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[mcnews]

Originally Posted by Alan D Segal

So they don't need radar? Best let the folks at the airport know then.

They have both as a fail safe of course. The radar aerials you see at airports have the big dish for detecting skin and the narrow rectangular box is for the reception of the IFF signal.

I know this as I was in a previous life a military aircraft controller (not just airspace management type ground control stuff but more exact close quarters maneuvering and airplans along with direct control of aircraft in relation to my ordered heading, speeds, altitudes and weapon selection and firing on my command etc.) with all sorts of experience with various radar systems. Military also uses IFF around airports also by the way, they also have a few extra modes of IFF over and above the civilian modes.