Chengdu J-20 5th Generation Aircraft News & Discussions

[Deino]

 

[Dil Pakistan]

Has anyone got a picture of J20 with canards not open...!!!!!!!!

 

[j20blackdragon]

I want to reiterate again that there is something strange about the J-20's engines. I have better pictures this time.

First, look at the AL-31FN.

Now we zoom in. The AL-31FN has a 'double layer' arrangement in the blue petal area. All Russian engines in the AL-31 family have this characteristic.

I highlight the top layer and bottom layer clearly in the picture below.

Now look at the J-20 engine. Do you see the same petal arrangement? I don't. The nozzles are open in the picture below.

Nozzles are closed in this picture.

I know the nozzles look very similar at a cursory glance. But look at the pictures closely and study the petal arrangement carefully and you will see the difference.

 

[Deino]

I want to reiterate again that there is something strange about the J-20's engines. I have better pictures this time.

First, look at the AL-31FN.
...
Now we zoom in. The AL-31FN has a 'double layer' arrangement in the blue petal area. All Russian engines in the AL-31 family have this characteristic.
....
I highlight the top layer and bottom layer clearly in the picture below.
....
Now look at the J-20 engine. Do you see the same petal arrangement? I don't. The nozzles are open in the picture below.
...


I know the nozzles look very similar at a cursory glance. But look at the pictures closely and study the petal arrangement carefully and you will see the difference.

NO they are not, and YES they have exactly the same double layer arrangement as on all AL-31-family members ... You only cannot see the second layer as clear as in the image above, since it is a bit more blurred, but again all details are the same. The only missing characteristic detail is that typical row of 2 screws, which bare hidden under that serrated outer skin. Therefore I really don't understand what You want to show ?? Do You really think a minor difference will proof a WS-1X-type of engine ??

Sorry to disappoint You again, but all images You delivers - and esp. as long as they are not as clear and close-up as the J-10B ones - are only proving more and more that we see the same type of engine.

 

[grey boy 2]

 

[SQ8]

That's funny! I thought even a man with poor eyesights would be able to tell these are two different engines by just look at the positions of the screws. Yet, Deino use them to show they are the same engine.

On the J-10 both rows of screws are located on the FIRST set of petals that CAN expand, but on J-20, there are no screws on the FIRST row of petals and no strange triangular dots. The one row of screws are on the SECOND set of the petals that don't expand.
View attachment 354170

You can have the same engine, but different exhaust petal arrangement. Take a look at the PW-100 on both the F-15 and F-16.

 

[Asoka]

You can have the same engine, but different exhaust petal arrangement. Take a look at the PW-100 on both the F-15 and F-16.

It is possible, but it does not mean it is probable or it is the truth.

 

[j20blackdragon]

I want to reiterate again that there is something strange about the J-20's engines. I have better pictures this time.

First, look at the AL-31FN.

Now we zoom in. The AL-31FN has a 'double layer' arrangement in the blue petal area. All Russian engines in the AL-31 family have this characteristic.

I highlight the top layer and bottom layer clearly in the picture below.

Now look at the J-20 engine. Do you see the same petal arrangement? I don't. The nozzles are open in the picture below.

Nozzles are closed in this picture.

I know the nozzles look very similar at a cursory glance. But look at the pictures closely and study the petal arrangement carefully and you will see the difference.

Notice the gaps and spacing between the petals in the AL-31FN illustration below.

Completely nonexistent in the J-20 nozzle.

 

[j20blackdragon]

I'm sorry, but where exactly is the top layer and bottom layer? The top layer should be HIGHER than the bottom layer, and the edges of the overlap should be visible. I see a single layer.

AL-31FN

 

[SQ8]

It is possible, but it does not mean it is probable or it is the truth.

It is extremely likely and is closer to the truth than any other claims. The current J-20 is underpowered for what its requirements are until the WS-15 arrives a few years later.

 

[Naif al Hilali]

It is extremely likely and is closer to the truth than any other claims. The current J-20 is underpowered for what its requirements are until the WS-15 arrives a few years later.

Bismillah irr Rahman ar Raheem

Five more years to get their metallurgic and manufacturing processes down?

I assume they have good mastery of FADEC (Full-Authority Digital Engine Control) by now?

What was the main issue with the Chinese engines' perennial problems with slow spool-up times (going from idle to afterburner)?

Thanks if you have any information.

Hifz u kum Allah

Bismillah ir Rahman ar Raheem

The F-16's Pratt & Whitney Engine Nozzle:

The P&W-engined F-15's nozzle petals kept falling off and were just removed altogether and a 2% drag penalty accepted (until the GE engines came around:

The F-16's GE engine nozzle petals:

Hifz u kum Allah

 

[Asoka]

From https://zh.wikipedia.org/wiki/涡扇-15
"渦扇15目前已知資料，僅確定該發動機研發計畫始於1990年代[1]；西方國家認為該發動機可能向俄羅斯進口Yak-141戰鬥機使用的R-79V-300相關資料，但該方面情資目前未有可信根據支持。渦扇15的首次試車成功目前有兩種說法，一種說法為中國網路所傳出為2005年4月、西方國家則推定為2006年[2]；在2009年12月，網路論壇中開始出現渦扇15的實機裝載測試，2011年，黎明厂实现该发动机验证机提前交付，在2012年之後進入長時期的測試狀態[3][4]。實際服役時程將會在2020年配備在殲20戰鬥機上[5]。

渦扇15的性能目前仍以臆測值為主，西方國家認為在2009年測試版本已經可達成後燃推力輸出160仟牛頓[6]，在2012年的測試可能已達成180仟牛頓（40,000磅）的輸出表現[7]，西方觀察家估計渦扇15的推重比具有1:9之能力[6]

除了在戰鬥機上使用的版本，目前還有一款稱為SF-A之研發計畫，該計畫在2009年公布[8][9]；SF-A將渦扇15提高旁通比、取消後燃器，作為C919客機與運20運輸機之動力來源。SF-A輸出動力約為13噸級，原定計畫將在2016年完成原型機[10]；除此之外，尚有代號SF-B之研發計畫，但該計畫細節目前不明。"

Let's review the timeline of the WS-15 development program.

1.) Early 1990's, WS-15 is initiated, possibly using the Yak-141's R-79V-300 engine as reference.

2.) On 2005, the core engine of WS-15 was tested.

3.) On 2006, the overall design of WS-15 was approved.

4.) On December of 2009, ground test of WS-15 began.

5.) On 2011, a prototype was provided for initial testing

6.) On 2012, long endurance test began.

7.) Mysterious unidentified engine spotted on J-20 version 2013.

8.) 2020 is the latest date to equip the production version of J-20 with WS-15.

Right now, it's late 2016. Looks like China is on target. It would have taken China 30 years to develop the WS-15 engine. The timeline is similar to US and Russia's effort to develop the same class of Turbofan engine

 

[dingyibvs]

The sound of J-20 is nothing like that of the Su-27, Su-30, J-11 family and J-10 which uses the AF-31 engine. That's why I am convinced J-20 is not using the AF-31. It's a very different engine. And I not sure China would use an improved version of WS-10 either on J-20. So its truly a mystery.

You can't compare the two's sound, they're very different airframes, and the airframe can change the sound of an engine quite a bit. It's like speakers, if you put the same 8-inch woofer in different enclosures, they can sound very different.

 

[grey boy 2]

HD pictures

 

[Asoka]

You can't compare the two's sound, they're very different airframes, and the airframe can change the sound of an engine quite a bit. It's like speakers, if you put the same 8-inch woofer in different enclosures, they can sound very different.

That doesn't sound like a convincing argument.

I am sorry that doesn't sound like a convincing argument.