>>52461
>What were they doing that was so important that it was worth sending a valuable experimental assets like that for?
Maybe they aren't really experimental by now but combat ready and do missions for a while now.
>lost connection to the SU-57 or it lost the ability to fly properly. So it was uncontrollable and the SU-57 had to destroy it.
Now this really activates the almonds. Anti-drone EW capabilities can do more than disrupt frequencies, communications with various means: it is possible to take control over drones. Granted it is probably easier to do it with a DJI Mavic, than the S-70, but who knows. NATO is watching, they gather intelligence, draw conclusion, develop their own stuff, and they test weapon systems in Ukraine, partially by Ukrainians, partially by foreign "volunteers", they could test stuff covertly and directly themselves, as long as public does not know about. Russia has to turn a blind eye for different things anyway (like directing strikes on the Black Sea fleet from aboard of NATO AWACS and whatnot).
tl;dr NATO might have an EW system that can take the control over S-70s. They caught one and the Russian pilot had to destroy it.