Chengdu J-20 5th Generation Aircraft News & Discussions

[Tiqiu]

The very fact that we are here at PDF says all; the so-called fanboys and professionals are all sharing one commonality. We are pot and kettle.

On topic which engine J20 uses, I am very surprised since the debut of J20 at Zhuhai show, not many western professionals/experts cared on commenting the performance of the J20s and its engine. Normally those people alike would seize any opportunity to belittle Chinese achievements. Why tight- lipped this time?

I am not professional, nor do i pretend to be one.But isn't it a more professional way to judge which engine J20 uses by its flight performance in med-air rather than the appearance of the engine nozzle? Wrong claims can be made on fighter jets" rate of climb or thrust/weight ratio on paper, but the jet cant lie while flying in mid air. For those who don't agree, then at least you need to provide HD images showing every aspects of the nozzle of various type of engines in question to begin with.

I have spent some time to compare the video footages of J20's flight in mid with those of Su27s in order to make my own conclusion whether both jet are using the same or similar Russian engine that some professionals here want me to believe. During the J20 debut flight on Zhuhai Airshow, J20 performed vertical climb at low altitude without acceleration speed and no AFTERBURNER. Some spectator even suggested the speed was actually decelerating.But when I watched Su27 doing the same type of climb maneuver on footage, they all used afterburner, be it after taking-off or flying in mid air. Su27's empty weight is 16380 kg, around 3t lighter than J20, if they all use the AL31F/FN with 75KN dry thrust, how comes the heavier J20 can do the climbing without afterburner that Su27 can't?

Thus I think it is quite credible that J20 uses FWS10B, not a early model of FWS15s, but a 3.5 generation engine derived from J10A and part of FWS15 technology , which has 100 KN (dry)/155 KN(afterburner) thrust.

no afterburner when J20 doing vertical climb at 0:06, 0:52, 1:26 and 2:11

afterburner for Su27 doing the similar maneuver at 0:25 and 1:36

 

[Ultima Thule]

But there are people saying that it's not even ws-10x that's on the j-20s

Yes may be it uses WS-10X or AL-31FN3 so confusing ,but i am answering to @Asok that he was assuming that J-20 uses WS-15 from its first prototype 2001

 

[Beast]

The very fact that we are here at PDF says all; the so-called fanboys and professionals are all sharing one commonality. We are pot and kettle.

On topic which engine J20 uses, I am very surprised since the debut of J20 at Zhuhai show, not many western professionals/experts cared on commenting the performance of the J20s and its engine. Normally those people alike would seize any opportunity to belittle Chinese achievements. Why tight- lipped this time?

I am not professional, nor do i pretend to be one.But isn't it a more professional way to judge which engine J20 uses by its flight performance in med-air rather than the appearance of the engine nozzle? Wrong claims can be made on fighter jets" rate of climb or thrust/weight ratio on paper, but the jet cant lie while flying in mid air. For those who don't agree, then at least you need to provide HD images showing every aspects of the nozzle of various type of engines in question to begin with.

I have spent some time to compare the video footages of J20's flight in mid with those of Su27s in order to make my own conclusion whether both jet are using the same or similar Russian engine that some professionals here want me to believe. During the J20 debut flight on Zhuhai Airshow, J20 performed vertical climb at low altitude without acceleration speed and no AFTERBURNER. Some spectator even suggested the speed was actually decelerating.But when I watched Su27 doing the same type of climb maneuver on footage, they all used afterburner, be it after taking-off or flying in mid air. Su27's empty weight is 16380 kg, around 3t lighter than J20, if they all use the AL31F/FN with 75KN dry thrust, how comes the heavier J20 can do the climbing without afterburner that Su27 can't?

Thus I think it is quite credible that J20 uses FWS10B, not a early model of FWS15s, but a 3.5 generation engine derived from J10A and part of FWS15 technology , which has 100 KN (dry)/155 KN(afterburner) thrust.

no afterburner when J20 doing vertical climb at 0:06, 0:52, 1:26 and 2:11

afterburner for Su27 doing the similar maneuver at 0:25 and 1:36

Good observation! I suspect one of the requirement for PLAAF for J-20 to enter service is to have high dry thrust to ensure minimal usage of afterburner to reduce IR signature.

Remember this interview by Yang wei, chief designer of J-20 during Zhuhai 2016

He talk about the movement by J-20 is outstanding as demonstrated by J-20. He also claimed J-20 demonstrated , something not visible to others. So what does this sentence means? If he is talking about radar, its not possible. Those flight move is not possible to reveal the capabilities of its AESA. Not to mention stealthiness unless we have radar install there. Even with radar the ling berg lens will hide J-20 real stealthiness.

The only thing conclude can be the flight demonstrated something outstanding yet its hinting all this is possible due to a powerful engine that enable all this. It cannot be AL-31F engine.

 

[Tiqiu]

Good observation! I suspect one of the requirement for PLAAF for J-20 to enter service is to have high dry thrust to ensure minimal usage of afterburner to reduce IR signature.

Remember this interview by Yang wei, chief designer of J-20 during Zhuhai 2016

He talk about the movement by J-20 is outstanding as demonstrated by J-20. He also claimed J-20 demonstrated , something not visible to others. So what does this sentence means? If he is talking about radar, its not possible. Those flight move is not possible to reveal the capabilities of its AESA. Not to mention stealthiness unless we have radar install there. Even with radar the ling berg lens will hide J-20 real stealthiness.

The only thing conclude can be the flight demonstrated something outstanding yet its hinting all this is possible due to a powerful engine that enable all this. It cannot be AL-31F engine.

Exactly. This short but informative flying of J20 at a international show for the first time was meant to officially demonstrate some capabilities for the professionals of the world by China's authorities. For fanboys those images/footages leaked by the tree top party already do the job. The mere observation at close vicinity by those pilots of the British Red Arrow and the Russian Knights&Swifts aerobatic flight team would suffice for making sound and palpable conclusion about the engine. The Pak Army' s pilots were also there, who even uploaded the J20 flight video to youtube. If they were still using the under-powered Russian engine, the western commentators wouldn't be sitting still and keep their mouth shut, and certainly not so especially after the claims made by the Chinese professionals,chief engineer and even Air chief himself.

 

[Asoka]

The very fact that we are here at PDF says all; the so-called fanboys and professionals are all sharing one commonality. We are pot and kettle.

On topic which engine J20 uses, I am very surprised since the debut of J20 at Zhuhai show, not many western professionals/experts cared on commenting the performance of the J20s and its engine. Normally those people alike would seize any opportunity to belittle Chinese achievements. Why tight- lipped this time?

I am not professional, nor do i pretend to be one.But isn't it a more professional way to judge which engine J20 uses by its flight performance in med-air rather than the appearance of the engine nozzle? Wrong claims can be made on fighter jets" rate of climb or thrust/weight ratio on paper, but the jet cant lie while flying in mid air. For those who don't agree, then at least you need to provide HD images showing every aspects of the nozzle of various type of engines in question to begin with.

I have spent some time to compare the video footages of J20's flight in mid with those of Su27s in order to make my own conclusion whether both jet are using the same or similar Russian engine that some professionals here want me to believe. During the J20 debut flight on Zhuhai Airshow, J20 performed vertical climb at low altitude without acceleration speed and no AFTERBURNER. Some spectator even suggested the speed was actually decelerating.But when I watched Su27 doing the same type of climb maneuver on footage, they all used afterburner, be it after taking-off or flying in mid air. Su27's empty weight is 16380 kg, around 3t lighter than J20, if they all use the AL31F/FN with 75KN dry thrust, how comes the heavier J20 can do the climbing without afterburner that Su27 can't?

Thus I think it is quite credible that J20 uses FWS10B, not a early model of FWS15s, but a 3.5 generation engine derived from J10A and part of FWS15 technology , which has 100 KN (dry)/155 KN(afterburner) thrust.

no afterburner when J20 doing vertical climb at 0:06, 0:52, 1:26 and 2:11

afterburner for Su27 doing the similar maneuver at 0:25 and 1:36

Good observation. J-20 did not use afterburner for the whole performance, yet it's flight characteric is at least equal even better that the Flanker which used afterburner.

In my opinion, J-20 is unlikely using WS-10B or AL-31FN because WS-10B has 8 flaming link, AL-31-FN has 11, while J-20 has 8 flaming links as shown in the following pictures.

The bottom picture is the WS-10B with 8 flaming links in it afterburner.

Starting at 1:55, this TV show video claims at least one J-20 has equipped WS-15.

This video was first shown in 2013. It claims WS-15 has made major breakthroughs and paved the way for mass production. And the reason why WS-15's development is proceeding smoothly is because China purchased the design blueprint of the Russian Yak-141's engine and VTOL technology, the R-179-300, which has a maximum thrust of somewhere between 196 and 206 kN and a Thrust to Weight Ration of 11-12. Unreal! Amazing!

• 
  We know the Yak-141 engine was for sale because the American purchased the VTOL technology and used it on the F-35.

http://www.leteckemotory.cz/motory/r-79/index.php?en

 

[Deino]

Good observation. J-20 did not use afterburner for the whole performance, yet it's flight characteric is at least equal even better that the Flanker which used afterburner.

In my opinion, J-20 is unlikely using WS-10B or AL-31FN because WS-10B has 8 flaming link, AL-31-FN has 11, while J-20 has 8 flaming links as shown in the following pictures.

View attachment 356983

@Asok,

Your assumption is wrong, since Your image on the bottom shows clearly not a WS-15 but anything else. This image was posted even prior to the J-20's (2001) maiden flight in January and then rumoured to be a WS-10G ... (what would bit by the number of links), but a WS-15 is impossible.

Even more all images showing a J-20 in afterburner we know - and You posted most of them Yourself for comparison - all show the typical 11 links, not 8.

As such it seems Your are a bit flip-flopping the images, arguments only to prove what long has been a fact.

Anyway... time will tell.

Deino

 

[Asoka]

While, I am not absolutely certain the bottom two pictures are authentic. But it seems to be J-20 and its engine. It has 10 flaming links, not 11 as of the AL-31FN of the top right picture. The inside of the WS-15 is very similar to AL-31FN, but very different to WS-10B. In fact, honestly, I don't know any engine has 10 flaming rinks. I had look at a lot picture of inside the engine nozzles.

AL-31FN has three rinks that are evenly spaced, while WS-15's middle rink is much closer to the inner rink than to the outer rink.

"Even more all images showing a J-20 in afterburner we know"
Those images don't show the inside of the nozzle, with the engine NOT running to get a clear picture, so they are inconclusive.

While, I can see people may have a hard time believing WS-15 is already mature, stable and ready for mass production, but I just can't see anyone would have a hard time accepting WS-15 may have been installed on J-20 for testing, a while back.

Aircraft engine takes a long time to mature, and there is no better way to find out the potential problems than test it on an aircraft, after extensive ground testing, of course.

If WS-15's core engine is based on the Yak-141's r-179-300 engine, it may have the potential to reach 196-206kN as the Russians have claimed. This is absolutely astonishing.

I urge everyone to read this page.

http://www.leteckemotory.cz/motory/r-79/index.php?en

The leaked maximal thrust of WS-15 is 180kN. This is very high already compared to F-22's 160kN, but lower than's F-35's 190kN. However, F-35 has only one engine and is already overweight. Big Mistake!

If WS-15 does able to develop 206kN like the R-79-300 and go even higher in future models, it will bust anybody's behind, no problemo. China already developed a Titanium alloy that could withstand 2200K high temperature, which is crucial for this class of engine. So the road is open for this kind of new development.

This is so shocking. If the Americans has known this, they would certainly keep the production of F-22 going instead of stop at 187 units. They had always hoped the Chinese Engine Technology is not as good. True, the Americans had developed the F-22's P&W F119 engine and F-35 P&W F135, decades ago. But it is still shocking to see someone has caught up so quickly. Not so long ago, China had a great deal of troubles developing the WS-10.

Perhaps, this is why China has keep the development of WS-15 so secretive. Aircraft engine technology used to be our major weakness, now, it's suddenly our Trump card.

 

[Ultima Thule]

While, I am not absolutely certain the bottom two pictures are authentic. But it seems to be J-20 and its engine. It has 10 flaming links, not 11 as of the AL-31FN of the top right picture. The inside of the WS-15 is very similar to AL-31FN, but very different to WS-10B. In fact, honestly, I don't know any engine has 10 flaming rinks. I had look at a lot picture of inside the engine nozzles.

AL-31FN has three rinks that are evenly spaced, while WS-15's middle rink is much closer to the inner rink than to the outer rink.

View attachment 356993

"Even more all images showing a J-20 in afterburner we know"
Those images don't show the inside of the nozzle, with the engine NOT running to get a clear picture, so they are inconclusive.

While, I can see people may have a hard time believing WS-15 is already mature, stable and ready for mass production, but I just can't see anyone would have a hard time accepting WS-15 may have been installed on J-20 for testing, a while back.

Aircraft engine takes a long time to mature, and there is no better way to find out the potential problems than test it on an aircraft, after extensive ground testing, of course.

If WS-15's core engine is based on the Yak-141's r-179-300 engine, it may have the potential to reach 196-206kN as the Russians have claimed. This is absolutely astonishing.

I urge everyone to read this page.

http://www.leteckemotory.cz/motory/r-79/index.php?en

their is no confirmed images of WS-15 on net but in your assumptions

What is the prove that lower images is WS-15?

 

[Deino]

Simply, this image was posted well before the J-20's maiden flight ... IMO it is a mock-up only, nothing more. So to compare the number of detail in the inner flameholder as a fact but ignore all images we have showing a J-20 in afterburner is pure blindness only since it does not fit Your desire.

Again ... the WS-15 will show up some day and I'm sure we will be certain if it appears in the same way we can differ a WS-10 from an AL-31FN. There's really no need to create such fakes of a WS-10 mated with an AL-nozzle.

Deino

 

[Asoka]

Simply, this image was posted well before the J-20's maiden flight ... IMO it is a mock-up only, nothing more. So to compare the number of detail in the inner flameholder as a fact but ignore all images we have showing a J-20 in afterburner is pure blindness only since it does not fit Your desire.

Again ... the WS-15 will show up some day and I'm sure we will be certain if it appears in the same way we can differ a WS-10 from an AL-31FN. There's really no need to create such fakes of a WS-10 mated with an AL-nozzle.

Deino

"Simply, this image was posted well before the J-20's maiden flight ... "
I don't know this true. Hope you can provide a link to verify. The earliest post I could find with this picture is the link by our member Tiqiu on Jan 28, 2016. There was the same post and on the same day:
on http://site.6park.com/military/index.php?app=forum&act=threadview&tid=14602087

Remember, the "maiden" flight of Jan. 11, 2011 was accompanied with absolutely no fanfare, no flowers for the pilot, no jubilant celebration on the ground. It was flown very casually. It was a non even for the manufacture. In fact many people has speculated that there was two J-20 with the same version number of 2001, but the nozzle colors was different. The other one has long flown before this one.

"There's really no need to create such fakes of a WS-10 mated with an AL-nozzle."
One casual look at the "fake" picture, we can tell the inside of WS-10 (8 flaming links) is completely different than the WS-15 (10 flaming links) and AL-31 (11 flaming links).

IMO, J-20 is going into LRIP equipped with WS-15 and it has TVC nozzles.

 

[Deino]

"Simply, this image was posted well before the J-20's maiden flight ... "
I don't know this true. Hope you can provide a link to verify. The earliest post I could find with this picture is the link by our member Tiqiu on Jan 28, 2016. There was the same post and on the same day:
on http://site.6park.com/military/index.php?app=forum&act=threadview&tid=14602087

I have both images - even in the original colour version - dated 15. June 2011 and 5. September 2011. As such I need to correct myself - SORRY - it was not before, but anyway soon after the maiden flight. But both images are strange ... isn't it strange that a girl is standing in front of a super-secret new engine, a photographer can take an image of it and post it in a forum ?? How likely is this?

Here from my PC:

Remember, the "maiden" flight of Jan. 11, 2011 was accompanied with absolutely no fanfare, no flowers for the pilot, no jubilant celebration on the ground. It was flown very casually. It was a non even for the manufacture. In fact many people has speculated that there was two J-20 with the same version number of 2001, but the nozzle colors was different. The other one has long flown before this one.

But why should this be a hint for a WS-15 ?? The maiden flight itself was not much official even if there was indeed a celebration afterwards, we know images from the celebration and banquet showing the pilot, the design team and even its official PLAAF-project number was mentioned. I really did never expect the mentioning of the engine type., since this was not even mentioned on the J-10's maiden flight too.

"There's really no need to create such fakes of a WS-10 mated with an AL-nozzle."
One casual look at the "fake" picture, we can tell the inside of WS-10 (8 flaming links) is completely different than the WS-15 (10 flaming links) and AL-31 (11 flaming links).

Yes it is different, but at what we are looking at???
Again !!! WE have no image of the real WS-15 since by all reliable accounts this engine is only available in a test-specimen since last year's summer. So to be sure the WS-15 has 10 links is IMO a bit far fetched ??

All we can say it is something that looks like the J-20's engine, it appeared well within the early test-phase and has be seen with suspicious, due to that girl ??
There's no proof that this IS a WS-15 ... and IMO by all accounts it is more than unlikely.

Deino

 

[Asoka]

I have both images - even in the original colour version - dated 15. June 2011 and 5. September 2011. As such I need to correct myself - SORRY - it was not before, but anyway soon after the maiden flight. But both images are strange ... isn't it strange that a girl is standing in front of a super-secret new engine, a photographer can take an image of it and post it in a forum ?? How likely is this?

Here from my PC:
View attachment 357097



But why should this be a hint for a WS-15 ?? The maiden flight itself was not much official even if there was indeed a celebration afterwards, we know images from the celebration and banquet showing the pilot, the design team and even its official PLAAF-project number was mentioned. I really did never expect the mentioning of the engine type., since this was not even mentioned on the J-10's maiden flight too.

Yes it is different, but at what we are looking at???
Again !!! WE have no image of the real WS-15 since by all reliable accounts this engine is only available in a test-specimen since last year's summer. So to be sure the WS-15 has 10 links is IMO a bit far fetched ??

All we can say it is something that looks like the J-20's engine, it appeared well within the early test-phase and has be seen with suspicious, due to that girl ??
There's no proof that this IS a WS-15 ... and IMO by all accounts it is more than unlikely.

Deino

Thanks for your images. That's a great help. Now I know where it was first appeared. http://www.fyjs.cn/ or

"So to be sure the WS-15 has 10 links is IMO a bit far fetched ??"
This simply helps rule out that engine is WS-10 or AL-31FN.

We have three choices for J-20's engine. WS-10B, AL-31FN. The WS-10B is not much more powerful than AL-31FN. As we have seen on the China Airshow, the J-20 can do the entire flight, including vertical climbings, without the use of afterburner, whereas, the Flanker used afterburner for its entire flight. This kind of power demonstration is hard to fake. Pretty firm evidence, IMO.

That left just the WS-15 as the only choice left thats fits the bill.

As for those diehard doubters, a wiseman said: "It is not hard to wake up those who are willing to be awake, but it is damn near impossible to wake up those who are pretending to be sleep or unwilling to wake up, when the Sun has risen."

 

[Deino]

You are welcome !

 

[Asoka]

You are welcome !

I have learned that we are here to play armchair detectives to entertain each other. No need to be too serious and offensive. Thanks Deino!

 

[Tiqiu]

I have learned that we are here to play armchair detectives to entertain each other. No need to be too serious and offensive. Thanks Deino!

Agree
Classified info is classified for a reason. So we can all speculate here,no one,but time is entitled to give verdict.
By law of physics, I know those two J-20 jets in the debut demo flight at the Zhuhai air show must not be powered by any AL-31F.