Maybe, it depends on how the problem is stated. A couple of things: - is it a mission that requires 1 continuous flight? That would be very difficult to accom

Maybe, it depends on how the problem is stated. A couple of things: - is it a mission that requires 1 continuous flight? That would be very difficult to accomplish. You need a lot of fuel to go that far, which in turn increases your mass, which increases your fuel requirements, etc. - speed requirements? How long do you want it to take? It may be possible to use a balloon and take advantage of wind + solar power. - size? route? service ceiling? None of these are defined very well so it's hard to say. My guess would be it'll probably be very difficult to accomplish without being detected by someone.