underground but not a fossil

[redpoint5]

Yes, Make Airships Great Again.

[Logic]

Originally Posted by freebeard

Use it for hydrostatic lift and eliminate microplastic pollution from tires?

IIRC there's actually a paper on that and using prevailing winds.

I don't recall what they had to say about the fact that your blimp is slowly deflating, or how to get it back again.

Ah!
https://www.sciencedirect.com/scienc...6031992306144X

[freebeard]

Isn't 0.25 bar a vacuum?

The ideal altitudes to transport hydrogen with balloons are 10 km or lower, and hydrogen pressures in the balloon vary from 0.25 to 1 bar.

I'm in favor.

A prolate spheroid tensegrity shell, for a rigid airship, with a hydrogen bladder suspended inside. The hydrogen would be hot at ~1 bar, and the intervening space would have pure steam. It has lift approximating helium's but modulating the heat would give vertical control authority.

The steam would also maintain the temperature of the hydrgen (in it's graphene bladder).