Chengdu J-20 5th Generation Aircraft News & Discussions

[Ultima Thule]

I didn't say, China was used certain "plug&play" components to mated to the WS-15 core. I said, it used various mature and proven technologies "adapted" from WS-10 and AL-31FN. There is a difference here. China could manufacture all components of these two engines. So it is entire possible that Chinese Engineers could "adapt" their technologies to a new engine.

It was not a straight "plug & play". I don't know this is even possible. The different sizes and specifications of the components from three different engine, would be a big problem.

So I agree with you that such "plug & play" strategy is highly dubious. You got a point here, so your objection got some validity. But it was not a straight "plug & play". It can't be done, of course.

Between 2006 and 20011, there is enough time for China to "adapt" those proven technology to mate it with the new core.

You stole my word bro i am trying the same thing to @Deino sir well done brother

 

[j20blackdragon]

Even a Newsmax article dating back to October 2002 can confirm the delivery of engines for J-10:

At the end of 2001, China received a party of 54 AL-31FN engines, suggesting an initial production run of around 50 J-10 fighters.

http://www.newsmax.com/Pre-2008/Chinese-Airshow-Hit-With/2002/10/03/id/668123/

J-10 entered service in 2003.

J-20 entered service at the end of 2016.

Still no news of Russian engines. No news the AL-31FM2 progressed beyond bench testing in 2012. No news of any contract signed with China. These are the facts.

 

[帅的一匹]

Credit to the very advanced simulated altitude tests facility, WS15 will not fly with IL76 testbed but straightly go test on J20!!! WS15 is coming! Maybe still 3 to 5 years always from mass production! As an interim, Russian Al31F-M1 and WS10b will power J20 in LIRP.

There is no Al31F-M2, never.

The cockpit comparison between T50 and J20, then you will know why India is not willing to buy it in quantity:
https://view.inews.qq.com/a/20170315A07U5Q00

I'm very disappointed with the T50 cockpit, it didn't get rid off the old S27 design frame.

Thanks for your quick reply and more questions. Questions help me dig deeper and clarify my thoughts.

Why is China still making WS-10B/IPE engines to equip the J-20 and Flankers, if they got a more powerful WS-15?

Here is what I think:

1.) WS-15 is a new engine, which will still have its own issues and problems, years down the lines. WS-10 is already in service and matured.

2.) Being J-20's intended engine, equipping J-20 will be WS-15 highest priority. All other planes who want it, will have to wait after the orders for J-20 was satisfied.

3.) Because WS-15 is using new materials and new manufacturing process to boost it's Thrust. It will have production issue, to produces enough acceptable blades and other components, for a long time to come. Because the Compressor and Turbine, must be near perfect, the rejection rate for WS-10 blades are as high as 70%. That is for every 100 blades produced, only 30 will be accepted, or for every bladed installed, 3.33 blades will be rejected or wasted.

So, this production rate for WS-15 will be limited by this engine blade production rate. It will not be produced hundreds of copies per year, in the beginning.

And production rate of J-20, will be limited, by its engine production rate. The low production rate, (in the dozens, instead of hundreds, per year), of J-20, in coming years, will be a strong signal, that China has not totally mastered, the reliable production of WS-15.

4.) So, there will be no excessive WS-15 engine production capacity, for other airplanes, in the forceable future.

5.) Finally, because, WS-15, is a much more powerful engine, the airframes of J-10 and Flankers, must be redesigned and greatly strengthen, to handle this extra power, and the Digital Flight control system must be reprogrammed to incorporated this new engine.

And the planes, must be re-tested, all over again, like a brand new plane.

So, it is unlikely, that CAC will stop production of WS-10, and wait for WS-15 to equip the new J-10 and Flankers, coming down the production lines.

It will not be as simple as poop the new WS-15, into the new J-10 and Flankers, and tighten a few screws.

"It all makes no sense; Your thrust calculation makes no sense, the timeline does not fit for a regular engine esp. if other engines of lower thrust still have issues and most of all it's technically impossible."

So do your own very simple calculations, based on the method, I have shown, and see what numbers, you will come up with.

You don't have to post the result, if you think, it will embarrass you, and ruin your professional Journalist reputation. You can just do it, for your own benefit.

Look at the bright side.

If J-20, is using WS-15 ,and its thrust range is 180kN-210kN, not 160kN-180kn, as we previously believe, whoever report, this finding, first, on the mass medias outlets or website or newspaper or journal, will astonish the world.

He will be widely quoted and interviewed, for this military/aviation intelligence of the decade. And he will get a shot of world-wide-fame.

He will be laugh at, and disbelieved, at first, of course, but he will carefully present his simple, but solid calculations, to back him up.

I read a report that J-20 will be publicly display, on the ground in China, later this year. People will have a chance to take a close look at its engine.

So, potentially, journalists, have a six months window, to break this story, first, and astonish the world.

I agreed that +210kN upper range estimate is "iff", but the lower range of 180kN, is likely to be exceeded.

Because, to get a total thrust of 180kN, J-20 needs to have a flying weight of 22 tons (20 tons, empty weight + 2 tons of fuel, or some combinations like that)

It is incredible for J-20's empty weight, to be the same as F-22, despite its a much larger plane, with body length 3-4 meters longer.

And its also incredible, that any general will allow, his brand new 20 tons plane, to take off, with only 2 tons of fuel. I wouldn't allow a 10 tons plane, like F-16 to take off, with just 2 tons of fuel.

If it crashed, because of running out of fuel, its career ending, court martial, offense.

So, I stand with my estimate of 180kN - 210kN+ max. thrust range for WS-15.

It's likely to be higher than 210kN, because flying weight (26 tons) for this estimate, based the empty weight estimate of 22 tons and fuel of 4 tons, is still on the conservative side, IMO.

If he thrust go beyond 180KN, you need to increase the bypass rate, which means lame acceleration and maneuver like F35.

 

[Asoka]

Even a Newsmax article dating back to October 2002 can confirm the delivery of engines for J-10:

At the end of 2001, China received a party of 54 AL-31FN engines, suggesting an initial production run of around 50 J-10 fighters.

http://www.newsmax.com/Pre-2008/Chinese-Airshow-Hit-With/2002/10/03/id/668123/

J-10 entered service in 2003.

J-20 entered service at the end of 2016.

Still no news of Russian engines. No news the AL-31FM2 progressed beyond bench testing in 2012. No news of any contract signed with China. These are the facts.

"No news the AL-31FM2 progressed beyond bench testing in 2012. No news of any contract signed with China. These are the facts".

That's right. No news of AL-31FM2 delivery to China, whatsoever, neither before 2011, nor after.

Simply put, there is no case that military sales between Russia and China keep in secret. All were announced openly, and registered with the STOCKHOLM INTERNATIONAL PEACE RESEARCH INSTITUTE.

 

[j20blackdragon]

I want to ask some engine related smoke questions.

Look at the smoke produced by the FC-31. When have you seen the JF-17 (RD-93 engines) produce this much smoke? I've always noticed a little bit of smoke from the JF-17, but never this much. The older MiG-29s produced this much smoke, but when did Russia sell RD-33 to China?

Same question for J-20. When have you seen AL-31 (any variant) produce this much smoke? Can anyone show me Su-27/Su-34/J-10 producing this much smoke?

 

[j20blackdragon]

Another characteristic you don't see very often from Chinese Flankers and J-10: the J-20's yellow smoke.

"Yellow smoke is from high levels of nitrogen oxides in the exhaust; these are formed by high-temperature combustion. Lots of modern military engines will produce yellow smoke at high-dry/low-afterburner settings."

 

[Asoka]

You stole my word bro i am trying the same thing to @Deino sir well done brother

A big thanks for your appreciation, Bro!

 

[samsara]

Thanks for your quick reply and more questions. Questions help me dig deeper and clarify my thoughts.

Why is China still making WS-10B/IPE engines to equip the J-20 and Flankers, if they got a more powerful WS-15?

Here is what I think:

1.) WS-15 is a new engine, which will still have its own issues and problems, years down the lines. WS-10 is already in service and matured.

2.) Being J-20's intended engine, equipping J-20 will be WS-15 highest priority. All other planes who want it, will have to wait after the orders for J-20 was satisfied.

3.) Because WS-15 is using new materials and new manufacturing process to boost it's Thrust. It will have production issue, to produces enough acceptable blades and other components, for a long time to come. Because the Compressor and Turbine, must be near perfect, the rejection rate for WS-10 blades are as high as 70%. That is for every 100 blades produced, only 30 will be accepted, or for every bladed installed, 3.33 blades will be rejected or wasted.

So, this production rate for WS-15 will be limited by this engine blade production rate. It will not be produced hundreds of copies per year, in the beginning.

And production rate of J-20, will be limited, by its engine production rate. The low production rate, (in the dozens, instead of hundreds, per year), of J-20, in coming years, will be a strong signal, that China has not totally mastered, the reliable production of WS-15.

4.) So, there will be no excessive WS-15 engine production capacity, for other airplanes, in the forceable future.

5.) Finally, because, WS-15, is a much more powerful engine, the airframes of J-10 and Flankers, must be redesigned and greatly strengthen, to handle this extra power, and the Digital Flight control system must be reprogrammed to incorporated this new engine.

And the planes, must be re-tested, all over again, like a brand new plane.

So, it is unlikely, that CAC will stop production of WS-10, and wait for WS-15 to equip the new J-10 and Flankers, coming down the production lines.

It will not be as simple as poop the new WS-15, into the new J-10 and Flankers, and tighten a few screws.

"It all makes no sense; Your thrust calculation makes no sense, the timeline does not fit for a regular engine esp. if other engines of lower thrust still have issues and most of all it's technically impossible."

So do your own very simple calculations, based on the method, I have shown, and see what numbers, you will come up with.

You don't have to post the result, if you think, it will embarrass you, and ruin your professional Journalist reputation. You can just do it, for your own benefit.

Look at the bright side.

If J-20, is using WS-15 ,and its thrust range is 180kN-210kN, not 160kN-180kn, as we previously believe, whoever report, this finding, first, on the mass medias outlets or website or newspaper or journal, will astonish the world.

He will be widely quoted and interviewed, for this military/aviation intelligence of the decade. And he will get a shot of world-wide-fame.

He will be laugh at, and disbelieved, at first, of course, but he will carefully present his simple, but solid calculations, to back him up.

I read a report that J-20 will be publicly display, on the ground in China, later this year. People will have a chance to take a close look at its engine.

So, potentially, journalists, have a six months window, to break this story, first, and astonish the world.

I agreed that +210kN upper range estimate is "iff", but the lower range of 180kN, is likely to be exceeded.

Because, to get a total thrust of 180kN, J-20 needs to have a flying weight of 22 tons (20 tons, empty weight + 2 tons of fuel, or some combinations like that)

It is incredible for J-20's empty weight, to be the same as F-22, despite its a much larger plane, with body length 3-4 meters longer.

And its also incredible, that any general will allow, his brand new 20 tons plane, to take off, with only 2 tons of fuel. I wouldn't allow a 10 tons plane, like F-16 to take off, with just 2 tons of fuel.

If it crashed, because of running out of fuel, its career ending, court martial, offense.

So, I stand with my estimate of 180kN - 210kN+ max. thrust range for WS-15.

It's likely to be higher than 210kN, because flying weight (26 tons) for this estimate, based the empty weight estimate of 22 tons and fuel of 4 tons, is still on the conservative side, IMO.

Thank you every one, in particular @Asok for the good, informative and civilized exchanges of thoughts, I am learning by reading in this aspect.

Btw SCMP reported that China "may" hold a massive parade to celebrate the 90th Anniversary of the People's Liberation Army on August 1st, 2017.
Who knows what will China display at such grand event, only time may reveal with certainty.

 

[jkroo]

Very well arguments here. There are three facts here.
1. J20's target engine is Ws15.
2. What engines are used on current J20 is still unknown. No official confirmation yet. So everything is guess.
3. Time will tell us the fact, pls be patient.

 

[j20blackdragon]

Another characteristic you don't see very often from Chinese Flankers and J-10: the J-20's yellow smoke.

"Yellow smoke is from high levels of nitrogen oxides in the exhaust; these are formed by high-temperature combustion. Lots of modern military engines will produce yellow smoke at high-dry/low-afterburner settings."

A couple more pictures.

T-50 with yellow smoke.

Tu-160 with yellow smoke.

 

[j20blackdragon]

5.) Finally, because, WS-15, is a much more powerful engine, the airframes of J-10 and Flankers, must be redesigned and greatly strengthen, to handle this extra power, and the Digital Flight control system must be reprogrammed to incorporated this new engine.

And the planes, must be re-tested, all over again, like a brand new plane.

So, it is unlikely, that CAC will stop production of WS-10, and wait for WS-15 to equip the new J-10 and Flankers, coming down the production lines.

It will not be as simple as poop the new WS-15, into the new J-10 and Flankers, and tighten a few screws.

An aircraft engine is like a tailored suit for a man. The engine is custom built for the airframe and vice versa.

When the J-10's indigenous engine suffered serious difficulties in the mid 90s and had to be replaced by the Russian AL-31FN, the fuselage and engine intake were forced to be redesigned. The J-10 fuselage had to accommodate the heavier Russian AL-31FN engine, which also required a larger intake as it needed X percent more airflow.

Another example, the F135 is much larger than the F100/F110 engines. It is also larger in diameter than the F119. The airflow requirements for the F135 are much larger too.

Similarly, since the WS-15 is likely to be larger, heavier and needs more airflow to operate than the AL-31, the aircraft would need to have its intakes fundamentally redesigned. Internal bulkheads would need to be redesigned in the airframe midsection to accommodate the increased diameter of the larger engine. The airframe may need to be lengthened. Other components in the engine bay like actuators, fuel control, harnesses, tubing, gearbox, FADEC would need to be redesigned. Total weight of the aircraft would increase. Theses would not be cheap modifications. The entire aircraft would need to be retested and re-certified. Therefore, any theoretical upgrade from AL-31 to WS-15 would not be a simple "plug & play" either. Ideally, you either design an aircraft for AL-31 or WS-15. You don't do both. If you do both, you would almost be building a new aircraft.

When General He Weirong made the prediction in 2009 that a 5th generation fighter would enter service in "about eight to ten years," he was right on the money. You can't possibly make a prediction like that if you don't even know what engines you will use for your aircraft. The AL-31FM2 was still in bench testing in 2012. And yet General He Weirong made his amazing prediction in 2009. The J-20 flew in 2011. Something to think about.

 

[Asoka]

An aircraft engine is like a tailored suit for a man. The engine is custom built for the airframe and vice versa.

When the J-10's indigenous engine suffered serious difficulties in the mid 90s and had to be replaced by the Russian AL-31FN, the fuselage and engine intake were forced to be redesigned. The J-10 fuselage had to accommodate the heavier Russian AL-31FN engine, which also required a larger intake as it needed X percent more airflow.

Another example, the F135 is much larger than the F100/F110 engines. It is also larger in diameter than the F119. The airflow requirements for the F135 are much larger too.

Similarly, since the WS-15 is likely to be larger, heavier and needs more airflow to operate than the AL-31, the aircraft would need to have its intakes fundamentally redesigned. Internal bulkheads would need to be redesigned in the airframe midsection to accommodate the increased diameter of the larger engine. The airframe may need to be lengthened. Other components in the engine bay like actuators, fuel control, harnesses, tubing, gearbox, FADEC would need to be redesigned. Total weight of the aircraft would increase. Theses would not be cheap modifications. The entire aircraft would need to be retested and re-certified. Therefore, any theoretical upgrade from AL-31 to WS-15 would not be a simple "plug & play" either. Ideally, you either design an aircraft for AL-31 or WS-15. You don't do both. If you do both, you would almost be building a new aircraft.

When General He Weirong made the prediction in 2009 that a 5th generation fighter would enter service in "about eight to ten years," he was right on the money. You can't possibly make a prediction like that if you don't even know what engines you will use for your aircraft. The AL-31FM2 was still in bench testing in 2012. And yet General He Weirong made his amazing prediction in 2009. The J-20 flew in 2011. Something to think about.

"Ideally, you either design an aircraft for AL-31 or WS-15. You don't do both. If you do both, you would almost be building a new aircraft."

That's right. You can't design an aircraft with one engine, then loose a few screws, and poop in a different engine, a few years, with a entirely different design, specifications, weight, and power.

If you want to do, you need to start all over again, like a new aircraft, with all the design and testing process.

That' why I have a hard time, believing this nonsense, that J-20 is using either WS-10b or AL-31FN-M2 for the time being, waiting for WS-15 to get its act together. And after WS-15 is ready, simply just pop it in, and here you go.

"When General He Weirong made the prediction in 2009 that a 5th generation fighter would enter service in "about eight to ten years," he was right on the money. You can't possibly make a prediction like that if you don't even know what engines you will use for your aircraft. The AL-31FM2 was still in bench testing in 2012. And yet General He Weirong made his amazing prediction in 2009. The J-20 flew in 2011. Something to think about."

Yes, absolutely, correct.

Everything about the J-20 project went like clockwork, like a fine Swiss Timepiece. There was absolutely, no reports, no rumors, no hints, that any parts of the project encountered any serious difficulties or delays.

None whatsoever.

The preparations for the project was superb; execution, flawless; and the result, astonishing.

 

[UKBengali]

@Asok & @j20blackdragon

You can swap to WS-15 if it was on purpose designed with the same spacial dimensions as the one that it would be replacing. There is no logical reason the WS-15 cannot be externally an exact replica of either the AL-3L or WS-10X engine.

 

[Asoka]

@Asok & @j20blackdragon

You can swap to WS-15 if it was on purpose designed with the same spacial dimensions as the one that it would be replacing. There is no logical reason the WS-15 cannot be externally an exact replica of either the AL-3L or WS-10X engine.

"You can swap to WS-15 if it was on purpose designed with the same spacial dimensions as the one that it would be replacing. There is no logical reason the WS-15 cannot be externally an exact replica of either the AL-3L or WS-10X engine."

Name an instance, in the world history of modern aircraft development, that was successfully done, as you just have said, that an new engine and new aircraft was "as on purpose designed, with the same spacial dimensions", to replace "externally an exact replica" of an older, much less powerful engine.

Otherwise, the Mod. will level, the charge of, groundless speculation, at you.

Even, that's possible and desirable, it still won't explain, why a 130kN-140kn engine, like WS-10b or AL-31FN could lift, a plane weighting +20 tons plus fuel, in a sustained vertical climb, without the use of AB, in front of thousands of international spectators.

I got a feeling, that this crucial point, still don't mean anything to you, and to many other readers.

 

[52051]

According to a very trustful military insider, Pupu, J-20A will soon to be equpipped with WS-10B engine, with a thrust of 142kn.

This is consistent with the senior fellower of China academy of engineering's comments on how China will soon fit J-20 with home-made engines during the recent congress meeting.