All J-11B are new built. It's not an upgrade for existing airframes, but of course is the J-11B based on the Su-27SK. Despite the fact that the S-u27SM is an upgrade for existing Su-27 it features very similar improvments of the Su-27 like the J-11B.
If SAC can only improve J-11B to SM level (which is basically around MK2), then it will get zero order from PLAAF.
Really? With new air frame and everything? Because otherwise it's not a brand new plane it's just a really big upgrade.
I was asking because I thought the J-11B is supposed to be a standard J-11/Su-27 with extensive upgrades making it approach, match or even exceed the Su-30 in some aspects.
I was wandering if the Russian Air Force was going to do anything that comprehensive with their Su-27 fleet (e.i. giving them multi-role capability).
well, it's definitely lighter, uses a lot more composites, different engine, a digital FBW, complete different set of sensors and a much more power radar. su-30mk2 is a pretty low standard.
As for how J-11B compare to su-35 in a few years. In terms of RCS, there is simply a limit to how much each can decrease by. They can easily put the upgraded WS-10 engine into J-11B by the time su-35 is ready. Which means, su-35 will not have any kind of advantage in that area. In terms of missiles, China has always preferred PL-12 and PL-8B over R-77/R-73. And in terms of radar/avionics, I certainly think China can match anything that su-35 brings. I know there are a lot of news on Irbis. China has actually tried it out and found it to be a very good radar, but just not as good as the Russians advertised. Certainly, it's current radar on J-11B is at least comparable in tracking range to Irbis.