I found some information which may corroborate some of MiG-23MLD’s assertions. It’s a little vague and does not mention Ye-152A by name. But it confirms Chinese designers used Soviet aerodynamic studies during the design of the J-8. It does not however support the conclusion that the J-8 was copied from something else.

This excerpt is from an interview with chief aircraft designer Wong Nanso (王南寿), who was in charge of the J-9 project which competed with and lost to the J-8 team. It discusses the competition between the two projects and the challenges the designers faced, especially his J-9 team.

王辉：我国的航空工业与苏联航空似乎有着千丝万缕的关系，您认为苏联航空技术对我国都产生了哪些影响呢？

王老：如果没有苏联手把手教，我们完全是空白的。＂东风＂１０７的设计队伍里还有苏联专家呢，包括歼８的一些气动特性，我们都参考了苏联的一些设计成果。当然，＂师傅领进门，修行在个人＂（笑了）。

Translation:

Wong Hui (journalist): Our aviation industry and Soviet aviation seem to have a thoroughly intertwined relationship. What influences do you think Soviet aviation technology have had in our country?

Wong Nanso: We wouldn’t have anything without hand-in-hand tutelage from the Soviets. Even the Dongfeng 107 (early Chinese supersonic fighter) design team included Soviet experts. Also regarding some aspects of the J-8 aerodynamic characteristics, we studied some results from Soviet design. Of course, “the abbot can open the door to the monastery, but spiritual achievement is up to the individual”. (laughs)

_________________

Source:

http://bbs.meyet.com/dispbbs_24_146814_1_116.html

The question it is not like you think, an aircraft takes many hours only of wind tunnel test for example the Su-27 took an equivalent of 20000 hrs or an equivalent in work time of several years around 8 years in fact only big aircraft like the Boeing 747, Tristar or space shuttle took more hours of wind tunnel

But the J-8 is not as complicated as the Su-27. In fact it’s a 1950s era design built in the 1980s. That it took so long to mature wont make a lot of sense if substantial design work were already done by the Soviets. The amount of time put into this project suggest it’s entirely likely an indigenous product.

If a country could make the MiG-21 and its engine, the J-8I is the simplest and most obvious way forward.

Although you say there are Russian sources who make the claim that J-8I is Ye-152 based, it is also entirely possible that they are wrong. Just as your source wrongly represented Lavi specs as J-10 specs on the other thread. The trouble with internet sources is that people copy and paste without careful scrutiny. And after awhile it becomes accepted fact. This happens all too often for internet reference to be taken seriously.

To establish your claim as fact you’ll have to provide more than that. What you have done so far is establish motive (yes the Chinese would have loved to have data on the Ye-152), and circumstancial report that it happened.

What would be more convincing would involve a detailed story on who, when, what, and how this transfer was made. For example a magazine article including interview with Russian designers claiming personal involvement would be strong evidence.

I don’t know what the fuss is all about. The Chinese wanted a twin engine MiG-21, they got it. They were probably aware of the Ye-152. But why do they need the Ye-152 documents when they already got the MiG-21 as template? Doesn’t seem that big of a leap.

I wonder why no one is testing an electrothermal/chemical catapult, whereby an electromagnetic coil is used to superheat a liquid.

I could see China and Pakistan developing another fighter together. Maybe some of the Islamic ASEAN countries would want involvement at some level. Perhaps a more affordable JSF type ac?

If the South Koreans want to cooperate with someone it’s going to be the Americans or Europeans. There’s no way they will be working with the Japanese. They might conceivably work with the Japanese or Chinese on civil aircraft, but military? No chance.

Aren’t the Americans taking a long hard look at hypersonic interconternental bombers? Thats a damn good reason for a dedicated interceptor right there.

Also, high speed interceptors could be fairly good counter against stealth ac. For example, if you use long frequency radio waves, you have a decent chance of getting a readable return from stealth planes, but the data is not good enough to guide a SAM with, so you send in your high speed interceptor instead.

Against the likes of the B2 and F117, it would be an easy kill as soon as the interceptor detects them. Even against the likes of the F22 and F35, if you have a M4+ plane, you can just spam missiles at them as you make a pass, and so what if the F22/35 can outdance you? At full speed you can easily outrun their missiles and head home to refuel and refit to try it again.

I have been wondering how stealth fighters would handle something like the Republic XF-103.

Besides the helmet ruling that out—the J-11 pilots use a different helmet—the arrangement of the back view mirrors would rule out an Su-27.

Su-27, Su-30MKK, J-8F and J-7G pilots all use the same helmet with the HMS attachment. Everyone else uses this one.

I think this is a J-11 backseater. No reason for him to be wearing a helmet with HMS.

As the calculator link from Adrian showed you have to add the height of the target in mind to get the theoretical radar range. Example there showed optimum conditions, flat sea, a big ship, no other distracting things around and all systems at 100%.

Yes I took that into account, but it’s unlikely the Russians flew that mission at high altitude.