Radar is radar at the end of the day, doesn't matter whether it's mil or civvy, same as dynamite, both versions go bang. I'm not sure what you're driving at when you say 'is it possible that it wasn't detected?' If it was in radar range then yes it would be detected unless it had some Klingon cloaking device. But if you are in the business then you already know that surely.
Well, it's a long time since I have been in an ATC or military radar room, that's why I'm asking. I thought primary radar returns are not displayed on current civilian ATC radars, at least not in normal operations. So civilian radar may not have noticed.
Military air defence radars however.... That is what I am getting at.
Is it possible the Air-force sometimes is asleep, or have lost the tapes? Was the only radar switched off and they were all down the local brothel? I have no idea as to the extent of Malaysia's air defence capabilities. I thought someone here might know.