liyang employee to be ready no sooner than 2022, about the same time the next-gen medium-thrust engine is ready, but Chinese engine programs usually get delayed so an estimate of 2025 is possible. From now til 2022, that's five years, and eight years if assuming 2025. That's a solid chunk of time for WS-10B to be mounted as interim engines.

If J-20 production remains steady at ~10 aircraft per year, that's 50-80 J-20s that require engines until WS-15 is ready. Employing WS-10B for these initial batches seems like a fine idea.

I don't know about that. Many senior members like @tphuang believe his info is dubious because it contradicts everything we've heard thus far. But he does maintain a pretty large CJDBY fanboy base though ... so many ppl are gonna buy into his argument. There's another rumor that the WS-15 completed ground testing in late 2016 and is ready to be transferred on to the IL-76 testbed; hence, the China Daily article about the J-20 "receiving its domestic engine soon". I'm pretty sure that the J-20 will be first fitted with a WS-10x variant and then the 180kN WS-15.

 

[Quickie]

Hi:
The RCS of the J20 (by study of taiwanese NCSIST ESRD at 10 GHz)

Please, Log in or Register to view URLs content!

From Henri Kenhman

Please, Log in or Register to view URLs content!

One wonders why there's such a big variation between this chart and Carlo Kopp's J-20 RCS chart specifically on the frontal aspect (assuming both at 90 degree elevation).

On Kopp's Chart, a big chunk of the frontal aspect varies between -22.5 Dbsm and -40.0 Dbsm (@ 8 to 12 Ghz). The NCSIST chart varies between -7.0 Dbsm and -23.0 Dbsm without ever going down below -23.0 Dbsm (@10 Ghz) level at the same frontal aspect. This would be like the 2 charts coming from 2 different aircraft, which brings up the question of the feasibility of methodologies that was used since you can't have that much of a variation in RCS measurement for the same aircraft under the same condition.

 

[jobjed]

I don't know about that. Many senior members like @tphuang believe his info is dubious because it contradicts everything we've heard thus far. But he does maintain a pretty large CJDBY fanboy base though ... so many ppl are gonna buy into his argument. There's another rumor that the WS-15 completed ground testing in late 2016 and is ready to be transferred on to the IL-76 testbed; hence, the China Daily article about the J-20 "receiving its domestic engine soon". I'm pretty sure that the J-20 will be first fitted with a WS-10x variant and then the 180kN WS-15.

Tphuang hasn't posted in a long while so I can't get a reading on what his thoughts are. I wouldn't take the insider's words as gospel as he works in Liyang, not Liming, so he would only get second-hand or nth-ordinate-hand accounts of Liming's progress. He even says that himself; that of all the engine programs in China, he knows the least about the WS-15. Nonetheless, the secondary/tertiary sources that he has access to, while not perfect, are still more reliable than our conjecture.

The 2016 ground test rumour is ambiguous as to whether it's a test of just the engine core or a complete tech demonstrator. The

Please, Log in or Register to view URLs content!

doesn't contradict the insider's accounts at all. The article's individual-in-question said this: "the engine's development is proceeding well. We have also begun to design a next-generation aviation engine with a thrust-to-weight ratio that is much higher than that of current types." I'm interpreting that to mean there are two separate engines; one that will soon be mounted on J-20, and another next-generation engine, probably WS-15. So you're agreeing with me in that the J-20 will likely mount WS-10Bs before WS-15 is ready.

As an aside, the documentary from CCTV that said the J-20's engines were manufactured by Liming was ridiculed by literally every single experienced PLAAF watcher on Chinese BBS, including Huitong. There is no doubt that current J-20 engines are from the AL-31 family, even if the exact variant is unknown. And there is serious doubt that Liming is able to manufacture the AL-31 in its entirety because if they could, why buy from Russia?

 

[Hyperwarp]

Pupu's recent post seems to imply that WS-10B Taihang Engine will be used to power the Chengdu J-20 in the near future.

***

Sounds about right. So we could speculate as,

J-20A (WS-10?) - 2017
J-20B (WS-15, 3D-TVC, LOA-Nozzle) - 2025?

WS-10 series: 12000 kgf - 14000 kgf
WS-10IPE: 14700+ kgf (could as high as 15500 kgf)

Now the question is what's the thrust of the WS-10 for the J-20. If it is the WS-10IPE then the J-20 will have a lot of power when in full afterburner. Supercruise is a different matter altogether. We don't know the dry thrust of the WS-10 series.