Unmanned Aerial Telecom Relays
Brussel writes "SkyTower in collaboration with the Japan Ministry of Telecommunications (CRL/TAO) and NASA has successfully completed a series of commercial telecommunications tests -- the world's first from more than 60,000 feet in the stratosphere. The tests, which began three weeks ago, were conducted from Pathfinder-Plus, an unmanned solar-electric aircraft developed by AeroVironment." There's another press release here.
Yes they would; lower fuel consumption, much greater endurance, less risk of a catastrophic failure - and lots of area for solar cells that can help power the relay.
You have to design a special ship, normal airships fly relatively low and their useful load drops off quite rapidly with altitude. You have to think about building BIG for quite a small payload. Then consider things like reliability, redundancy and UV light eating away at the envelope. But it should be doable.
A British company, the Advanced Technology Group is prototyping just such a relay. It's called StratSat and the prototype could fly in the next year or two.
Best wishes,
Mike.