Actually Mig, when you go back to ancient history to make your point, it is often not cogent to the discussion, The F-22 is a known quantity, it performs very well in each of the fifth gen arenas, and what is not published may be extrapolated from what we do know.... How well J-20 or T-50 perform is largely projection, although no doubt there is some hard data on each by now, there are some rather simple formulas for arriving at actual performance projections such as thrust, weight, wing area, OVT or straight nozzles. There are pilots and engineers who can plug this data into their own onboard computers and make performance projections with a high degree of accuracy. AFB
Let me explain more my point.
Usually in forums, people say whatever they want, if a person is a fan of a canarded aircraft like J-20, Gripen, Rafale, right away points the combination canard-delta wing.
If they like F-22 they claim automatically the F-22 is superduper, if they are Pro-Russians well right away TVC nozzles and LEVCONS.
But the true reality, a realistic assesment of an aircraft is made by its manual or if they capture the aircraft or get a copy via legal ways.
In the case of F-5, the Russians got even manuals from the Vietnamese plus the airplane.
In the case of MiG-21, MiG-23 and MiG-29 the US got manuals via Egypt, Germany and later Belarus plus the airplanes.
Other way is they get the pilot like MiG-25 they got belenko and inspected the MiG-25 in Hokkodate airport or MiG-15 they got pilot and plane.
Engineers of course have supercomputers and in the case of Russia they do claim T-50 will beat F-22.
However if you see most forums their assesments are made upon hunches, biases or feelings.
The good thing of having a captured plane for an air force is actually they can really test mock combats, these days they try to do it in Red flag, or the Sino-russian exercises where they do see a bit of their peers strength.
In red flag they have tested Su-30MKIs versus F-15s or Eurofighters.
India has tested Su-30MKIs versus Eurofighters, F-16s and F-15s.
However J-20 is a total mystery, first the jet only flies in China, people can not even be 100% assure what engines it has, or what engines will it have.
So at the end, we get very limited information, plus an assesment is not always accurate.
Take the case of the Zero or MiG-25, for example, the Zero was dismissed as a inferior fighter by western analysts right away, the result was the Zero was better than most western aircraft it faced up to 1943 and that change when they actually got access to a real Zero and tested flight it versus other american fighters.
The Russians did the same to many German WWII aircraft.
With Manuals you get realistic performance data, for example the USAF and Luftwaffe trained their pilots since 1990 with real MiG-29s, just 8 years after MiG-29 entered service, their early assesment was in dogfights the MiG-29 in 1990 to up to 1999, was the best dogfighter in the world, they knew it by Manuals and actual mock combat between F-16s and MiG-29s .
Now aircraft change with variants, for example Spitfire IX was better than Fw-190, but F-190 was better than all the earlier variants of spitfires.
To cite you an example, most western pilots had access to MiG-23s of early generations or the dual trainer, which were not the best variants, same is applyable to MiG-29s or Su-27s.
So my whole point is we do not have a realistic J-20 performance assesment simply because one, this is a forum, where people opine based upon feelings without even having specifics of what altitude, speeds a fighter is better than others.
Second these jets are prototypes.
True with aerodynamics you can see what compromises it has, what might be its weak points of any aircraft but...that is not the whole picture
So in that sense i agree with Deino, sometimes is just better get the pop corn, and see the latest video of J-20 and see the latest picture and really just enjoy the video without any comment of how good is J-20.
