Chengdu J-20 5th Generation Aircraft News & Discussions

[Brainsucker]

O.k. ... another attempt - even if a bit OT !

But IMO it is not that difficult.

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The first J-11 picture use WS10 while the second picture use AL31?

 

[Deino]

The first J-11 picture use WS10 while the second picture use AL31?

Sorry, first image: Top = WS-10A - bottom = AL-31F ... second image: left = AL-31F - right WS-10A.

 

[Brainsucker]

Sorry, first image: Top = WS-10A - bottom = AL-31F ... second image: left = AL-31F - right WS-10A.

So AL31F has longer thruster than WS10?

 

[Beast]

So AL31F has longer thruster than WS10?

WS-10B has 140KN thrust.

 

[Brainsucker]

Even the painted nozzles look different.

Here are #2015 nozzles. Notice the dark lines between the silver indicating the gap between the nozzle petals.

#2016 nozzles are a solid silver.

Where have we seen this before? Right here.

Deino, if you look at this J-20 prototype, that thrusters are short, unlike the AL-31F thrusters. Maybe it's indeed WS-10. But maybe I can be wrong.

WS-10B has 140KN thrust.

No, I mean the physical thruster area at the engine. Not the thrust power. It is the area of the engine where the fire go out. WS-10 has shorter and bigger hole, while AL-31 is longer and can make a smaller hole. At least, that what I interpreted from the Deino's picture.

 

[Deino]

Deino, if you look at this J-20 prototype, that thrusters are short, unlike the AL-31F thrusters. Maybe it's indeed WS-10. But maybe I can be wrong.

NO - at least IMO - if You measure the individual parts in length, number of pedals and so on, esp. the inner structure like the flameholder 8and even more since the WS-10-typical inner ring is missing, it is simply a strangely coated AL-31FN.

No, I mean the physical thruster area at the engine. Not the thrust power. It is the area of the engine where the fire go out. WS-10 has shorter and bigger hole, while AL-31 is longer and can make a smaller hole. At least, that what I interpreted from the Deino's picture.

I don't think so, since both engines are interchangeable, the diameter must be the same ... so IMO it only seems so due to the shorter pedals.

 

[Brainsucker]

NO - at least IMO - if You measure the individual parts in length, number of pedals and so on, esp. the inner structure like the flameholder 8and even more since the WS-10-typical inner ring is missing, it is simply a strangely coated AL-31FN.

I don't think so, since both engines are interchangeable, the diameter must be the same ... so IMO it only seems so due to the shorter pedals.

Yeah, I mean the pedals. WS-10 has shorter pedal.

 

[BoQ77]

Yeah, I mean the pedals. WS-10 has shorter pedal.

petals ?

 

[j20blackdragon]

I'll continue to play devil's advocate with regard to the engines.

If the J-20 is using the AL-31FN, why are the nozzles black?

If the black color is simply a coating, why apply the silver coating over it?

If the black color is some sort of 'primer' or undercoat for the silver coating, why is the inside of the nozzles also black?

 

[Deino]

I'll continue to play devil's advocate with regard to the engines.

If the J-20 is using the AL-31FN, why are the nozzles black?

... simply doe to a new material being tested as a coating for the nozzle.

If the black color is simply a coating, why apply the silver coating over it?

... since it was a different coating, which is now reoplaced by that black coating.

If the black color is some sort of 'primer' or undercoat for the silver coating, why is the inside of the nozzles also black?

... since we have so far no clear images of this "new" nozzle from the latest birds ...

But in return I do not understand why some still have so high hopes that from a new colour alone they try to conclude this nozzle as proof for the WS-10 or -15 if everythingelse speaks against these engines ?

Deino

 

[j20blackdragon]

Another mystery surrounding the J-20's engines are the complete lack of new engine deals with Russia.

In 2011, China signed a contract for 123 AL-31FN Series 3 engines.

Reported by Bloomberg here:
China Signs $500 Million Russian Jet Engine Deal, Vedomosti Says - Bloomberg Business

As far as I know, this was the first and last deal for the AL-31FN Series 3. The J-10B started production in 2013 with the delivery of these engines. Early J-10C appear to be using these engines also.

But if the rumors are correct, and the J-20 is entering production in 2016, what engines are expected to be used? Are we expected to believe that the J-20 is going to share the limited number of AL-31FN Series 3 with the J-10B/C production line? That would be absolutely ridiculous.

So in my opinion, as long as Salut remains silent regarding any involvement in the J-20 program and Rosoboronexport does not announce any new engine deals with China, the engines for the J-20 are highly likely to be Chinese. J-20 production could not continue otherwise.

 

[Pinnacle]

I usually have so many queries in my mind about J-20 but today i'll stick with one, for the effective use of DAS and high-off-bore sight, you need to have HMD, which HMD is being used or is in plans to be used on J-20 and what are its specs?
@Deino @cirr @Chinese-Dragon

 

[BoQ77]

But if the rumors are correct, and the J-20 is entering production in 2016, what engines are expected to be used? Are we expected to believe that the J-20 is going to share the limited number of AL-31FN Series 3 with the J-10B/C production line? That would be absolutely ridiculous.

So in my opinion, as long as Salut remains silent regarding any involvement in the J-20 program and Rosoboronexport does not announce any new engine deals with China, the engines for the J-20 are highly likely to be Chinese. J-20 production could not continue otherwise.

Your argument based on the assume that:
- the rumors are correct
- no any secret small order for new modified engine. This could be translated that "China ordered Russia for a modified engine design ( it's reasonable ) with some target requirements. And Russia is applying some running changes to the design to meet the expectation of China side and limitation for export variant ( mostly study for trimming some features from their AL-41FS design) ". The design will be lower performance than their exported Su-35 engines.
- China reach the great advancement on engine design.

Even in the case 3. the small quantity is expected and need long testing time ( refer the time of flight test for each prototype), because even with demand for some dozens of J-20, we realized the bigger essential demand for replacing obsolete J-6, J-7, J-8 ... by 500-600+ J-10 still depend on Russian engines. If China could manufacture good engine for J-20, we assume that China must be able to make good engines for J-10 easily.

 

[cirr]

 

[Deino]

I'll continue to play devil's advocate with regard to the engines.

....]

I'm joining the game with another question:

Just compare this latest J-20 image in full reheat - and we only have few of them - with WS-10B and AL-31F in a similar position ... what engine / afterburner has more similarities ?