I don't care about others, I am just curious to see how the thing will look like
That interest is perfectly normal, but why do you think they should reveal everything before they are good and ready... they don't have a currently flying B-2 analog so they need to test to make sure it works... and they are hardly going to risk an expensive stealthy drone with flight testing... make a cheaper simpler model to test to work out the problems... isn't that just obvious common sense?
First thing any defense company does is to show CGI or scale model of new product but forr Russian ones it's the last and apparently hardest thing to do
Why... it wont be for export for quite a while yet...
You show a CGI video if it is for export to see what potential customers are interested in joining the programme and helping with funding or contributing components... not really relevant in this case is it?
Does the flat nozzle suggest it won't be supersonic
Would suggest an attempt to make it more stealthy... a rectangular exhaust on a low bypass turbofan engine makes the hot air flowing through the core turbojet section mix more rapidly with the cold air moving through the bypass section of the engine leading to rather less IR signature.
Of course with the F-22 it works at supersonic speed and it probably simplifies the design of the engine exhaust to a 2D TVC instead of a 3D one... probably making it cheaper and lighter...
There was never a chance it would have been supersonic, wing type precludes it
This is a thin profile wing... the only reason it could not operate at supersonic speeds would be cg shift at transonic speeds... something an all moving tail plane was needed to fix going from the MiG-17 to the MiG-19, but there is no reason why a vectored thrust engine couldn't be used to compensate for the cg shift instead of a tail plane.
We now know that Sukhoi intends to make its unmanned combat air vehicle very stealthy, which will help overcome some of the Su-57's shortcomings.
But not its biggest shortcoming of not being American....
It usualy means less thrust
If I remember correctly testing of flat nozzle attachments for the engine on the Flanker resulted in a 15% loss of thrust, for an improvement of about a 30% reduction in IR signature or something.
Obviously with flankers it wouldn't matter, but I suspect the test info was more for the PAK FA than for the Su-35 developments.
Back in the real world, all stealth air craft will have some angle
from which their cross-section is very large.
Especially in frequencies they were not designed to be low observable to. Like visible light, where they are actually rather easy to see and track through the air... especially in that grey or the B-2 Black really stands out...