knowan wrote:milosh wrote:design is VLO if Su-57 have radar blocker and stealthy nozzles.
Doubtful, given the poor RCS of the Su-57 even without the visible engine faces and nozzles being modelled:

All three graphs are from different authors which imply different methods and conditions.
But let we say they are same.
So Frontal RCS is close to F-22.
So frontal aspect is definitely stealth design something which people tried to disprove on this forum from 2010, pushing nartive about clean 4.5gen at best in frontal RCS.
Now let we look side RCS. Graph isn't easy to analyse because there are four frequencies instead one but if you look in tables max side RCS is ~14.2 dBsm which is ~25m2, F-22/35 max side RCS from graphs is ~5dBsm or 3m2
While 3m2 look much smaller then 25m2 it isn't similar to VLO vs non VLO comparison. For example radar which can detect 3m2 from 100km will detect 30m2 from 200km, so Su-57 would be detect from less then two times longer distance then F-22/35 by same airborne radar, if we analyse your graph comparison and table values.
Rear RCS is pointless to compare because Su-57 model is without stealth nozzles.