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Hyperloop

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Re: Hyperloop

#261

Post by LekkoscPiwa »

geoffschmidt wrote: post #252
LekkoscPiwa wrote: post #206

Earlier quoted context omitted.

but why to ask California State for subsidy? Why not to build it using private funds? I'd imagine that if this is economically sound idea there must be potential investors lining up to have their share in the Project? The estimated cost is $7B. Now, Musk just needs to make a few calls to his friends at Google, Amazon, etc. Can't these guys just form a company together just to build it? Maybe I'm naive... or maybe Mus…

(1) CA is much better positioned to straighten out the land use issues. It needs to use the existing I-5 right of way, it needs to tunnel through some mountains, and it probably needs to eminent domain some additional bits of land for pylon bases where I-5 curves too sharply. No matter what, this is a project that has to pass the legislature in order to get built. (2) A CA-sponsored bond issue must be by far the lowe…

Can't (1) and (2) be solved by additional $1b to cover "cost" the Government might have? Just make it easier for them to move it through legislature, mountains, and such ;-)

Re: Hyperloop

#262

Post by spikels »

dragonwriter wrote: post #246
spikels wrote: post #216

Earlier quoted context omitted.

If the California high speed rail project is completed (or even makes progress) it will likely stifle any similar projects for decades. Competing against government projects is hard enough because the goverment has the incentive (from voters, contractors, workers, unions) to "succeed" regardless of costs and has access to vast resources thru taxation as well as control of the rules of the game (laws, regulation). Pro…

> If the California high speed rail project is completed (or even makes progress) it will likely stifle any similar projects for decades. Building railroads (road networks, etc.) over non-trivial spans of land is practically impossible without active government support. Even if California doesn't build HSR, private efforts without government involvement would be pretty much impossible.

Agreed ANY project will require government support. I just don't see many governments supporting competing projects. So if CA HSR gets built competing projects, such as Hyperloop, are unlikely to get the required government support. Make sense?

Re: Hyperloop

#263

Post by clarus »

outworlder wrote: post #195
macinjosh wrote: post #127

For all of you whose panties get wet at the sound of Elon Musk's name Hyperloop is essentially just Aérotrain in a tube: https://en.wikipedia.org/wiki/A%C3%A9rotrain This guy isn't really a genius, he's just rich.

Not really. There are similarities in the car's design, just as there are similarities among airplanes. Aérotrain is a magnetic levitation train, Hyperloop does not use magnetic levitation. Read the PDF.

Aérotrain is not magnetic, it uses air resistance too. Read the link, ahem.

Re: Hyperloop

#264

Post by delsarto »

dvmmh wrote: post #108
delsarto wrote: post #61

No toilet, and no way to get off, or even really stand up? I know some personal jets lack such facilities, but they're not exactly open to the public. At least on BART you can move away from the crazy...

No toilets on commuter buses either and people ride them 45minutes to 1+ hours everyday with no issues. You're stuck in the "long trip" "it's like a train" framework. It is neither.

The distance is just about what I commuted on a bus for many, many years, also with no facilities.

In peak hour it would probably be fine, when everyone is fairly sensible and not drunk. But after hours, I've had quite a few uncomfortable bus rides due to the various anti-social behaviours of fellow passengers. That was with the hand-brake of a driver who obviously isn't getting involved, but can avoid escalating behaviour by stopping the bus or calling authorities.

I have great faith in the technology! I just wish I had as much faith in the people riding inside it :)

Re: Hyperloop

#265

Post by sitharus »

marshray wrote: post #203
ciex wrote: post #153

Earlier quoted context omitted.

How do you get out of there in case of fire? If the doors open like that I don't think it would work while inside the tube wouldn't it?

Well, there's a low grade vacuum outside so you probably don't want to. It's a failure of the onboard steam tanks that scares me. ("The steam is stored onboard until reaching the station. Water and steam tanks are changed automatically at each stop") I don't want to think about what the result of that would look like for the cleanup crew. Eeeewww.

I really doubt the steam tank will be inside the pressurised volume. If they fail they would vent overboard. While an explosive failure would probably cause problems it wouldn't expose the passengers to high pressure steam.

The failure mode for composite overwrap pressure vessels is a slow leak, due to the overwrap containing the metal.

Re: Hyperloop

#266

Post by weeber »

outworlder wrote: post #195
macinjosh wrote: post #127

For all of you whose panties get wet at the sound of Elon Musk's name Hyperloop is essentially just Aérotrain in a tube: https://en.wikipedia.org/wiki/A%C3%A9rotrain This guy isn't really a genius, he's just rich.

Not really. There are similarities in the car's design, just as there are similarities among airplanes. Aérotrain is a magnetic levitation train, Hyperloop does not use magnetic levitation. Read the PDF.

Aérotrain uses air, like the hyperloop.

Re: Hyperloop

#267

Post by jessriedel »

flyt wrote: post #242
jessriedel wrote: post #235

OK, so he says it's much cheaper than high-speed rail mostly because pylons require taking much less land through eminent domain. Can anyone explain to me then why high speed rail can't be built on pylons?

Weight of the rolling stock.

"For those who don't know the lingo, "rolling stock" just means "all the vehicles on the train."

Does he say this explicitly? (Sorry if I missed it.) Why can't you make a train car just as light as these cars, and also skip the weight of the tube?

Re: Hyperloop

#268

Post by bsbechtel »

lmg643 wrote: post #180
aresant wrote: post #32

"In the case of the Hyperloop, Musk started focusing on public transportation after he grew disenchanted with the plans for California’s high-speed rail system." And who says that big government stifles entrepreneurial innovation? If ALL Musk does with the Hyperloop announcement is shed more light on the potential debacle that is to be our $70b+ high-speed rail in California, we owe him a debt of gratitude. PS - Dire…

Interesting point that big government provoked the advancement of the hyperloop idea - counterintuitive idea, and clearly yes. but any idea like this will need government cooperation. The real test of big government will be how they respond to the hyperloop. magic response: "of course we may be wrong, we'll look into this immediately." and then they decide to build it. likely answer: praise, perhaps even an evaluatio…

Um, pressure your representative to support this idea instead of a high-speed rail system?

Re: Hyperloop

#269

Post by MBCook »

Osmium wrote: post #199

Reading the entire PDF is highly recommended; it contains a surprising amount of answers already (including many to comments below). I think, if anything, safety aspects haven't been sufficiently explored in the pdf. I'm quite happy to believe it's safer than other modes of transport, but I wouldn't be too quick to overstate it. Also, if anyone can explain what "Tubes located on pylons would limit access to the criti…

I'm really impressed to see the entire thing out in the public. They showed the designs, proposed routes, stress analysis, cost analysis... It's quire clear that this isn't just some "Hey I thought of an idea", they really put a lot of work into this.

I was worried this was going to be some pie-in-the-sky idea that was nebulous on a lot of basic details with quite a bit of "we can figure that out later".

Re: Hyperloop

#270

Post by goodcanadian »

cma wrote: post #238
goodcanadian wrote: post #188

I am intrigued, but not overwhelmed. Many of his reasons why his hyperloop is superior to high speed rail are not specific to the hyperloop. For example, you can put railway tracks up on pylons, too, with very little impact on the ground. It is common to do this in urban areas, but it is rarely done in rural areas because it is flat out cheaper to put it on the ground. I don't believe that an experimental tube is goi…

Can you elevate rail as easily? We're talking a lot more weight being carried by the pillars in that case. Plus you don't get the same natural banking off the walls he talks about, which is relevant at these speeds. While rail could bank, you better be going at the right speed when doing so, too slow and you just fall laterally off the tracks.

Can you elevate rail as easily?

The short answer is, "yes." I've ridden on it. The slightly longer answer (as another commenter has pointed out) is that it depends on the weight of the train versus the weight of the hyperloop. I see no fundamental reason to assume that the hyperloop is lighter than the train. It could be so, but then, we could make smaller and lighter trains, too (light rail).

Plus you don't get the same natural banking off the walls he talks about, which is relevant at these speeds. While rail could bank, you better be going at the right speed when doing so, too slow and you just fall laterally off the tracks.

This is a problem even when you are at grade. The solution is known: tilt-trains. The track is banked such that the train will not fall over if it has to stop on the curve. The passenger cabin then tilts with respect to the wheels so that it always feels like the floor is "down" regardless of the speed that the train goes around the curve. The radius of curve sets the maximum speed the train can travel around it.

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