Test pilot sees China's J-20 to get 2D thrust vectoring nozzles，surpassing the F-22

[xizhimen]

Test pilot sees China's J-20 to get 2D thrust vectoring nozzles，surpassing the F-22
By Liu Xuanzun
Published: Apr 19, 2021 10:43 PM

The pilot who first flew the J-20 believes that China's most advanced stealth fighter jet will be upgraded with 2D thrust vectoring nozzles for its engines, according to a recent news report.

This means the warplane will receive enhanced maneuverability and stealth capability and surpass its US counterpart, the F-22, a Chinese military expert said on Monday.

The J-20 is expected to be equipped with engines with 2D thrust vectoring nozzles, said Li Gang, the pilot of the J-20's first flight, when asked about his expectations on the future development of the J-20's thrust vector control capability in a recent interview with Hong Kong-based Phoenix TV aired on Monday.

J-20s in service with the People's Liberation Army (PLA) Air Force currently all use circular nozzles with no thrust vector control capability, analysts said.

Thrust vector control will provide extra maneuverability and 2D nozzles can enhance stealth capabilities of the J-20, Fu Qianshao, a Chinese military aviation expert, told the Global Times on Monday.

With the flight performance of the J-10B thrust vector control demonstrator at the Airshow China 2018 in Zhuhai, South China's Guangdong Province, China displayed its capability to develop and apply 3D thrust vectoring technology on fighter jets.

Explaining the differences between 2D and 3D thrust vectoring, Fu said that 2D nozzles are rectangular and 3D nozzles are circular, meaning that 2D nozzles have better radar and infrared stealth capabilities than the 3D nozzles.

The F-22 stealth fighter jet of the US Air Force uses 2D thrust vectoring, analysts noted.

3D nozzles are often believed to be capable of providing more thrust angles than 2D nozzles, as F-22's 2D nozzles can only move vertically, but this is a common misunderstanding, Fu said, noting that 2D nozzles can also move horizontally to provide horizontal thrust when so designed, but this design could add development costs.

In the Phoenix TV report, Li also said that he expects the J-20's thrust vectoring nozzles to move only vertically like the F-22, but Fu said that he hopes the J-20's future nozzles will be able to move horizontally, which will make the PLA fighter jet surpass its US counterpart in this aspect.

It has been long expected that the J-20 will eventually receive thrust vectoring-capable engines.

When asked about when the J-20 can get thrust vectoring-capable engines at a press conference of Airshow China 2018, shortly after the J-10B thrust vector control demonstrator made its flight performance, Yang Wei, chief designer of the J-20, replied, "You asked about when, but how do you know it hasn't?" This statement is widely interpreted by military observers that the J-20's developers have been testing thrust vector control on the aircraft for a long time.

2021 marks the 10th year of the J-20's maiden flight, and the stealth fighter jet is seeing many new developments, including domestically made engines, removal of Luneburg lens in exercises, and possible development of a twin-seat variation, according to media reports.

Test pilot sees China's J-20 to get 2D thrust vectoring nozzles - Global Times

www.globaltimes.cn

 

[Beast]

Why 2D? Maybe more stealthy?

 

[HostileInsurgent]

3D? USA uses 2D in F22 because its nozzles are rectangular in shape to mask IR signature, Russians and even NATO engine makers have demonstrated 3D thrust vectoring.

 

[Deino]

As you know I cannot read Chinese, but here is a kind summary from "taxiya" at the SDF:

Brief translation:
ifeng: In your opinion, what kind of TVC should J-20 have?
Li Gang: 2D TVC works like this. (demonstrating with his hands).

My observation:

1. It is ifeng reporter, not CCTV reporter.
2. The video belongs to "Xiao Yang Shi Pin", a youtube like video platform operated by CCTV. It does not belong to any CCTV official channel. Therefor this reporter is more like a "Self Media".
3. Apperantly Li Gang's words were cut out from a full sentence. So he might not even talk about J-20's TVC. He might not even talk to the ifeng reporter.
4. Even he was interviewed by this ifeng reporter, he did not say anything about J-20, not shown by the video at least.

My conclusion is, there is no value in this video. From the way the video is cut, I highly suspect that the ifeng reporter is deliberately fabricating 2D TVC using Li Gang's position. A very common practice by "Self Media".

 

[Cookie Monster]

3D? USA uses 2D in F22 because its nozzles are rectangular in shape to mask IR signature, Russians and even NATO engine makers have demonstrated 3D thrust vectoring.

China could also do 3D...using two of those TVC version of WS10 they demonstrated on J10...or by implementing that TVC on whatever other engine they might use on J20. What I've heard is that 2D TVC is supposedly more stealthy...this is not my area of expertise...so I don't know if this is true or not.

 

[IblinI]

China could also do 3D...using two of those TVC version of WS10 they demonstrated on J10...or by implementing that TVC on whatever other engine they might use on J20. What I've heard is that 2D TVC is supposedly more stealthy...this is not my area of expertise...so I don't know if this is true or not.

both options are on the table, it depends on the PLA's choice.

 

[Cookie Monster]

both options are on the table, it depends on the PLA's choice.

going on a tangent while we are talking J20 engines here...I always wondered why the designers of J20 chose to have that groove on the underbelly of the jet towards the back section(it's obviously bcuz of the engines)...
...wouldn't it be better if they had it flat? ...the more uneven a surface...the more likelihood of radar waves returning back to the source? They can just flatten it...and use that space(where that groove is) for more fuel or more avionics or something. Flat underbelly...and 2D TVC at the end of it

 

[Beast]

going on a tangent while we are talking J20 engines here...I always wondered why the designers of J20 chose to have that groove on the underbelly of the jet towards the back section(it's obviously bcuz of the engines)...
...wouldn't it be better if they had it flat? ...the more uneven a surface...the more likelihood of radar waves returning back to the source? They can just flatten it...and use that space(where that groove is) for more fuel or more avionics or something.

I think that will increase unnecessary weight and restrict airflow towards the nozzle.

 

[Cookie Monster]

I think that will increase unnecessary weight and restrict airflow towards the nozzle.

It would be a minor increase in weight...that will be acceptable bcuz of advantages gained...like a stealthier airframe(less uneveness to reflect back radar waves) and whatever avionics or fuel that space is used for.

As for airflow towards the nozzle...I assume u mean for mixing cool air with the hot air coming out of the nozzles...to dissipate the heat(relatively quickly) in order to reduce the IR signature. That can be solved by diverting some of the air taken in by the engine directly towards the exhaust(mixing it with hot air...before it exits)...see this illustration of a 3 stream engine concept.

 

[FuturePAF]

Why 2D? Maybe more stealthy?

Better at suppressing the IR signature of the aircraft. At long ranges the F-35’s IR sensors could have picked up a standard J-20, but with 2D TVC nozzles that will be reduced. Not sure by how much but probably a significant amount.

Also from what I remember reading somewhere the F-22’s 2D TVC nozzles were so heavy that they required 15% more thrust from the engines to have the same performance then if the aircraft didn’t have the 2D TVC nozzles. The WS-15 is going to have to reach the 180/190 Kn design specs if the 2D nozzles are to be accommodated.

 

[IblinI]

Also from what I remember reading somewhere the F-22’s 2D TVC nozzles were so heavy that they required 15% more thrust from the engines to have the same performance then if the aircraft didn’t have the 2D TVC nozzles. The WS-15 is going to have to reach the 180/190 Kn design specs if the 2D nozzles are to be accommodated.

I read from somewhere that said this is not going to be the case on our TVC, but forgot of how.

 

[FuturePAF]

I read from somewhere that said this is not going to be the case on our TVC, but forgot of how.

I don’t recall the full details, it was perhaps more than ten years ago I read this, but the weight had something to do with keeping the stealth intact. Perhaps lighter materials have been developed since.

 

[Beast]

Better at suppressing the IR signature of the aircraft. At long ranges the F-35’s IR sensors could have picked up a standard J-20, but with 2D TVC nozzles that will be reduced. Not sure by how much but probably a significant amount.

Also from what I remember reading somewhere the F-22’s 2D TVC nozzles were so heavy that they required 15% more thrust from the engines to have the same performance then if the aircraft didn’t have the 2D TVC nozzles. The WS-15 is going to have to reach the 180/190 Kn design specs if the 2D nozzles are to be accommodated.

Yes, the Russian try the 2D vector before. Too heavy and mass loss of thrust. That is why they go for 3D vector which gives them more angle control.

 

[White and Green with M/S]

Yes, the Russian try the 2D vector before. Too heavy and mass loss of thrust. That is why they go for 3D vector which gives them more angle control.

Does stealth is more important for SEALTH JET or anything else like thrust or agility, let wait and see what will TVC tech uses by J-20 for WS-15 engine, if STEALHNESS is more important for PLAAF than it will go to 2D TVC, if not than PLAAF will go for 3D TVC

 

[LKJ86]

Yes, the Russian try the 2D vector before. Too heavy and mass loss of thrust. That is why they go for 3D vector which gives them more angle control.

No, Russia is using 2D TVC nozzles, instead of 3D TVC nozzles.