181–190 of 385 posts
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if we figured out fusion, it would alter the economics of all of this why not fusion powered ships/trains/airplanes
> why not fusion powered ships/trains/airplanes[?] What could possibly go wrong?
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> There's no doubt they'll be big, but will they be practical, economically viable and successful? Frankly no. Its like every few years people remember about airships and suddenly start shouting how its the answer to the world's problems. I mean, just search here on HN... 11 years ago there was "Blimpocracy - Is the airship the transportation system of the future?"[1] .... now here we are 11 years later, and, well, y…
What about places with limited rail/roads like Alaska and Kazakhstan?
What about them ?
If there's no cargo facility there already, then nobody's going to suddenly turn up and build an airshipport (or whatever you want to call it).
The way modern day logistics works is like an inverse pyramid, you fly/ship/train in bulk somewhere, and then you go smaller and smaller scale to the remote/rural areas ... right down to a man on a bicycle or whatever.
Cargo airships, IF they ever happen, are not going to change the fundamental way modern logistics works. Basic economies of supply and demand. Sending the man on the bicycle will always be the cheapest and most sensible option for remote areas where only a handful of people live, especially if they live many miles from each other (e.g. rural farming).
If something doesn't exist, especially when it's something that has existed in the past but no longer does, there's usually a good reason for it. It's not a natural law, but it's a good rule of thumb to use to initially question and defend a "groundbreaking" idea. A quick search online tells me that ocean freight is about $1.3/lbs and air freight is about $5.3/lbs. Since we already know that "airships" would likely n…
They do have advantages over ocean freight (not everyone lives near a major sea port, or any sea port.) I'm not sure if your price includes road transport, or rail, depending on where you are. Sea is obviously a Lao quite slow.
Air freight is expensive, and also somewhat limited airports. In some parts of the world there are lots of those, but most freight travels to a major centre, then trucks etc.
I see airships as more of a "trucking" compeditor. Theoretically it can load and unload with minimal ground infrastructure. And it can go places trucks can't go.
Yet with all of that the killer problem (literally) seems to be weather. It's hard to see how that problem is reliably solved.
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Even with the Akron, we're focusing on the first disaster and not on the improvements or possible improvements since then. 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 repetiti…
> 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." Yeah, but notably they hadn't solved the problem of wind tearing airships apart. In the case of Macon they landed gently and in warm water, and lifejackets certainly helped. But a soft landing is b…
> What we observe under these conditions is that, domestically, most of both the tonnage and value of cargo is transported via truck. Trucks are neither the fastest nor the cheapest mode of transport, but they provide a great value proposition—you get your stuff in a few days for much cheaper than air freight. I feel like this is a bit naive. The true competitor to trucking is rail. But trucking is preferred because…
I concede I might be totally wrong here, but the issue with rail seems to be profitability. I live in (moved to) Europe, and the railways are far more developed than in the US. But as far as I know, they all have to be heavily subsidized by the governments to even function. None of them operate with a true profit. Here in Germany, 2.2% of the latest federal budget is to support the railways. This is despite the railw…
Trucks pay most of infrastructure costs through fuel taxes and registration fees.
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…
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> why not fusion powered ships/trains/airplanes[?] What could possibly go wrong?
We already have fission powered ships and submarines.
and https://en.wikipedia.org/wiki/Lockheed_CL-1201
And dreams of fission trains: https://twsmedia.co.uk/2020/05/09/atomic-trains/
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1 ATM of air is the same amount of material as 33 feet of water which provides a great deal of protection from charged particles. I doubt enough charged particles can penetrate to the surface that it’s a meaningful issue. I’ve seen many books etc suggest the earths magnetic field is required, but I haven’t found direct evidence for it doing anything beyond protecting the ozone layer.
>1 ATM of air is the same amount of material as 33 feet of water which provides a great deal of protection "Amount of material" isn't what's relevant. It's closer to "number of atomic nuclei." A certain mass of air is less shielding then the same mass of water. By number density, air is mostly nitrogen atoms, whereas water is mostly hydrogen atoms. Overall this means that per kilogram, water contains 2.4x as many ato…
https://sciencedemonstrations.fas.harvard.edu/presentations/...
Absorbing materials and their alpha particle penetration depths.
5.5 MeV alphas: AIR(STP) 3.7 cm
2.3 MeV Beta: air 8.8 m
Solar wind is even less energetic.
Edit: “Auroral emissions typically occur at altitudes of about 100 km (60 miles); however, they may occur anywhere between 80 and 250 km (about 50 to 155 miles) above Earth's surface.” it really doesn’t take much atmosphere to stop it.