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Hyperloop

spacex.com

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Re: Hyperloop

#961

Post by stcredzero »

jellicle wrote: post #544
gojomo wrote: post #493

Earlier quoted context omitted.

Density is destiny. Population densities: 407/km² England 256/km² UK 93/km² California 32/km² USA

But this comparison is wrong and meaningless. Certainly no one would build a high-speed, dense train network across, say, Nevada. But building one across the coastal part of California? Or across the NE United States? Why yes, that does make sense, and why yes, it is warranted by the densities in those areas. The fact that the U.S. also owns Alaska doesn't really matter. No one is arguing Alaska needs a high-speed ra…

> Certainly no one would build a high-speed, dense train network across, say, Nevada.

I wonder. It's easier to find low cost airfares to Las Vegas than other cities. A conduit to Las Vegas from the populated west coast might be interesting to some.

Re: Hyperloop

#962

Post by DannyBee »

benjamincburns wrote: post #866
DannyBee wrote: post #329

Earlier quoted context omitted.

Railway track built above ground has to support weight of the cars, which seems significantly higher ....

Unless Musk has found a way to make the cars weightless, the tube must support the weight of the cars. Further, the pylons must support the weight of the tube and the cars, over a smaller footprint.

Railway cars weigh approximate 30 tons (unloaded) to 140 tons (loaded).

Even a Ford F150 truck only weighs 2 tons.

Re: Hyperloop

#963

Post by dojomouse »

kamjam wrote: post #583
Maxious wrote: post #570

Earlier quoted context omitted.

Too late: http://www.seattlepi.com/technology/businessinsider/article/... > If you don't want to be searched at the train station, you have the freedom to not ride the train.

I wonder what the security checkpoints would be like on the HyperLoop if it ever got built? They are saying capsules could depart 30 seconds apart. Imagine is there was an attack in on of them, with several others travelling at high speed just behind. http://www.bbc.co.uk/news/world-us-canada-23677205 I'm sure there some contingency has been thought of, unfortunately it's just the world we live in these days :(

The Shanghai maglev has no security at all... or at least not last time I went on it. Neither do any of the European HSR systems I've been on.

Remember a big part of TSA isn't to protect the people on the planes, but to protect other people from the planes themselves. It's pretty hard to weaponize a vehicle that's stuck inside a tube or on rails.

Re: Hyperloop

#964

Post by dojomouse »

tinco wrote: post #438
ibudiallo wrote: post #412

Earlier quoted context omitted.

Bill gates can reach for his wallet and fund this. He won't even notice it. Someone get me his phone number right this moment.

Bill Gates has more important things to spend his money on than moving rich americans from somewhere in America to somewhere else in America.

Actually Bill Gates is on record saying that if he had 'one wish' it would be for an awesome low emissions energy source.

When you consider the growth in air travel, and the fuel options for air travel, the Hyperloop IS effectively a low emission energy source. I suspect he's more than interested.

Re: Hyperloop

#965

Post by dojomouse »

enraged_camel wrote: post #608
anko wrote: post #577

Earlier quoted context omitted.

I think tesla motors releasing an affordable car would benefit the world a lot more than the hyperloop. But it's nice that he is presenting the idea so the world can do their own analysis and even implement it before he has the chance.

>>I think tesla motors releasing an affordable car would benefit the world a lot more than the hyperloop. Specifically, an affordable Tesla car could benefit the entire world, whereas the Hyperloop would (at least initially) only benefit people living in LA and SF.

Really specifically, an affordable Tesla would (at least initially) benefit only those who were able to buy an affordable Tesla given the still significant cost and Tesla production constraints.

They both have the potential to be hugely beneficial to the entire world. Although in Tesla's case it's more of a certainty... fortunately we can have both :-)

Re: Hyperloop

#966

Post by dojomouse »

jessriedel wrote: post #281
jeffasinger wrote: post #229

Earlier quoted context omitted.

The tube is not nearly as wide or heavy as a traditional train, so I don't know that it's fair to say that you can just as easily put a train up on pylons as you could this tube. It's interesting to think about, but also there are probably much higher costs associated with a completely untested system like this than estimated. I wouldn't be surprised if this system, if it actually worked at all, ended up being more e…

But why make it a traditional train? Just build a lightweight train if it gets you all of the hyperloop's cost advantages without the additional costs and complexity of a tube?

Above a certain speed wheels present huge issues, which means you need to change your drive mechanism and suspension mechanism.

Also, drag is a huge killer of efficiency and hence overall economics. Even at 500kph the drag on a train at sea level is enormous. At 1000kph it's 4 times bigger again, and you've got the sound barrier to worry about. Trying to do the same with multiple small capacity trains is astronomically worse. So, better to have reduced drag... and by now you've basically got the hyperloop.

Re: Hyperloop

#967

Post by dojomouse »

omegant wrote: post #393
julian37 wrote: post #287

Earlier quoted context omitted.

Isn't that the case with planes also? As far as I know, at 35,000 feet altitude you'd die, too, if cabin pressure drops and the plane's life support system fails. And I don't recall ever hearing of an air plane accident that involved suffocation.

Look at the Armstrong limit (at 62,000´), a mayor problem to overcome if the tube is going to be at the equivalent pressure of 150,000´ http://en.wikipedia.org/wiki/Armstrong_Limit http://en.wikipedia.org/wiki/Time_of_useful_consciousness Also look at the TUC (time of useful consciousness) that it´s below 5 secs when flying that high. That means that you have less than 5 secs to put your oxigen mask on before you los…

The great thing about the hyperloop, and other vactrain systems, is that you're at sea level... you're just not in atmosphere. The atmosphere can be restored in seconds. Sure, it'll stop the entire system and be a TOTAL pain in the arse because you'll have to restore the vacuum, but that's acceptable as long as it doesn't happen often.

Re: Hyperloop

#968

Post by mgaphysics »

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…

This may very well be at the heart of his submission, especially since he is the first to point out that most of the real kinks have not been worked out.

What do most of us in the general public really know about how projects like the high speed rail get on the ballot. A lot of people have their suspicions, but we have to ask ourselves if there was a competitive bid process to determine the best solution.

I, for one, would have voted to throw money into future technologies over current rail solutions. Mostly because I shudder to think how much current tech will be old news in ten years when the high speed rail is completed (if at all).

If we pursue the hyperloop or similar tech, and whether it can be completed or not, at least it would be a first of it's kind and on the cutting edge.

Re: Hyperloop

#969

Post by dojomouse »

dkrich wrote: post #231

The main reason why air travel continues to be the most practical, cost-effective means of high-speed transport is that the politics involved in connecting two points with a transit system are enough to make you lose faith in humanity. Take for instance, the DC metro system. There is an expansion underway to extend the system west to Dulles Airport, about 30 miles or so from downtown DC. A huge project, no doubt, but…

It depends on where you are. China is expanding their high speed rail network like crazy. 10,000km of line between 2007 (when it was created) and end of 2012.

So the question is not whether projects like this can happen, but rather whether politicians in the USA can be beaten into allowing them to happen there.

Re: Hyperloop

#970

Post by dojomouse »

jacquesm wrote: post #258

I'll just leave this here: http://jacquesmattheij.com/elon-musk-and-the-hyperloop Looks like I nailed most of it. So, who is going to build a proof-of-concept scale model of this thing a few kilometers long?

Really? I guess you got the tube part right.
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