231–240 of 385 posts
Try off-loading containers when you're "ship" turns 90 degrees in < 30 minutes because a breeze came up.
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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An extreme example. One extraordinary event is not very good evidence. The safety record of the Zepplin company in Germany is very impressive They had many failures, no fatalities. Until the Hindenburg
The USS Akron, USS Shenandoah, and USS Macon all failed due to bad weather. That's 3 of the US's 4 operational airships. (Another airship was constructed for the US, but was destroyed by poor handling before it was delivered to the US.) Of the British experience with airships, R101 outright failed due to bad weather, and three more were scrapped after suffering accidents during bad weather, out of a total of 16 compl…
So long as they work "more" days of the year it's a better solution. Weather doesn't really sneak up on us anymore.
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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 "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…
Don’t stop there. Charged particles in the solar wind is mostly alpha and Beta particles. 33feet / 2.5 should stop what 99.9999% ish of them? 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 a…
Charged particles from the Sun (SEPs) aren't what determine the design envelope for radiation shielding. Your overall dose will almost entirely come from galactic cosmic radiation (GCR) at much higher energy levels, which is significantly harder to shield against.
Those particles are what ultimately determine your shielding thickness requirements. That's true whether you're on Venus, or Mars, or a space colony.
Germany's cargo airship project is now an indoor waterpark located in Brandenburg (close to Berlin) https://en.wikipedia.org/wiki/Tropical_Islands_Resort (With rising energy costs, hopefully it can stay like this for a while)
Probably a very stupid question, but can someone help me understand the following: once you have airships that have a rigid shell, why isn't using a vacuum better than a lifting gas? Isn't the buoyant force simply the result of displacing some volume of air with something less dense? (i.e. any excess lifting force comes from the fact that the mass of the hydrogen or whatever is less than the mass of the displaced air…
- Build a pressure vessel to withstand the differential to the atmosphere
- Let the helium do the pushing from the inside but make the thing 14% bigger
I don't see how the vacuum ever wins.
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> Basically you make a large (like a square kilometer or more) rigid kite (see Alex G. Bell's cellular kites) Those were incredible ( https://www.scientificamerican.com/article/alexander-graham-... ), but it would surprise me if you could scale them up to a kilometer in size. Also, from that article: “Aggregated rectangles increased kite weight faster than they expanded wing surface area. Tetrahedrons kept the ratio…
> but it would surprise me if you could scale them up to a kilometer in size. It's like the intuitive argument that heavier objects fall at the same rate as lighter objects: throw two shoes off the roof, if you tie their shoelaces together will they fall faster? You start with N kites and connect them, each kite retains its airworthiness and connecting them doesn't change that. > nearly [constant] The ratio falls off…
If you do that, you have N wires between the kites and the ground.
Keeping them untangled may be a problem. Your best bet probably is tying them together and having only one thicker wire towards the ground.
Making sure each of those wires takes 1/Nth of the load from the wind definitely will be a problem, even in a perfectly stable uniform wind. If you can’t guarantee that, you’ll have to make the wires a bit stronger than for the individual kites.
If you think “we won’t need 1 wire for each small kite”, you’ll need to make the connections between the kites stronger. To see why, think of the similar problem of a plank over a ditch. If a 1m plank over a 80cm ditch just holds your weight, do you think a similar 25m plank over a 20m ditch will hold you, standing in the center of the plank? Do you think it will hold 25 persons along its length?
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Tourism, mining high value minerals for Earth, mining low value minerals for construction on Mars, manufacturing rocket fuel so that Mars can be the gas station for ships headed for the asteroid belt (enabling more high value mineral mining), low-gravity retirement communities for people with mobility issues who would be wheelchair-bound on Earth, real estate speculation, movies, sports, manufacturing space infrastru…
If I were living on Mars, I would absolutely not be willing to let the rare minerals get sent up into space then down to Earth. Learn to recycle, damn lazy Earthers.
There's no doubt they'll be big, but will they be practical, economically viable and successful?
> 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…
Heavy lift. Put hundreds of tons of house(s) from a house factory or skyscraper level(s) from a skyscraper factory on them, airlift them to the building site around the country.
Centralise most of the building work in one efficient scaled up factory, deliver an enormous buildings quickly piece by piece by air instead of slowly by having all the parts driven around windy roads and through closed city streets and assembled by a crews of people travelling to the building site and home every day.