>a plane will know a radar is active long before the radar can detect the plane. The other bit of information that might be perhaps missing from some (other!)

>a plane will know a radar is active long before the radar can detect the plane. The other bit of information that might be perhaps missing from some (other!) explanations is that this arises entirely because the ground station has to receive a radar reflection _of the original beam_ from the target. Given that power goes as 1/r^2, this means that in practice range drops off sharply for the ground-based station as 1/r^4. Meanwhile, the aircraft can just _detect_ some sort of blip-over-thermal power spectral density coming from somewhere. Given identical amplifier performance (which, with good designs, should be limited by physics) and you end up with the attacking aircraft "winning" from a back-of-the-envelope point of view. This ignores the fact that it can be traditionally quite easy to confuse radar by "just" transmitting the "right" signals at the right time. There's a good 1960s video that explains a lot of the basic ideas here: https://www.youtube.com/watch?v=pyFqaaqqph0 https://www.youtube.com/watch?v=pyFqaaqqph0