SU-57 is designed not for stealth but to hunt stealth aircraft?

via Business Insider.

As the scientist said, Russia didn't even appear to seriously try to make a stealth aircraft. The Su-57 takes certain measures, like storing weapons internally, that improve the stealth, but it's leaps and bounds from a US or even Chinese effort.

This highlights the true purpose of Russia's new fighter — not to evade radar itself, but to kill US stealth jets like the F-35 and F-22.

The Su-57 will feature side mounted radars along its nose, an infrared search-and-track radar up front, and additional radars in front and back, as well as on the wings.

As The Drive's Tyler Rogoway writes, the side-mounted radars on the Su-57 allow it to excel at a tactic called "beaming" that can trick the radars on US stealth jets. Beaming entails flying perpendicular to a fighter's radar in a way that makes the fighter dismiss the signature of the jet as a non-target.

Any fighter can "beam" by flying sideways, but the Su-57, with sideways-mounted radars, can actually guide missiles and score kills from that direction.

Russia has long taken a different approach to fighter aircraft than the US, but the Su-57 shows that even without the fancy percision-machined stealth of an F-22, Moscow's jets can remain dangerous and relevant.

Haven't heard the theory that the SU-57 is simply a stealth killer and nothing else but it kinda makes sense.

Additionally I've never heard much about this side mounted radar arrays except from the Airpower Australia boys, but if this is right then we have to consider something else too.

The entire SU-30+ family has this type of radar or can accommodate it.  That means that there are tons of currently flying airplanes that can employ this technique.

But what about the Chinese you say?

They're looking to play the game we do.  They're looking to conduct offensive operations.  Additionally it is as I've always said.  For better or worse and in defiance of conventional wisdom, the Russians are BUILDING A DEFENSIVE force.  You can look across their entire defense industry and for the most part they're building for the defense with limited offensive capability tossed in (and even that is found in the use of weapon systems in that role, not purpose built stealth attack aircraft).