On a bunch of my addon aircraft, I have a radar made by Eric Marciano.
It comes up but it doesn't show any aircraft. I have done some tests by getting right next an AI aircraft in flight and turn the radar on but the plane doesn't apear on the radar.
Help sure would be nice.
It uses FSUIPC... not all downloads with it have authorization to use FSUIPC so on the ones that don't have it it won't work unless you BUY authorization from the ppl who make FSUIPC.