HC, do you really fly around willy-nilly in IMC at less than 500'? That's the only way I can think of in which moving rigs could be a problem. I consider moving rigs to be a complete red herring, and not worth the trouble of worrying about. In any case, a mobile drilling rig presents a rather large radar signature, and can easily be seen on the radar display. If you don't fly over an unknown radar target, your danger is certainly minimized. At least over here, we cannot fly an offshore approach without operable weather radar in ground mapping mode, and must avoid all radar targets. I simply don't understand your continued objections to improved technology.
212man, don't knock the Trimbles. That's what I'm still using. Sure it's hard to use, gives no situational awareness, has the worst user interface anyone could ever dream up, but it's still better than the TD711 LORAN I had before it came along.
