in general the argumentation seems well built, my main comment is that there are some assertions for which I have not seen evidence.
Backman wrote:In contrast to Su-35S, PAK FA has more powerful engines, better T/W ratio, greater wing surface/lower wing loading, better acceleration/climb rate, better turning characteristics, in essence significantly better than Su-35S according to test pilot Сергей Богдан.
This is the key point, where did he say that, I have personally not seen it. Engines are more powerful, Bogdan even said one needs to be careful with the plane because you can go supersonic before you notice... but I don't know how it is with the Su-35, in any case it sounded as if he was surprised by it and so a substantial improvement vs. Su-35S, but that is only an opinion.
Again, weight unknown, so is T/W so wing loading, acceleration. I have not seen Bogdan saying the Su-57 is more manoeuvrable than the Su-35, do you have links?
And all that using interim engines. Final version of the engine will have 15 to 25% higher thrust, lower specific fuel consumption and about 30% lower specific weight according to manufacturer.
Manufacturer has said that? Would love to see it.
15-25% higher thrust could be meant in mil settings, since it is supposed to be a supercruising engine, but maybe not in AB, since that would mean between 17 and 19 tf (!) for an engine the size of AL-31F. Marchukov said SFC was that of AL-31F. I have not seen that reference of 30% lower specific weight and I find it difficult to believe, izd. 117 is already below 0.1 (TWR for the engine would be above 14!)
PAK FA is F-22 class fighter that is designed to fly very high and fast (did I mentioned that variable intakes help a lot). It is also designed to supercruise at speeds that are probably higher than F-35 top speed, it is designed to "live" there for a long period of time. There is great SEP reserve compared to F-35 in supersonic region when PAK FA is using burners. When F-35 has no more SEP at 1,6 Mach, PAK FA continues accelerating to +2 Mach. This is clear indication of superior transonic/supersonic acceleration.
This is hard to dispute. The AIAA paper studying the EM characteristics of the F-35 shows very poor supersonic performance, which is something almost everybody suspected regardless. The designer and services have admitted supersonic flight regime is not the main goal of the F-35, whereas in the Su-57 this is one of the main priorities. I can only expect it to be head, shoulders and waist above the F-35 in that regard, more when the izd. 30 appears. BTW, the F-35 has still excess power at 1.6 M, but apparently not much.
In other words F-16 block 50 would be very dangerous for F-35 in guns only scenario. Start putting some missiles and F-35 takes the advantage. And I do agree. That is absolutely more realistic scenario! The problem here is we are not comparing F-35 to F-16, we are comparing F-35 to PAK FA.
Here the only advantage of the F-35 is having a monster engine. The F-16 with such an engine would utterly crush the F-35...
As we already know PAK FA is superior to Su-27 and we can see that Su-27 is superior to F-16 block 50.
The comparison with the Flanker is very well built, but the translation to the PAK-FA is a bit of a leap of faith, since we don't know how much better (or not) the plane is in all flight regimes compared to Su-35. Not that I remotely think the F-35 would fare very well, but a quantitative comparison is still not possible.