[PapaBear3625]

I wonder how well it can “see” the F-22?

[Yo-Yo]

When the F-22 is supercruising at mach 1+ with its leading edges heated up, and at 65,000+ feet against a cold background sky, IR can see the F-22 very well indeed.

Good thing that Russian fighters don't carry IRST pods, and even if they do it's a good thing it's on the underside of the aircraft were it can't look up. Oh wait...