hesham said:
why we always refuse the new
I will modify your question a bit: Why we are so prospective when we find some "fantastic" new information? Because there is a loooot of fakes, misinterpretations and personal imagination, so being a skeptic and rational/evidence based is a good thing to do.
So, now when we have a source... how thrustworthy it is? What I find interesting/suspicious are also other listed projects such as:
izdeliye 41 - The project is a light tactical fighter, 1981 г 1981 . . Нормальной аэродинамической схемы, боковые ВЗ, ТРДДФ тягой 10 т (на 2-м этапе), БРЛС «Комар» Normal aerodynamic configuration, the lateral VZ, turbofan thrust of 10 tons (at the 2 nd stage), radar is "Mosquito"
izdeliye 4.12 - The project is a light tactical fighter 5 th generation (Project-21 - "Fighter of the 21 st Century) 1998 г 1998 . . С РЛС с АФАР «Жук-МАЭ», ТРДДФ тягой 11,5-12 т With radar AFAR "Zhuk-MAE", turbofans Thrust 11,5-12 m
izdeliye 1.27 - Draft medium tactical fighter 5 th generation, 1998 г 1998 .
Regarding the 901, if the 1990 is really the year, it can be something similar to Tupolev Tu-300. It means at best semi-autonomous RPV, able to deliver weapons in a medium distances. I am going to write to the author.