Yes. Although I would go with a high-altitude aircraft with low radar signature. A 1 kg payload is small, and other than the engine the thing could be mostly no

Yes. Although I would go with a high-altitude aircraft with low radar signature. A 1 kg payload is small, and other than the engine the thing could be mostly non-metallic. Flying over terrain is hard. Wind shear is a huge issue (I've seen situations where there was a 20 knot wind at ground level and still air at 100 m) as is turbulence and stuff in the way (trees, rocks, mountains...) I've often wondered if a combination of storage batteries and solar panels could give you unlimited range (for some part of the Earth, at least, during some times of the year: high latitudes in the summer, say.) A high altitude design would also facilitate that, as power consumption could be minimized during the dark hours at the cost of losing some altitude (simply gliding through the night is not possible with any reasonable design parameters.) The total cost of such a project would be low enough that I'm a bit surprised no one has done it yet.