321–330 of 385 posts
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> I don't see how the vacuum ever wins. 3 ways. - Vacuums aren't combustible. - Vacuums can be created without sourcing a gas. - Vacuums allow you adjust buoyancy without requiring you to carry extra gases. The major downside of a vacuum is finding something ridged enough, light enough, and cheap enough to maintain a vacuum.
Helium isn't combustible either.
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We already have fission powered ships and submarines.
We almost had fission powered airplanes and airships: https://en.wikipedia.org/wiki/Nuclear-powered_aircraft and https://en.wikipedia.org/wiki/Lockheed_CL-1201 And dreams of fission trains: https://twsmedia.co.uk/2020/05/09/atomic-trains/
The military are mad. Mad and bad. It is in the job description.
We would all be better off if none of them (the military) existed
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> Hydrogen is also dangerous, and there does appear to be a double standard here. I don't have beef with hydrogen, but I suspect it's a lot easier to secure fuel in a liquid state versus a gaseous state. Putting a lot of hydrogen in a relatively small steel container for use in an engine seems quite a lot safer than putting it in a big bubble and then dangling people from it. But I am not an aerospace engineer, could…
I too am not an aerospace engineer, but venting hydrogen after touch down seems easy enough. After all if you open the cells the gas just goes away. By contrast a broken fuel tank leads to liquids spilling on the ground, which seems like fun. That all said, liquids don't explode, gasses do. So if you were unlucky and the hydrogen exploded then life would get very exciting very quickly.
There may be a technical definition of explosion that says an exploding tank of fuel is not "exploding". Do you care?
A ball of fire is an horrific thing
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I know some of the Canadian provincial governments were looking at using airships to provide a means of supplying some of the more remote northern towns - because of weather/terrain conditions, you can't build a rail head that far north, and the roads aren't reliable, so light cargo planes are the only reliable means of getting goods around. Airships, even of the good year variety, would be far cheaper for the weight…
You wrote: you can't build a rail head that far north The Trans-Siberian Rail can do it... but Canada cannot?
So it's not that you _can't_, but it's a PITA, and it's very far from value for money for so few people.
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You wrote: you can't build a rail head that far north The Trans-Siberian Rail can do it... but Canada cannot?
Virtually all of the Trans-Siberian railroad (except for the Amur-Yakutsk spur) is below the Canadian North. There are railways to northern places in Russia (such as Murmansk), but Murmansk has 200k people (down from 500k in 1989), where the largest settlement in the Canadian North is Yellowknife, with 10% that number. So it's not that you _can't_, but it's a PITA, and it's very far from value for money for so few pe…
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It depends on the plane, but both your point and the parent point are correct. Piston engines run on high octane gasoline (Avgas) . This is the stuff that powered planes up to, and just past, ww2. Today it's still used in planes from that era, and some smaller general aviation planes. Jet fuel (jet a1) is basically paraffin. All turbine engines (think "jets", but also turbofan etc) run on this. It's a lot less flamma…
> Hydrogen is also dangerous, and there does appear to be a double standard here. I don't have beef with hydrogen, but I suspect it's a lot easier to secure fuel in a liquid state versus a gaseous state. Putting a lot of hydrogen in a relatively small steel container for use in an engine seems quite a lot safer than putting it in a big bubble and then dangling people from it. But I am not an aerospace engineer, could…
Here's what happened 10 years ago: https://www.youtube.com/watch?v=FG1LGKieTxY
I understand that it's just reckless driving. And had this been a gasoline tank, it may have burned as well, but at least no cylinders would have flown around.
Though, its still seems safer than pressurized methane. 300 bar make cylinders explode, probably from material fatigue. It doesn't burn, because decompression makes it super cold, but still, the car is ripped apart. https://www.google.com/search?q=%D0%B2%D0%B7%D1%80%D1%8B%D0%...
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Or a single tracer bullet, if it's filled with hydrogen.
Airships were routinely used and shot at in WWI, but very few were lost due to being hit. If you think about it, it makes sense: they are massive, so the loss of pressure from a bullet hole isn't a real concern. And while the right hydrogen-oxygen mix is explosive, hydrogen needs oxygen to even burn. But there isn't any oxygen in the tank bladder. The escaping hydrogen can burn as it mixes with air if it finds an ign…
While adding a layer of solar to strengthen the construction seems a good plan there is also fantastic wind up there. One might use turbines or even sails to propel the craft.
If you make it truly large you won't need a gas. Can just use a hard vacuum... It's going to have to be big tho. At least a few km.
The airship renaissance is the fusion of transportation world. It's always ten years away. Seriously, I've been hearing about the great promise of modern airships for twenty years. Where are they? Are there any airships operating commercially now outside of niche applications?
The project I am pitching currently, which has a good chunk of financing secured, envisages passenger operations in seven years. The piece is almost spooky in its similarity to the piece I circulated to investors a month ago. We aren’t, however, going after the cargo market. Will it get off the ground? Who knows. But if you see kilometre-scale airships emerging from the backwaters of Europe where subsidies abound and…