[H8crilA]

This will be a pain in the ass to manage in controlled airspace because it's so much slower than anything else. But I guess it would also use different flight levels, so maybe not a problem at all.

I wonder how does the fuel usage compare to a plane, that's the real measure of green-ness.

[krisoft]

I think comparing it to a plane is misplaced. They call it a crane. Presumably the load and the craft arrives on a truck and you use it to hoist the load up the last few maybe hundreds of meter max. Do i read that wrong?

Edit: yes! I was reading that wrong. To quote the relevant part: “SkyLifters fly from job to job, so they can do work in locations that would be challenging for land cranes.”

[masklinn]

> Presumably the load and the craft arrives on a truck

Nah they're absolutely gigantic and usually semi-rigid (especially if you have solar panels on top).

SkyLifter seems very cagey about the purported crane's dimensions (couldn't find anything on the subject), but the Airlander 10 (which I understand only lifts 14t) is 90 x 43 x 26... meters.

IIRC the rule of thumb is that you need 1m3 of helium to lift 1kg, to lift just a 250t payload you thus need 250000m3 of helium.

According to skylifter's "design" page the lenticular envelope has a height of 1/4th the diameter (3 units wide, 0.75 units deep). For a cylinder that's 108m wide and 27m high, so taking in account the lenticular shape we might be closer to 120m/30m (400ft wide by 100ft high). That's the size of a baseball field, and 14 stories high.

And that's only taking the payload in account, not the solar panels, not the cabin, not the engines, ...

[Already__Taken]

If you rent a crane though you're also paying for the crew to drive the thing to you. This really has a chance of just auto-piloting over to the job to be then be run by an operator.

[masklinn]

You'll definitely be renting the crew. The skylifter website specifically mentions the one crew. And per my calculations the thing is the size of a cricket or baseball field, there is no way it'll be flying itself.

[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.