Wouldn't it be an order of magnitude easier to make a simple gas powered balloon? You could hook it up with an altitude sensor and make sure it doesn't drift away.

Simpler yes, but where does the gas come from?

how do you make sure it doesn't drift away?

unless you combine the plane and the balloon into the zeppelin...

Have you written about this somewhere? It's an intriguing idea that I'd like to read about. Did you go so far as to explore the technical issues? I recently got into UAVs because of http://diydrones.com/ and their ArduCopter http://code.google.com/p/arducopter/

Well, in the United States at least, it is illegal to operate a drone unless you: A) have direct line of sight with the drone and B) can manually take over the drone at any time. This means you would need to have someone watching each drone unless you can successfully hide its operation from the government, which could be difficult since its mission is to relay electromagnetic signals back down to earth.

good point, but i think the original intent is to transmit information if the government began to censor the net. Therefore, you can imagine _anything_ you do is going to inhibit the free flow of information, therefore you're just as sensible to go ahead and and run some nice drones. :)

Bingo.

There are multiple mission scenarios and our intention is to support as many as are practical.

I wouldn't think you could provide enough power via solar to make up for the weight of the panels. What's the expected life on these?

NASA has flown a few prototype solar powered UAVs. See wikipedia for more info: http://en.wikipedia.org/wiki/NASA_Pathfinder

I think this was on HN the other day actually:

http://www.defencetalk.com/zephyr-solar-powered-uav-soars-to...

Weather balloons?