Chengdu J-20 5th Generation Aircraft News & Discussions

[Su33KUB]

In fact you are absolutely correct.

My country operates Su-30MK with TVC and they said they'll use it whenever they need tighter turn during dogfight. Tested against F/A-18, Mig-29, BAe Hawk, the TVC eases things up in getting to their tails enjoying smaller turn radius. Of course they'll use it wisely based on limit, avoid bleeding out which would end up being easy target for enemy missiles.

J-20 is a large & heavy aircraft that it's perfect only to have powerful WS-15 40,000lb engine each with TVC and preferably having fitted internal gun. J-20 needed the TVC for high altitude maneuvering apart from improving turn radius. Current turn radius is too big, better than the F-14 but no where near Su-27, F/A-18E.

thanks.

The J-20 only needs high thrust, I mean Eurofighter can keep up with F-22 just by having a very low wing loading and high thrust to weight ratio.

What I mean post stall is useful, but nowadays helmet mounted sights and highly off boresight missiles can do the same in combat.

Usually TVC nozzles are used to regain some agility lost due to weight without increasing thrust, to increase sustained vertical or horizontal turns an aircraft needs thrust.

So as long as WS-15 is fitted to J-20 there is going to be increses in sustained turn rates compared to a WS-10 or Al-31 equipped earlier J-20.

TVC nozzles post stall capability is mostly to have aircraft without post stall limits and this can be used to re-direct the nose at any direction while moving on a fixed direction or flight path, however this bleed energy, the thrust increase reduces the speed bleed thus sustained turn rates are increased.

So while a WS-10 with TVC nozzles increases turn rate, a WS-15 without TVC nozzles will do the same for J-20 without adding extra weight for the engine

 

[kungfugymnast]

thanks.

The J-20 only needs high thrust, I mean Eurofighter can keep up with F-22 just by having a very low wing loading and high thrust to weight ratio.

What I mean post stall is useful, but nowadays helmet mounted sights and highly off boresight missiles can do the same in combat.

Usually TVC nozzles are used to regain some agility lost due to weight without increasing thrust, to increase sustained vertical or horizontal turns an aircraft needs thrust.

So as long as WS-15 is fitted to J-20 there is going to be increses in sustained turn rates compared to a WS-10 or Al-31 equipped earlier J-20.

TVC nozzles post stall capability is mostly to have aircraft without post stall limits and this can be used to re-direct the nose at any direction while moving on a fixed direction or flight path, however this bleed energy, the thrust increase reduces the speed bleed thus sustained turn rates are increased.

So while a WS-10 with TVC nozzles increases turn rate, a WS-15 without TVC nozzles will do the same for J-20 without adding extra weight for the engine

I totally agree with you. At the mean time, they don't seem keen to add TVC to WS-10C. We'll wait and see what are they up to next, everyone is waiting for WS-15.

 

[Su33KUB]

I totally agree with you. At the mean time, they don't seem keen to add TVC to WS-10C. We'll wait and see what are they up to next, everyone is waiting for WS-15.

Future will talk

 

[clibra]

Better angles for watching J-20's turns.

https://twitter.com/x/status/1444329544433881099

J-20 needed the TVC for high altitude maneuvering apart from improving turn radius. Current turn radius is too big, better than the F-14 but no where near Su-27, F/A-18E.

Watch carefully, from 0:24 to 0:27, J20 made 180 degree turn within 3 seconds.
please show us clip of su27 or F/A18E/F with better maneuverability, thanks.

 

[siegecrossbow]

Watch carefully, from 0:24 to 0:27, J20 made 180 degree turn within 3 seconds.
please show us clip of su27 or F/A18E/F with better maneuverability, thanks.

I think that is due to the camera angle.

 

[clibra]

I think that is due to the camera angle.

Brilliant !

 

[ozranger]

I think that is due to the camera angle.

The telephoto lens of a Canon DSLR is a good reference in the video clip, as well as the tips of the hills or trees on the ground. So, based on those references, the video capturing device, probably a mobile phone, did not make any big and fast movement, or rotation if more specifically, when it was tracing J-20'S turn. J-20 did make such a sharp turn with a very small turning radius in very short time.

I don't believe it is very easy for the cameraman to move the telephoto lens rapidly as it is so heavy and physically challenging. I saw in the video he even gave up tracing J-20 for a short moment by dropping the lens.

The key point is J-20 did turn in a very small turning radius as seen with reference to background hills or trees. Is that possible the cameraman accelerated the video on those specific frames of turning? Look, if the actual turning speed were then any slower in such a small space, J-20 would have entered a stall and fell.

PS: I am not going to respond to Su33KUB as there is obviously nil value for doing so. BTW I am highly impressed by @siegecrossbow for his/her new avatar - excellent camera angle.

 

[Su33KUB]

Watch carefully, from 0:24 to 0:27, J20 made 180 degree turn within 3 seconds.
please show us clip of su27 or F/A18E/F with better maneuverability, thanks.

that is not possible, at that speed, a Max 25 deg/sec which is very high, it will take more than 3 seconds,.

You are quoting a 60 deg/sec which basically is not even real, J-20 must be flying at least at 400 km/h

consider that formula, consider the aircraft has a bank angle.

The J-20 in that video has a more realistic turn rate 18 deg/sec

Load Factors (Part Four)

Vg Diagram The flight operating strength of an aircraft is presented on a graph whose vertical scale is based on load factor. [Figure 5-55] The diagram is called a Vg diagram—velocity versus G load…

www.flightliteracy.com

 

[Su33KUB]

The telephoto lens of a Canon DSLR is a good reference in the video clip, as well as the tips of the hills or trees on the ground. So, based on those references, the video capturing device, probably a mobile phone, did not make any big and fast movement, or rotation if more specifically, when it was tracing J-20'S turn. J-20 did make such a sharp turn with a very small turning radius in very short time.

I don't believe it is very easy for the cameraman to move the telephoto lens rapidly as it is so heavy and physically challenging. I saw in the video he even gave up tracing J-20 for a short moment by dropping the lens.

The key point is J-20 did turn in a very small turning radius as seen with reference to background hills or trees. Is that possible the cameraman accelerated the video on those specific frames of turning? Look, if the actual turning speed were then any slower in such a small space, J-20 would have entered a stall and fell.

Realistic turn rates for J-20 are around 30 deg/sec Instantaneous turn rate and 25 deg/sec sustained and that is a very high STR. see

Mig 29'smaximum turn-rate of 28 degrees per second is better than that of the nimblest of West's fighters: F 16's 26 degrees per second. And its sustained turn rate 23 degrees per second is better than West's most advanced air defence fighter F 15's sustained turn rate of 16 degrees per second.

India buying MIG 29 from Russia – Part 1

‘Strength lies not in defence but in attack.’ – Marquis de Acerba Mig 29 test pilot, Anatoly Kvochur, was awarded ‘Hero of Russia,’ the highest honorary title of the Russian Federation, and The Order ‘For...

timesofindia.indiatimes.com

The J-20`s Zhuhai air demo is unimpressive, a realistic number is 30 deg/sec instantaneous and 21 deg/sec sustained and that will make as good as Gripen which is pretty agile, but the turns it made were in the region of 18 deg/second.


Sustained - approx. 20 deg/sec. Instantaneous - approx. 30 deg/sec.

Saab JAS 39 Gripen

The Saab JAS 39 Gripen is a fourth generation, lightweight multi-role combat aircraft built in Sweden.

www.fighter-planes.com

 

[clibra]

Realistic turn rates for J-20 are around 30 deg/sec Instantaneous turn rate and 25 deg/sec sustained and that is a very high STR. see

Mig 29'smaximum turn-rate of 28 degrees per second is better than that of the nimblest of West's fighters: F 16's 26 degrees per second. And its sustained turn rate 23 degrees per second is better than West's most advanced air defence fighter F 15's sustained turn rate of 16 degrees per second.

India buying MIG 29 from Russia – Part 1

‘Strength lies not in defence but in attack.’ – Marquis de Acerba Mig 29 test pilot, Anatoly Kvochur, was awarded ‘Hero of Russia,’ the highest honorary title of the Russian Federation, and The Order ‘For...

timesofindia.indiatimes.com

The J-20`s Zhuhai air demo is unimpressive, a realistic number is 30 deg/sec instantaneous and 21 deg/sec sustained and that will make as good as Gripen which is pretty agile, but the turns it made were in the region of 18 deg/second.


Sustained - approx. 20 deg/sec. Instantaneous - approx. 30 deg/sec.

Saab JAS 39 Gripen

The Saab JAS 39 Gripen is a fourth generation, lightweight multi-role combat aircraft built in Sweden.

www.fighter-planes.com

Please provide your calculation details of your 30/21 deg/sec results.
Don't tell me you did a simulation in your brain.
Don't tell me "I don't konw why but I just believe turn rate of J20 can not be better than mig29/gripen/F16"

 

[Su33KUB]

Please provide your calculation details of your 30/21 deg/sec results.
Don't tell me you did a simulation in your brain.
Don't tell me "I don't konw why but I just believe turn rate of J20 can not be better than mig29/gripen/F16"

180 deg in 3 seconds is 60 STR, that will be post stall, there is no postall maneovre in that video, in fact A Hornet can not get very good numbers above 500km/h.

What you are saying is fantasy, most aircraft even the most agile are in the region of 25-28 deg/s and here I am saying with TVC nozzles, your 60 deg/sec is fantasy.

 

[Crimson Blue]

I think it is possible for China to buy F-119 and F-135 from the US with full TOT. $100 billion is enough for the deal. But hell, this number is way too big. China must be crazy to pay this amount to buy technology

This comment deserves permanent ban of this member from all defense related forums on the internet.... !

 

[ozranger]

Please provide your calculation details of your 30/21 deg/sec results.
Don't tell me you did a simulation in your brain.
Don't tell me "I don't konw why but I just believe turn rate of J20 can not be better than mig29/gripen/F16"

Past experience tells me you are wasting your time. Don't go into it or your energy will bleed .

 

[Deino]

Oh well ...

China Likely Stepping Up Stealth Fighter Production | Air & Space Forces Magazine

Production of the J-20, touted by China as a stealth fighter, is set to increase, with one US lawmaker saying the inventory could soon challenge the US.

www.airforcemag.com

... if this is the USAF's official understanding on the PLAAF's J-20, so what what an epic fail!

1. Not sure, what Zhuhai Airshow they saw, but 15 J-20s in a formation? Here on earth? What?
There were only two and no "additional group of the aircraft parked on the runway."...

But even more:

2. Why still citing SCMP? Minnie Chan is probably the most unreliable source and this report was criticised as simply wrong. To claim there are 150 J-20s in service is ridiculous all the more in "four air regiments, most operating in the interior of the country"
At best there 60-70 J-20s in service yet and the PLAAF operates them in Brigades!

As such, PLEASE beware of such reports and even more the mentioned "source".

In fact, I rate her the most unreliable "source" at all; I would even go as far that she has no true internal PLA-related sources at all. All she does is lurking around at some certain social media platforms and picks up the most obscure rumours, she then hypes as "based on internal contacts ...".

So, by my understanding, she's simply not able or willing to differ between reliable and unreliable internet rumours and to put them into the correct context.

 

[kungfugymnast]

Watch carefully, from 0:24 to 0:27, J20 made 180 degree turn within 3 seconds.
please show us clip of su27 or F/A18E/F with better maneuverability, thanks.

The J-20 is already banking when the camera started recording on the turn radius. I calculated few times minus the bad camera angle, it took 9 seconds to complete the 180degree turn and the turning radius is actually big compared to Su-27 and F/A-18E. There's no manned aircraft that could perform 60 degree turn per second unless it's an AIM-9X sidewinder missile.