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Hyperloop Alpha [pdf]

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91–100 of 202 posts

Re: Hyperloop Alpha [pdf]

#91

Nice font. But looks good so far. EDIT: There's a bit of minimally technical details, but this is neither highly polished (public-perception-focused) nor highly technical (engineer-focused). Is it a good balance or would one of the extremes have been better?

It says right at the beginning that the first section is an overview while the second section is more technical...

So? It needed a section with more polish than the first section for not HN, and a more detailed technical section.

Re: Hyperloop Alpha [pdf]

#92

Strange PDF title -- "Falcon 9v1.1 - Reentry Nozzle Study" -- is there some design reuse or just document reuse?

I bet they titled it like that to hide it from prying eyes. That way even if you found the account where it was being stored, you would have no idea it related to hyperloop; and there were probably people looking for this sort of document.

Re: Hyperloop Alpha [pdf]

#93
post #55
post #17

The focus from people on bathrooms is puzzling to me. I've been on buses, without facilities, that go for hours without stopping. This is a 35 minute ride with restricted movement, if you greatly fear being able to hold it for that long, there are other, less efficient methods of transport to accommodate you.

If not using the bathroom for an hour is an issue you should see a doctor. Not only are there good treatments to alleviate this, but it may be an indication of a serious medical problem. Get it fixed then enjoy life including perhaps the Hyperloop.

I agree with the sentiment, but its part of the disadvantages of this transport. You cant travel with babies or little kids in them, and you certainly cant do it sick.

However its not such a big flaw, specially to warrant 63billion to alleviate.

Re: Hyperloop Alpha [pdf]

#94
post #11

It's interesting that the biggest line item in the costing is not the tube, nor the capsules, nor the vacuum pumps, nor the solar panels, nor the land, but the concrete pylons that support the tube - about two-fifths of the total. The pylons are planned to be 30m apart, making for about 25000 of them.

But that's the beauty of it! You can make those pylons anywhere, truck them in, and install them in whatever order you want. It's construction....that scales up almost effortlessly.

perhaps you can pour sections and truck those in, but there's no way in hell you're moving a precast that size on anything that doesn't float.

For scale, you know those 4' by 4' by 8' blocks of cement you see all over the place, used for erosion control and the like? They're called ecology blocks, they're about $20 each FOB the cement plant. You want them shipped? A lowboy can carry two or four at a time without exceeding load limits. When I looked into buying a couple hundred, having them shipped about sixteen miles, it was going to cost hundreds per block to truck it out plus renting a crane to unload/place them.

Those are tiny blocks with almost no rebar, no engineering, no preload, nothing.

Re: Hyperloop Alpha [pdf]

#95
post #56
post #42

Earlier quoted context omitted.

What will probably happen is that you get a transparent car and advertisements on the inside of the tube.

That fly past a metre from your face at 1,000 km/h!

"Have you seen the 200 foot long billboards in the country beyond town? Did you know that once billboards were only twenty feet long? But cars started rushing by so quickly they had to stretch the advertising out to make it last." -- Ray Bradbury, Fahrenheit 451

Re: Hyperloop Alpha [pdf]

#96
post #55

Earlier quoted context omitted.

If not using the bathroom for an hour is an issue you should see a doctor. Not only are there good treatments to alleviate this, but it may be an indication of a serious medical problem. Get it fixed then enjoy life including perhaps the Hyperloop.

I agree with the sentiment, but its part of the disadvantages of this transport. You cant travel with babies or little kids in them, and you certainly cant do it sick. However its not such a big flaw, specially to warrant 63billion to alleviate.

Nappies.

Re: Hyperloop Alpha [pdf]

#97
post #79

Earlier quoted context omitted.

But that's the beauty of it! You can make those pylons anywhere, truck them in, and install them in whatever order you want. It's construction....that scales up almost effortlessly.

I suppose that's true, though I don't know if that's a real difference compared to building other very long things that are the same all the way along, like roads and railways and the Great Wall of China. It's just fascinating to me that the most expensive thing (in aggregate) is also the "dumbest" part.

The most expensive thing in aggregate is the part which surely received the most attention when cost cutting. I think it makes perfect sense it's the dumbest part.

Re: Hyperloop Alpha [pdf]

#98
post #94

Earlier quoted context omitted.

But that's the beauty of it! You can make those pylons anywhere, truck them in, and install them in whatever order you want. It's construction....that scales up almost effortlessly.

perhaps you can pour sections and truck those in, but there's no way in hell you're moving a precast that size on anything that doesn't float. For scale, you know those 4' by 4' by 8' blocks of cement you see all over the place, used for erosion control and the like? They're called ecology blocks, they're about $20 each FOB the cement plant. You want them shipped? A lowboy can carry two or four at a time without exce…

Ecology blocks: http://www.tworiverssandandgravel.com/wp-content/uploads/201...

Re: Hyperloop Alpha [pdf]

#99
post #11

It's interesting that the biggest line item in the costing is not the tube, nor the capsules, nor the vacuum pumps, nor the solar panels, nor the land, but the concrete pylons that support the tube - about two-fifths of the total. The pylons are planned to be 30m apart, making for about 25000 of them.

They don't seem to break down the labour costs of building the tube/pylons very well. In my experience watching big government projects, that's where the massive overages start coming in.

It's easy to say that something will cost (eg.) $1bn if it's built in 2 years, but when most of that is labour and bureaucracy starts getting involved, the labour gets put on hold for a year or two whilst still getting paid. Suddenly the overall cost of the project has tripled without anything actually changing, except some bureaucrat sticking their oar in.

Maybe I'm just cynical, but the labour costs seem to be one of the least well defined aspects of this proposal. It's easy enough to make it look cost effective compared to existing rail projects when you don't factor that in.

Afterall do you really think that the HSV with two steel rails is costing $80bn+ because of the price of the components? Although I don't really know the specifics, I find it hard to believe that the rights of way cost that much either. It's usually down to contracting an entire company worth of engineers for 10-20 years that ramps up the costs.

Re: Hyperloop Alpha [pdf]

#100

Strange PDF title -- "Falcon 9v1.1 - Reentry Nozzle Study" -- is there some design reuse or just document reuse?

A funny mistake most likely, probably document reuse for basic layout. Download it again. It was just updated from "Nicholas Liggett" and "Falcon 9v1.1 - Reentry Nozzle Study" to "Elon Musk" and "Hyperloop Alpha"
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