Chengdu J-10 Multirole Fighter Air Craft News & Discussions

[Nein]

This has been debate for more than ten years. Simple answer is no.

J10 is a further development of cancelled J9 (pix below), and J9 pre-dates F-16/ Levi.

View attachment 565783

Okay thanks I was just wondering about it. Basically proves the point that China's jet fighter program was basically started from scratch than the usual China stole this or copy argument which a lot of people love to use.

 

[Deino]

I dont want to troll or ask a stupid question but I read the J10 is based on the cancelled Israeli IAI Lavi jet fighter.

It is said that Israel sold the design and everything to China.

To any Chinese members how much of this is true?? Or is it just a lie?

This controversial question pop-up time and again. Israel denied it. China also denied it. So the answer is no, J10 is not Lavi, is this the answer you are looking for?

The point is, it is de fact not a copy and everyone who denies this is as stupid as those who claim the FC-31 is a clone or 1:1 copy of the F-35. Just look at the size, the dimensions and so on, It cannot be a copy albeit is is surely influenced by it and borrows certain design characteristics in the same way the FC-31 is similar to the F-35, or the Airbus A320 to the C919.

On the other side, it is also undeniable that there were some closer contacts between IAI and CAC as proven by this image showing the IAI Lavi + a Chinese delegation including Song Wencong somewhere in the 198xs.

This has been debate for more than ten years. Simple answer is no.
J10 is a further development of cancelled J9 (pix below) with revised air intake, and J9 pre-dates F-16/ Lavi.

Yes for sure, but it is also undeniable, that there were contacts ... and we all know also how the J-9 evolved thru a very-Lavi-like design to the final J-10 as we know it today.

 

[lcloo]

The point is, it is de fact not a copy and everyone who denies this is as stupid as those who claim the FC-31 is a clone or 1:1 copy of the F-35. Just look at the size, the dimensions and so on, It cannot be a copy albeit is is surely influenced by it and borrows certain design characteristics in the same way the FC-31 is similar to the F-35, or the Airbus A320 to the C919.

View attachment 565784 View attachment 565785

On the other side, it is also undeniable that there were some closer contacts between IAI and CAC as proven by this image showing the IAI Lavi + a Chinese delegation including Song Wencong somewhere in the 198xs.

View attachment 565786




Yes for sure, but it is also undeniable, that there were contacts ... and we all know also how the J-9 evolved thru a very-Lavi-like design to the final J-10 as we know it today.

View attachment 565787 View attachment 565788

Yes, it is true that Israelis did help, mostly I think on solving technical difficulties encountered by Chinese during J10's development. Instead of direct copy the Lavi design, plane form design based on Lavi might take place to solve aerodynamic issues.

Lavi's development is strongly influenced by Mirage III, Kfir fighter jet and F-16. J10's design is heavily influenced by the 1970s era J9, with probable assistance on modernised design from Israelis. However, it would be incorrect to describe J10 is a copy of Lavi.

Israelis were quite close in technical cooperation with China in may fields, until they were told to stop by the Americans.

 

[serenity]

Deino's answer is perfect.

Israel's involvement and help with J-10 program is in highest degree in area of fly by wire systems. So many national efforts dealing with designing complex FBW and there was assistance from Soviets and Israel. Although their assistance helped by who knows how much, the accepted beliefs are they were at least a little bit involved. J-10 has certain resemblance to Lavi just like F-15 has certain resemblance to Mig-25 or Airbus has with Boeing and Eurofighter has with X-31. However the balance, airflow, controls, and other important aerodynamic considerations between the J-10 and Lavi are different enough to force J-10 designers to completely use a totally different set of flight controls. This is real engineering and not simple look and copy. The details are so important and overlooked by stupids who cry copy all day. Now the fundamental design of canard and layout is following Lavi's certainly just like a year 2000 BMW design layout may follow a year 1999 Benz. That's as far as the important things go.

What is really important here is actually the FBW and apparently the assistance from Israel. This is unconfirmed but suspected theory by many. Officially Chinese authorities are quiet so even if true or false, they won't say because it doesn't matter to them and will continue to not matter in coming years.

 

[jaybird]

Low flying J-10 from OedoSoldier.

https://twitter.com/x/status/1141214580355428354

 

[Deino]

https://twitter.com/x/status/1151471325648760832

 

[Su33KUB]

Deino's answer is perfect.

Israel's involvement and help with J-10 program is in highest degree in area of fly by wire systems. So many national efforts dealing with designing complex FBW and there was assistance from Soviets and Israel. Although their assistance helped by who knows how much, the accepted beliefs are they were at least a little bit involved. J-10 has certain resemblance to Lavi just like F-15 has certain resemblance to Mig-25 or Airbus has with Boeing and Eurofighter has with X-31. However the balance, airflow, controls, and other important aerodynamic considerations between the J-10 and Lavi are different enough to force J-10 designers to completely use a totally different set of flight controls. This is real engineering and not simple look and copy. The details are so important and overlooked by stupids who cry copy all day. Now the fundamental design of canard and layout is following Lavi's certainly just like a year 2000 BMW design layout may follow a year 1999 Benz. That's as far as the important things go.

What is really important here is actually the FBW and apparently the assistance from Israel. This is unconfirmed but suspected theory by many. Officially Chinese authorities are quiet so even if true or false, they won't say because it doesn't matter to them and will continue to not matter in coming years.

Lavi had not a single aircraft configuration but several, in order to choose one they had to test different aerodynamic variants just for a canard or wing besides the structure uses several new innovative solutions that implies thousands of research hours, this transform into data, that data can be sold and that data offers several different wings all customized to different flight envelopes, the aircraft are different, true the research is not, make an aircraft means many thousands hours of research, the research costs, time and money they simply bought the Lavi data ask Russian aerodynamic institutes to help, and their own research was cobble together with the Lavi information

 

[ozranger]

Aerodynamics wide, Lavi has the least contribution to J-10 development. Lavi has major design flaw and the Israelis have much less experience on delta-canard configuration than Institute 611.

From a couple of different sources, I can see that

- Israelis helped on FBW and especially hardware.
- Frenches helped on FBW design software and probably with some coding exercise. I guess they might sold some of their Rafale knowledge and experience.
- Russians helped on the engine.
- Aerodynamic design is a continuation of one of J-9 propositions.

 

[Deino]

Aerodynamics wide, Lavi has the least contribution to J-10 development. Lavi has major design flaw and the Israelis have much less experience on delta-canard configuration than Institute 611.
...
- Frenches helped on FBW design software and probably with some coding exercise. I guess they might sold some of their Rafale knowledge and experience.
...
View attachment 569927

Surely not. The Lavi was a most successful design, even so much that the US killed it since it eas a danger for future F-16 sales. So do say it it was a flawed design and had issues is plain wrong and simply false.
The number different design iterations of the J-9 is also irrelevant, since if you compare how many variations of the Lavi were studied, you would know that the Israeli had probably even more experience since they actually had flying delta designs in use at a time, when China was still trying.

Concerning the Rafale, this is simply impossible, since the design of the J-10 and its FCS was done, before before the Rafale demonstrator even flew.

So please do your homework before claiming nonsense.
Otherwise you are correct.

 

[Su33KUB]

Aerodynamics wide, Lavi has the least contribution to J-10 development. Lavi has major design flaw and the Israelis have much less experience on delta-canard configuration than Institute 611.

From a couple of different sources, I can see that

- Israelis helped on FBW and especially hardware.
- Frenches helped on FBW design software and probably with some coding exercise. I guess they might sold some of their Rafale knowledge and experience.
- Russians helped on the engine.
- Aerodynamic design is a continuation of one of J-9 propositions.

View attachment 569927

Lavi had a ITR higher with less TWR, carrying a higher fuel fraction than F-16, to put it simple a Lavi was capable to out turn an F-16 even having less thrust.

read this link
http://john-golan.blogspot.com/2016/05/lavi-engineers-perspective.html

research means the Israelites studied not only the configuration you know now as a Lavi, just to mention they studied several intake types and vertical tails configurations they had a twin tails on booms version without no ventral fins, another publicly known version was a Gripen look alike Lavi ,When the Chinese delegation visited Israel obviously they went to get not a Lavi because the Lavi had a very low power engine of american design, they went to collect data on all the lavi studies to adapt the Al-31 to their design the asked SiBbia in Russia to help to verify and refine the Chinese design, the J-10 has Lavi DNA not because they are identical but because data which is more important was transferred, data means all the different aerodynamic, structural data they could get, however aircraft have millions of parts so Lavi had thousands of suppliers, many in the west. so the Chinese by acquiring that data could replace with local content those suppliers, except the engine, radar and some avionics, but by acquiring the data the save thousands of research hours, and they could build a design that was more or less as advanced as a Gripen, the J-10 had a version almost as a Lavi


see post 16
https://forum.keypublishing.com/forum/modern-military-aviation/141218-israel-s-lavi-fighter-program

 

[ozranger]

Lavi had a ITR higher with less TWR, carrying a higher fuel fraction than F-16, to put it simple a Lavi was capable to out turn an F-16 even having less thrust.

read this link
http://john-golan.blogspot.com/2016/05/lavi-engineers-perspective.html

research means the Israelites studied not only the configuration you know now as a Lavi, just to mention they studied several intake types and vertical tails configurations they had a twin tails on booms version without no ventral fins, another publicly known version was a Gripen look alike Lavi ,When the Chinese delegation visited Israel obviously they went to get not a Lavi because the Lavi had a very low power engine of american design, they went to collect data on all the lavi studies to adapt the Al-31 to their design the asked SiBbia in Russia to help to verify and refine the Chinese design, the J-10 has Lavi DNA not because they are identical but because data which is more important was transferred, data means all the different aerodynamic, structural data they could get, however aircraft have millions of parts so Lavi had thousands of suppliers, many in the west. so the Chinese by acquiring that data could replace with local content those suppliers, except the engine, radar and some avionics, but by acquiring the data the save thousands of research hours, and they could build a design that was more or less as advanced as a Gripen, the J-10 had a version almost as a Lavi


see post 16
https://forum.keypublishing.com/forum/modern-military-aviation/141218-israel-s-lavi-fighter-program

J-10 just cannot reuse Lavi's aerodynamic data. Lavi has flaws in design on its canard and main wing combination. There is an article in Chinese discussing the issue,

http://dy.163.com/v2/article/detail/CU3AU8IF0515I1K0.html

In short, Lavi's pitch down control is terrible.

Look at the pictures in the article, you can see Lavi's design is very unique and somewhat gone extreme, while canard employed designs from other countries are all different to it.

Unless Israelis move the canards forward and change the main wings to delta wings, they just can't put that into final production.

Saying the Frenches sold their Rafale knowledge to the Chinese while they sold the FBW software would be a lot more credible.

BTW worth pointing out that JAS-39 is very similar to J-10 on canard and main wing combination.

 

[Deino]

...
Saying the Frenches sold their Rafale knowledge to the Chinese while they sold the FBW software would be a lot more credible.

Again, how could they have soll their Rafale knowledge if the first Rafale flew only mach later??? It makes no sense

 

[ozranger]

Again, how could they have soll their Rafale knowledge if the first Rafale flew only mach later??? It makes no sense

Maybe some early knowledge exchange between these 2 countries. Of course there is no credibility of such claim at all. I made that guess just for fun.

The sale of FBW software seems to be real as a couple of different sources stated that it did happen during the J-10 development.

 

[Deino]

.... Lavi has flaws in design on its canard and main wing combination. There is an article in Chinese discussing the issue,

http://dy.163.com/v2/article/detail/CU3AU8IF0515I1K0.html

In short, Lavi's pitch down control is terrible.

Look at the pictures in the article, you can see Lavi's design is very unique and ....

Please not trying to armchair-analyse ...

You take a Chinese fan-discussion for fact, while all other sources say otherweise ??

 

[Su33KUB]

J-10 just cannot reuse Lavi's aerodynamic data. Lavi has flaws in design on its canard and main wing combination. There is an article in Chinese discussing the issue,

http://dy.163.com/v2/article/detail/CU3AU8IF0515I1K0.html

In short, Lavi's pitch down control is terrible.

Look at the pictures in the article, you can see Lavi's design is very unique and somewhat gone extreme, while canard employed designs from other countries are all different to it.

Unless Israelis move the canards forward and change the main wings to delta wings, they just can't put that into final production.

Saying the Frenches sold their Rafale knowledge to the Chinese while they sold the FBW software would be a lot more credible.

BTW worth pointing out that JAS-39 is very similar to J-10 on canard and main wing combination.

If you read the article by Golan, you will see a detail Lavi was designed with higher lift thus it could out turn the F-16 at lower altitudes and speeds but it had lower thrust to weight ratio, so it accelerated poorly compared to F-16, and it turned poorly at higher speeds compared to F-16, why? the Lavi was not designed to intercept fast aircraft, and they chose a simple fixed ventral intake to reduce weight, so as an interceptor and air superiority was poorly suited, also on turn rate its lower TWR meant F-16 achieved higher STR specially at higher speeds.

the F-16 early configuration will lead you to see the F-16-Lavi-J-10 connection

J-10 is more suited as an interceptor, its profile is sleeker, and in the early version A it has a moveable intake ramp, when you look at J-10, it shares a common position for its ventral fins, coincidence? no it is not, Lavi tested a configuration of tail booms twin vertical fins of higher aerodynamic performance at high AoA than its single dorsal vertical fin and two ventral fins, but as on F-16, they went for single dorsal and twin ventral fins due to lower weight advantages, coincidence? no it is not coincidence because if you look at the wing position it follows the same solution and the single dorsal vertical fin and twin ventral fin reduce weight .
On the J-10, a two-dimensional variable intake air intake is used. Its shape changes due to two movable panels. This design meets the increased requirements for aircraft when conducting air combat. In addition, the use of a variable geometry air intake contributes to an increase in the dynamic pressure in the inlet device (by about 5% with M = 1.5, 15% with M = 1.8 and 25-30% with M = 2) . As a result, significantly improved engine thrust performance and its efficiency at supersonic speeds, which contributes to an increase in maximum speed and acceleration. The main disadvantages of using variable geometry air intake are the increased visibility of the aircraft when the radar is irradiated in the forward hemisphere, the size and weight of the structure increase, the attendant increase in the cost of the aircraft, and the need for additional maintenance of the air inlet control actuators


Look at the Eurofighter, Rafale or Gripen no ventral fins, this has to do with the position of the canard and intake type besides the size of the vertical fins, J-10 shares much more commonality with Lavi than with Eurofighter, its design of J-10 is an improved Lavi with a switch from ground attack role to interceptor/air superiority tasks.

Remember Israel had already F-16s and F-15s, so Lavi was designed as an aircraft it could dogfight if needed, but not as the main air superiority, F-16 went that way too albeit by powering it with higher thrust engines to allow to keep a similar TWR.