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Hyperloop

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331–340 of 983 posts

Re: Hyperloop

#331

Thought this was amazing: $20 for a one-way, 35 minute trip from SF to LA.

$20 plus operating costs. That is, the $20 is just the additional cost to pay off the capital cost over $20 years, and doesn't include any of the amount necessary to pay the operating costs.

Airline tickets would be pretty cheap if all they were paying was the 20-year amortized capital cost of the airplanes + airports, too.

Re: Hyperloop

#332
post #251

Earlier quoted context omitted.

This is genius.

This is also disgusting. Can you imagine a Greyhound where every seat was also a toilet? I would definitely think long and hard before riding it.

I was being facetious.

Re: Hyperloop

#333
In Brazil the building of a new high speed train between São Paulo and Rio was just delayed for the third for for lack of interested companies to build the system. The estimated cost is at US$ 17B.

There are not earthquakes in Brazil and the length should be around 500km. It seems like a better candidate than SF-LA.

just saying,

Re: Hyperloop

#334
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…

I like to think (hope?) that when a world changing idea comes along (and if this does work as described, it definitely is world changing), everyone can work together and implement it in a reasonable time frame. I think one of the reasons many projects take so long to complete, like the California HSR, is because the cost to benefit isn't all that great. It has no advantage over flying and little to no advantage over driving.

Re: Hyperloop

#335

Earlier quoted context omitted.

Same thing that happens if you develop unexpected gastric issues during a 30 minute plane flight, I'd imagine, since you'd spend the whole time strapped in for take-off and then landing.

I'm pretty sure in this case they would let you go to the bathroom.

I've been rudely informed to go back to my seat when I tried.

Re: Hyperloop

#336
The pressure difference is higher than in a passenger jet. The pressure vessel must be a tubular structure with small well sealed doors. None of this prism with whole fuselage gull wing door stuff.

Re: Hyperloop

#337

Earlier quoted context omitted.

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.

The output of the compressor is at 1000 deg. F and 300 psi. That is pretty scary.

The combustion temperature of JP-4 is 3,688 °C.

Re: Hyperloop

#338

That capsule ( http://images.bwbx.io/cms/2013-08-12/0812_Hyperloop_605.jpg ) looks like a claustrophobic's nightmare. Otherwise very, very cool.

I get the feeling the space in the passenger car (which is limited) was designed by people who build space capsules.

Have you ever been in submarine?

Re: Hyperloop

#339

Earlier quoted context omitted.

> When a train exceeds the shear wave speed, ground-borne vibration waves "build up" in a manner similar to the shock wave created in air when a plane exceeds the speed of sound... Putting the railway or tubes on pylons would give you an opportunity to dampen or otherwise transform those vibrations wouldn't they?

Putting the railway or tubes on pylons would give you an opportunity to dampen or otherwise transform those vibrations wouldn't they? Maybe, maybe not. Guideway supports (pylons) are typically founded into the bedrock which does reduce vibration somewhat, but the vertical motion of the pylon moving against the soil will still generate shear waves. This is why a demonstration project would be useful.

I recall reading that the pylons had vertical and horizontal dampers to protect against earthquakes (among other minor natural changes), so wouldn't those dampers be able to cancel out the shear waves?

Re: Hyperloop

#340

Earlier quoted context omitted.

It was approved by a ballot measure, so in this case it may be the "idiocy" (or will) of the voter. http://ballotpedia.org/wiki/index.php/California_Proposition...

I'm not from the area, so I don't know how such a ballot works but for voters who didn't have Musk-level engineering knowledge, was the choice the status quo of not fast trains and spending on fast trains?

The choice was fast trains or no trains.
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