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Cargo Airships Are Happening

(www.elidourado.com)
220 points elidourado | 2 comments | 14 Oct 24 16:31 UTC | HN request time: 0s | source
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xnyan ◴[15 Oct 24 00:04 UTC] No.41843568[source]▶
The (biggest) problem that keeps airships from practical use is that they are huge sails. Big sails mean even small amounts of wind can be powerful forces acting on the airship. In the air a big push from the wind might be safely managed, but if you're near anything solid such as the ground, you can get smashed to bits.

To safely operate a suitably efficient (large) airship, we'd need both huge specialized docks with extremely strong mooring structures to keep wind from smashing the airship into whatever is near it, and a system (such as a 3-axis propulsion system on the airship) that is capable of counteracting wind force acting on the airship when it's near the ground or other solid objects and not docked.

Despite the many attractive advantages of airships, there's yet been anything like a good solution to this problem. There are other challenges too (what do you do when you drop off your cargo and the airship wants to shoot up into the air? Vent gas? Rapidly compress your gas?), this is just the biggest.

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0xCMP ◴[15 Oct 24 03:33 UTC] No.41844653[source]▶
I think they're aware of all these problems because they do mention almost everything you said in the linked post thinking through the idea: https://www.elidourado.com/p/cargo-airships

Obviously that was simply a post thinking through everything hypothetically and I didn't read anything that seemed like they actually had the best solution, but at least they seem to be aware of the challenges to landing and off-loading cargo efficiently.

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ben-schaaf ◴[15 Oct 24 05:47 UTC] No.41845304[source]▶
Reading that article I see no proposed solutions to this sail problem. They mention wind as an issue for delivery times but not safety. There's also no acknowledgement that the "scaling law" that makes building huge airships lucrative also makes these problems worse.
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wang_li ◴[15 Oct 24 14:41 UTC] No.41849113[source]▶
You're failing to see the secret that is exposed by the fact that their Chief Engineer comes from hyperloop. They're going to dig tunnels connecting all their destinations and run the airships underground in a vacuum sealed network. No atmospheric drag at all! Bingo!
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withinboredom ◴[15 Oct 24 15:29 UTC] No.41849609[source]▶
How can you call yourself an engineer and work on the hyperloop. Literally only takes about 30s of thought to realize it is an impossible idea.
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dr_dshiv ◴[15 Oct 24 16:21 UTC] No.41850173[source]▶
Please reveal the impossibility of the idea?
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withinboredom ◴[15 Oct 24 20:48 UTC] No.41852943[source]▶
Sure.

If you put it above ground, you are a few short bullets from killing everyone in the loop. Hitting a wall of air in a vacuum at hundreds of miles per hour is going to be like hitting a brick wall. Ask any reentering spacecraft.

The same problem exists underground, the weakest points being the stations themselves which can be bombed.

A failure in the system itself (even just a power outage or malfunctioning equipment) would mean people suffocate inside after a matter of minutes.

So, sure, it is possible to create it, but it is impossible to make any sort of safety guarantees. In other words, literally any other mode of transport would be safer, including a hydrogen-filled dirigible.

So, sure, the concept itself might be possible, but an engineer doesn't concern themselves with possible. That is for scientists. An engineer considers what is realistic AND possible, because that is an engineer’s job: to make the possible real. This cannot be real; literally no regulator would ever sign off on it.

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1. milo256 ◴[17 Oct 24 01:08 UTC] No.41865473[source]▶
Huh? In what world is a hyperloop going maybe 700mph comparable to a spacecraft reentering from orbit at 17,000mph? Also, maybe there's something I'm missing but spacecraft can and do renter from orbit intact, thus proving that this problem is solvable even when the forces at play are orders of magnitude greater. Apply your safety argument to passenger airliners or even ordinary trains and you'll see that they are also "impossible to make safety guarantees" for.
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2. withinboredom ◴[18 Oct 24 19:13 UTC] No.41882518[source]▶
> In what world is a hyperloop going maybe 700mph comparable to a spacecraft reentering from orbit at 17,000mph?

In that case, the air can just "go around" the space craft. Try pushing down a syringe with the end capped. Bet you can't do it. Now imagine that at 700 mph; you will get a lot of heat and destruction. No heat shielding will save you.

> Apply your safety argument to passenger airliners or even ordinary trains and you'll see that they are also "impossible to make safety guarantees" for.

See sibling comment.