[lazyjones]

> 250 tonnes is A LOT to lift. Look how big a hot air balloon needs to be to lift a few passengers in a basket.

Does it scale? Can you strap 10 of those things together (perhaps using some sort of scaffolding) to lift 10x the weight?

[masklinn]

In the sense that lift is linear by volume yes, but the driving complexity I expect would increase superlinearly.

If you're strapping 10 things together, you're now dealing with a much less rigid structure, the straps/scaffolding are significant points of failure, and the attachment points don't scale the same way so you have to add an even more complex (and tangle-able) web of cabling for your payload.

[Toutouxc]

Yes, individual cells filled with lifting gas scale nicely (after all that's how rigid airships are made), but the main issue here is "big", not the actual arrangement or architecture. You need BIG to be able to lift HEAVY.