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Cargo airships could be big

elidourado.com

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Re: Cargo airships could be big

#121

Post by waynenilsen »

cameronh90 wrote: post #118

As the article says at the end, a key technology here is automation. Lots of cargo isn't time sensitive, but paying a load of crew to take shifts sailing it slowly over the Pacific will kill the economic viability. Additionally, making it unmanned gets rid of a lot of the safety concerns, especially if you're going to use hydrogen and run them primarily over water. Still, hard to see the advantages compared to contai…

It seems about 2x faster plus overland capabilities should be great for some use cases that currently depend on canals.

Re: Cargo airships could be big

#122

Post by VBprogrammer »

rootusrootus wrote: post #111
nradov wrote: post #99

Earlier quoted context omitted.

I guess the last time was in 2013. Asiana Airlines Flight 214, a Boeing 777 jumbo jet, crashed at SFO with only 3 fatalities. Those are tough airplanes and low-speed crashes are often survivable if passengers can evacuate before the inevitable fire spreads. https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_214?wpr... It was kind of freaky seeing the burned-out wreck sitting next to the runway when I flew out of SF…

I was going to say that the 777 isn't a jumbo, but it looks like they're now calling it a 'mini jumbo'. Feelings of inadequacy, I guess, compared to the 747.

Meh, terms like this are pointless. Completely arbitrary where you put them.

It's probably more sensible to use terms like wide body, implying 2 aisles.

Re: Cargo airships could be big

#123

Post by coryrc »

kortilla wrote: post #100
credit_guy wrote: post #77

Earlier quoted context omitted.

There's actually no need for hydrogen. Helium would do just fine. From the blog post, filling the hypothetical airship with helium would cost $8 MM, while filling it with hydrogen would cost only $100k. Sounds like a no brainer. But, the overall cost of the airship would be at $100 MM. Hydrogen would result in a less than 10% cost reduction. Now, the FAA approved unleaded jet fuel in 2022. Yes, that's how conservativ…

The FAA approved modifications to piston engines to use unleaded avgas. Jet fuel doesn’t have lead. Also, this isn’t about the FAA just being slow for no reason. Switching from leaded to unleaded without the engine modifications was not safe for the piston aircraft that need it. https://en.wikipedia.org/wiki/Jet_fuel https://en.wikipedia.org/wiki/Avgas

It's not safe for us to be breathing. But that doesn't matter to cheapskate rich private plane owners or their regulatory-captured FAA.

Re: Cargo airships could be big

#124

Post by SuoDuanDao »

echelon wrote: post #33
splitrocket wrote: post #12

This, my friends, is why we should colonize the upper atmosphere of Venus, where you could chill outside with only a respirator, rather than the inhospitable, irradiated, mangnetosphere free mars. https://en.wikipedia.org/wiki/High_Altitude_Venus_Operationa... https://spectrum.ieee.org/nasa-study-proposes-airships-cloud...

I've always felt people with these ideas are doing pie in the sky thinking and missing the other trends that would beat this concept out. Humans aren't suited for these environments. We evolved to fit this planet. These gasses, radiation levels, terrestrial foods, etc. The economics of going to Mars, Venus, etc. are iffy, and humans probably won't enjoy being there. It's McMurdo times about 1000. Getting back is hard…

colonizing Venus with extremophiles that currently live in Terran ocean vents might be a good humanitarian (vivarian?) project. Life finds a way and all that, it'd be neat to offset the current great extinction with a new cambrian explosion on our sister planet.

Re: Cargo airships could be big

#125

Post by sitkack »

The article completely omits trains. That is glaring.

I had this steampunk like plan when I was in college to have huge hydrogen cargo airships pulled by trains to haul large bulk items (fully assembled houses, building parts, large trees, fully assembled combines, etc). A literal skytrain.

Some new lines would have to be created a way to handle going through tunnels etc. I think now I would have a drone be able to connect and unconnect the tether and the airship would be able to be autonomous for period of time and reconnect. Or a small track could be run just to connect the small tug needed to pull the airship.

Re: Cargo airships could be big

#126

Post by SuoDuanDao »

credit_guy wrote: post #115

Great analysis. A few random thoughts 1. The dreaded helium leakage. It might not be a problem at all. Think of a party balloon of the foil type. It stays afloat for weeks. And it has positive pressure. A neutral pressure one would leak much less. But maybe not to zero. Ok, now use a double layer. Just like there are double hull submarines, this would be a double foil balloon. The distance between the outer foil and…

would batteries work for fuel in an airship? I know the battery bank is a structural element in Tesla cars, seems like that could be done with airships as well (it'd increase the price precipitously of course)

Re: Cargo airships could be big

#127

Post by LarryMullins »

jodrellblank wrote: post #66

I'd like to draw your attention to " killing 35 of the 97 people on board in the inferno. " The Hindenburg had 7 million cubic feet of Hydrogen gas. It was the biggest aircraft disaster of its time. It had such rudimentary technology that the cockpit looked more like a sailing ship than an aircraft[1]. Despite that, well over half the passengers jumped out the windows[2], ran away and survived with few or no injuries…

Everybody always focuses on the Hindenburg, but it's not as though helium airships were much safer. In some scenarios they were marginally safer, but the deadliest airship disaster of them all was the USS Akron, a helium airship. 73 dead and 3 survivors, vs the Hindenburg's 36 dead and 62 survivors.

As for marginally safer: There were some cases of helium airships breaking up due to weather and people surviving the ride to the ground on still somewhat buoyant sections of the destroyed airship, whereas that was less likely with hydrogen airships because the wrecks would also burn. Compare the crash of the USS Shenandoah to the British R101; both were destroyed by bad weather but R101 had far fewer survivors because the wreck burned. But even with helium, airships are still very fragile and dangerous. Using helium isn't truly a panacea to the hazards of airships.

Re: Cargo airships could be big

#128

Post by moffkalast »

jodrellblank wrote: post #90
credit_guy wrote: post #77

Earlier quoted context omitted.

There's actually no need for hydrogen. Helium would do just fine. From the blog post, filling the hypothetical airship with helium would cost $8 MM, while filling it with hydrogen would cost only $100k. Sounds like a no brainer. But, the overall cost of the airship would be at $100 MM. Hydrogen would result in a less than 10% cost reduction. Now, the FAA approved unleaded jet fuel in 2022. Yes, that's how conservativ…

Helium is a non-renewable resource drilled out of the ground, of which there is a global 'crisis' shortage[1]. Hydrogen is easy to make in vast quantities and cheaper. But more importantly, while they have similar lift capacities on paper (Helium ~90% of Hydrogen), in practice they don't - https://www.airships.net/helium-hydrogen-airships/ has an explanation and calculations. Hydrogen lift airships set off fully infl…

Yeah hydrogen sounds like it could even be safer given that you get a larger buoyancy buffer to fight downdrafts? It's a real public misconception that it just explodes from all those oxyhydrogen experiments at chemistry class, but pure hydrogen such as in airships just slowly burns, much like any other fuel we fill our planes with.

The main problem is still that you need to contain a large volume, which will inevitably get pushed around by wind more than you can compensate for.

Re: Cargo airships could be big

#129

Post by sitkack »

btilly wrote: post #69
black6 wrote: post #61

Earlier quoted context omitted.

John Clark goes into detail in his book Ignition! about why smaller, lighter exhaust molecules are much better than larger and heavier ones.

John Clark also was the one who proposed adding mercury. It was a joke, that the military types didn't realize was a joke. Read https://library.sciencemadness.org/library/books/ignition.pd... pages 193-196 in the PDF for the full story.

One has to be really really careful when cracking these kinds of jokes, one really has to weigh the downside of it being taken seriously.

I'll still do it, on an ephemeral medium, and then spoil it seconds later. That is only way it can be delivered.

Re: Cargo airships could be big

#130

Post by aae42 »

triceratops wrote: post #120
jodrellblank wrote: post #90

Earlier quoted context omitted.

Helium is a non-renewable resource drilled out of the ground, of which there is a global 'crisis' shortage[1]. Hydrogen is easy to make in vast quantities and cheaper. But more importantly, while they have similar lift capacities on paper (Helium ~90% of Hydrogen), in practice they don't - https://www.airships.net/helium-hydrogen-airships/ has an explanation and calculations. Hydrogen lift airships set off fully infl…

If fusion power takes off, could you produce helium as a by-product?

if we figured out fusion, it would alter the economics of all of this

why not fusion powered ships/trains/airplanes

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