At that point you are well past "models" and in to "UAV" land. There are a lot of UAV companies out there who do that sort of thing, and it's not as easy as you might think. Also, the FAA has been taking a real dim view of unpiloted aircraft wandering around in "their" airspace recently. (there are guys from several UAV companies in my club, and we've talked about their stuff and their dealings with the FAA. Sounds like a real hassle).

Needless to say, it's also against the AMA safty code and will void AMA insurance, but you didn't say you were or weren't an AMA member so that might be a moot point.

However, you should keep in mind what could happen if your UAV crashes in to something valuable. The UAV companies have a hell of a time with insurance.