Originally Posted by
meleagertoo
Quite how an IR homing missile manages to 'see' the cold-soaked payload is strange, or does that version of Sidewinder have radar homing too?
According to public domain info things have very much moved on with heat seekers since the days of things like the 9G and 9L which needed to the seeker to "see" a hot spot/hotspots.
The 9X (and some other modern heaters) uses some fancy technology to image the target in the IR (and anything with a temperature above
absolute zero is emitting IR to some degree) and then the missile flies a suitable course towards the image....amongst other that increases the resistance to being decoyed by flares and perhaps (rumour) even the ability to select a vulnerable bit of structure to aim for.