[doikor]

Just fly it close to the ground and the only controlled airspace is near airports (and some big cities, military stuff, etc). Should not be that hard to stay out of those for the most part if you are transporting stuff like windmill parts to the middle of nowhere.

[lstodd]

If you fly low how do you deice the thing while avoiding terrain? Most of the crashes were due to flying into the terrain in adverse weather conditions after all.

[doikor]

Flying low does not mean "scraping trees" but for example Glass G airspace (uncontrolled basically) is everything under 1200' not near airports etc. For a lighter than air craft 1000 feet off the ground is quite a big margin of error actually.

And I doubt one would be flying something like this in bad weather anyway. One would just wait for the next weather window.

And one could easily take the ship into 4000' or something like that and still have minimal amount of other aircraft around once outside of airports (proper commercial jets fly at 40k feet or so).

[lstodd]

> 1000 feet off the ground is quite a big margin of error actually.

Actually, no. It can't maneuver fast enough, it can't gain altitude fast enough. A downdraft or a squall and it's going into a hill or a tree from 1000ft in no time.

Only good thing about lighter-that-air is that when they crash, they tend to crash slowly. Otherwise completely useless.