[lifeisstillgood]

I am trying to avoid being negative here but lifting 250 tonnes in remote / difficult areas is a serious challenge.

The lift is not so much the problem (although that's a big balloon) - fighting wind sheer will require stupendous amounts of power. Especially as wind is pressing not just at that cargo but at the balloon itself. And anywhere that's remote / inaccessible almost always comes with lots of wind.

Hmm, actually lift might be a problem ...

So to get 250 000 kg off the ground takes a volume of helium balloon (if the below site is right) of 250,000m3 (it seems to be fairly linear)

(this seems intuitive - air "weighs" about 1.2kg /m3 sea level, so a vacuum of 1m3 could lift 1.2kg. )

that is 100mx100mx25m ! that's the inner part of any athletic stadium. That's insane surely?

https://www.engineeringtoolbox.com/hot-air-balloon-lifting-f...

[smoyer]

I came to admit I can't imagine how the small solar power "field" shown on top of the balloon could possible push that shape through the air - either at a reasonable speed for transport or to counteract wind. If lift isn't a problem as you pointed out above, what might work is a tethered version that basically replaced the need for a tower crane. You could develop a tethered, active mooring that was much like the four-point active anchor system the navy uses to accurately maintain position during submarine rescue.

[CraigJPerry]

>> that is 100mx100mx25m

That’s huge!

I wondered how big was the hindenberg, wiki claims 245m long and 41m wide, and 41m tall (excl. cabin). Only 200k litres of gas capacity. 232k tonnes lift.

[ixfo]

So it is huge, but well within historic capabilities - and materials science has come a long way since then. I'm quietly hopeful for this.

[masklinn]

> So it is huge, but well within historic capabilities - and materials science has come a long way since then. I'm quietly hopeful for this.

The problem is not building the thing (though it is one problem), it's that if you're using this as a crane you're moving an entire baseball field with a decimeter if not centimeter-scale precision.

[ZeroGravitas]

The problem seems to scale with the weight carried.

I have no intuitive feel for how heavy 250 tonnes is, but even if current crane tech can move that weight with centimeter precision, they're explicitly marketing this for tasks where the current tech has issues with access, which implies they don't think it competes directly with traditional cranes on their own territory, but does work well enough in specific circumstances to be an option.

Maybe its a bad idea overall, or unrelated business model issues render it a dead-end, but beating the current product in every concievable metric in every concievable use case is not necesssry for a product to be a success.

[ClumsyPilot]

I think the difficulty is not that its a huge airship, its the precision required to use it as a crane.

[CraigJPerry]

That's an area i'd be quietly hopeful in. Assuming propulsion motors are available which are both:

  a) powerful enough to defend against wind acting against such a huge object
  b) responsive enough to change their thrust vector (power & direction) such
     that the associated PID loop can operate within some reasonable set point
     boundary

Then there are already open source hardware and software solutions available for this - i'm not proposing someone slaps a pixhawk 4 on a huge airship and gets a few mates over to help tune the PIDs in Ardupilot - i mean that the know-how is there. Translating that into a product that would be suitable for controlling such an aircraft would be do-able. Certification costs and expensive hardware suitable to run it all on are a different matter.

I guess this is a long way to say i don't think it'd be easy or cheap, but i don't think they'd have to make a break through innovation to make it possible.

[ClumsyPilot]

I think this is fundamentally impossible, win loads are powerfull enough to ouright warp and destroy giant ground based cranes like they were tissue paper if the operator makes a mistake, like lifting oart of a stadium roof in high wind. there are scary videos all over youtube. Those things and made of hige steel girders.

This is going to be a light, fragile airframe with much bigger 'sail' in the form of the airship - its the size of a stadium.

Nothing short of a rocket engine will be able to keep it in place.

[CraigJPerry]

The skin of a Boeing 747 is about 2mm thick. We’ve been hurling them at 600mph through storms for half a century at this point.

I don’t know for sure but i suspect the airframe of this concept is within reach of current tech.

[lifeisstillgood]

So that's 411k m3 with only half that as gas capacity ! Interesting.

But back-of-the-envelope lighter than air is just hard. It's certainly possible to see this working in niche areas, but boy, it's a tough sell compared to "get a giant Sikorsky"

[masklinn]

> So that's 411k m3 with only half that as gas capacity ! Interesting.

Not sure how you reached 411, 245 x 41 would be 323k for a straight cylinder, which the hindenburg was nowhere near[0]. And the envelope was larger than the useful gas volume owing to the internal scaffolding, and the internal volume being subdivided into 16 cells separated by structural rings[1].

And the 232t useful lift was pure lift, before taking in account the 215t of the airship itself (at basic empty weight). The useful lift (payload) was 40 crew, 50 passengers, their luggage, and 10t cargo.

[0] https://3iz4pu1r2cxqxc3i63gnhpmh-wpengine.netdna-ssl.com/wp-...

[1] https://3iz4pu1r2cxqxc3i63gnhpmh-wpengine.netdna-ssl.com/wp-...

[lifeisstillgood]

Thank you.

I got to 411k by 245x41x41 (figures in GP). Yes that's not a cylinder but I am just doing very rough maths.

I did not think about the useful lift - so while the Hindenburg is a 100 years old, a lift of 232k kg was competing with a empty weight of 215. incredible - and thanks for the links

It still seems back of the envelope that lighter than air lift is just not generally useful

[cycomanic]

It's somewhat interesting that people are saying this is unrealistic because of the possible 250t maximum lift version. And then people bring up helicopters, that just shows how little idea people have about what insane amount 250t is. The strongest helicopter is the Mi-26 with a lifting capacity of 20t (the sikorsky has something like 12t AFAIK) so that's an order of magnitude off. It is safe to say that building a helicopter with that lift is very likly out of our engineering capability.