151–160 of 385 posts
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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
What could possibly go wrong?
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airships have multiple cells though, a single rip wouldn't doom the entire thing
But what caused the airship to rip? If it was wind, then you now have that same destructive wind ripping through the inside of your airship through the hole.
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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…
Lift gas is a consumable. You have to vent it to descend in many cases, and that’s ignoring the inevitable leaks and diffusion.
Helium blimps compression the gas to lower buoyancy
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what are we going to do from mars
Everywhere but Earth is really inhospitable, but if it were up to me, I'd pick the Moon first, then Mars, then some asteroids, then way down the list — after we've got space industry sufficient to make planet-sized mirrors — then I'd pick the planet where the surface-level condensation is lead vapour in an acid pressure cooker.
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 c…
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 r…
Akron crashed into the Atlantic in April. "Most casualties had been caused by drowning and hypothermia, since the crew had not been issued life jackets, and there had not been time to deploy the single life raft."
Followed by: "Macon and other airships received life jackets to avert a repetition of this tragedy. When Macon was damaged in a storm in 1935 and subsequently sank after landing in the sea, 70 of the 72 crew were saved."
The R101 was a stupid tragedy - they designed and built it, then extended it, then launched the first flight without sufficient testing to learn how the extension had gone and how it handled after, in poor weather conditions, because the launch date had been decided by politicians as a piece of propaganda about reaching the far corners of the British Empire by airship.
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If US, China and Taiwan situation escalates and US imposes a naval blockade, this can be used to effectively circumvent it. Perhaps China should invest in this.
Massive airships flying 90/km an hours are LESS susceptible to blockades than cargo ships? I think I'll need a little more explanation than that. Seems like a shoulder-mounted rocket launcher would be more than enough to bring one down.
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…
> 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 the inner foil would be only 1cm or…
It will not. The outgassing is proportional with the difference in partial pressure. On the outer foil the difference in partial pressure is 1 atmosphere (only helium inside, no helium outside). In time helium will leak out. Air will probably not leak in, by you can add it, to maintain equal pressure. The point is that you won't add a lot. Let's say that in one year 5% of the helium gets replaced.
That means the difference in partial pressure on the inner foil is at most 0.05 atmospheres. The leakage will be much lower. Most likely you would not need to refill the helium inside the inner foil more than once during the lifetime of the airship.
I feel like this is a bit naive. The true competitor to trucking is rail. But trucking is preferred because it's point-to-point and you don't have to deal with intermodal connections. Airships would have these exact same problems (unless you invented some way to build routes and drop off containers at specific addresses - but then you are back to it being slow again!).
So the only real market would be replacing container ships with something slightly more expensive but faster. But even using his own math - a fleet of 25,000 airships each with only a 500 ton capacity, and each being twice as big as the biggest airplane ever built - seems like a nightmare. All to only capture half of the global shipping market!