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Comment Re:That's great.. (Score 1) 78

I'm thinking that because of a lack of water in a particular part of the planet is the issue being brought up. Given water evaporation in pumping then isn't it being lost in the right area that is perceived to be needing it? Looks like the Chinese government has to choose between gambling on a cloud being able to rain, or calculating for evaporation on a sure thing. I guess that's why they make the big bucks?

Comment Re: Nefarious uses? (Score 1) 78

That would explain a lot. It also answers a lot of questions that the pundits have asked. It would also play into the myopia of the Clinton CHQ, and the DNC. This would also make a great game and movie title. There is one question I don't have an answer to, "did the DHLS enjoy the Lard Ass and Chief's pep talk?" I guess we'll see. LOL

Comment When The Lights Go Out In Your City (Score 1) 284

There currently exists two sources of energy access that do not require the electric company; Solar, and Wind. One the easiest ways to handle a corporate greed brown out is to simulate one. Then go about constructively solving this future PITA problem. It will take some time before there's a dump tower electric company near you, but you can bet your inner breed meth addicted trailer park rent on it; it is coming, for you.

Comment Re:Distances (Score 1) 108

Technically you can scale Hyperloop to several times higher speeds, if you can build sufficiently straight segments (e.g. Great Plains). It does however require one alteration of note: you have to increase your leak compensation pumping capacity severalfold (it's an unknown at this point how bad leaks will be, though they tried to be pessimistic in their assumptions), while injecting hydrogen or helium to maintain the same pressure. Ideally hydrogen (it's not explosive nor embrittling at such tiny pressures, although its behavior when compressed would need to be studied). You need light gases to raise the speed of sound inside the tube (also reduces air resistance / compressor mass throughput requirements). Water would work also instead of hydrogen or helium (it's a gas at those pressures), although not as well (but better than air).

At least, pessimistically it's required. I don't think they've done anything to simulate what sort of temperature the rarified gas inside the tube would maintain under full load (the effect of passing vehicles on the tube itself is trivial - the gas is a terrible conductor of heat, and the tube has a huge convecting surface area). If the rarified gas was left significantly hotter than the tube (due to its poor conduction of heat), that too would raise its speed of sound.

Comment Re: Distances (Score 1) 108

Same solution Japan uses for high speed rail. You're in a tunnel. Now you're out and instantly on a bridge! Now you're off and instantly in a tunnel! Now a bridge! Tunnel! Bridge! Tunnel! Bridge! (repeat until you arrive at your destination)

That said, tunnel costs are proportional to diameter and bridge costs proportional to peak loading, so a Hyperloop-style system wouldn't be such a bad idea in such an environment.

Comment Re:Distances (Score 1) 108

A more detailed breakdown of the differences versus high speed rail in general is in this post.

As for versus maglev: maglev is even more expensive to construct than conventional high speed rail, and suffers from the same design challenges that Hyperloop is designed to eliminate. Beyond that, Hyperloop is entirely self-powering - it uses so little power (coasting the vast majority of the time) that it's easy to have enough solar panels atop the tube to provide for its energy needs. Anything not in a rarified atmosphere moving at those sorts of speeds is plowing against a large amount of air resistance.

The small size of Hyperloop cars is a feature, not a bug; it's not just the cross section that's kept down, but the length as well. By keeping cars small (but frequently launched for equivalent throughput), they minimize peak loadings. Viaduct costs are roughly proportional to peak loadings. Elevation allows them to reduce a huge amount of overhead costs (the majority of the costs of a typical rail project) and eliminates a lot of the technical challenges with HSR involving ground shifting and earthquakes, transferring all of your support to readily adjustable fixed points.

As for passenger comfort, the interior looks more comfortable than any train I've ever been on. Of course, you can't get up and walk around, but then again, trips are so short there's not really any need to. I would say that the excellent leg room would be great for stretching out for napping, but that would be a very short nap ;)

As for loading, multiple capsules are loaded up at once. It's not a one-at-a-time thing.

Comment Re:Distances (Score 2) 108

What is so difficult for you about reading the design document, "dumbass"? Did you really think that that isn't covered? Section "Earthquakes and Expansion Joints". The tube is not firmly affixed to each pylon; it's mounted on a multiaxis damper. Its positioning is automatically controlled relative to independent factors, including earthquakes, ground shifting over time, and daily thermal expansion (which results in planned for anticipated changes in bend radii as well as a net overall expansion or contraction at the endpoints)

What it is about some topics that convince people to go online and write rants without having read the design document? It's not that long, for crying out loud. It's one thing to disagree with a particular engineering decision. It's an entirely different thing to have no clue what the engineering decisions are but still rant anyway.

Comment Re:Use that low pressure air (Score 1) 108

Inductrac is less efficient than air bearings and the track is more complicated to build than straight pipe. That said, if the air bearing concept proved unworkable, I'd think it a fine fallback alternative.

The costs of the turbomachinery on the current design is factored into the budgeting. And you need it either way unless you're planning to run a hard vacuum, since otherwise the vehicle will compress the column of air ahead of it. Industrial air compressors aren't exactly new technology, although the operating environment is admittedly a bit unusual ;) But I do have to agree with their choice of focusing on air bearings. They're simple, light, equal or greater efficiency in comparison to magnetic, and most importantly they keep the "track" simple. The main downside is that they require a fairly high wall smoothness (hence Hyperloop Alpha's need for a rotary tube polisher).

Comment Re:Terrorist target? (Score 1) 108

If you're going to detonate bombs large enough to take out a concrete column for a big steel pipe, why wouldn't you do it where you'd kill a lot more people rather than "hopefully lucking into causing enough deflection (by increasing the span) right before the next capsule arrives that it can't decelerate sufficiently in time to handle said deflection, and possibly killing or injuring one capsule's worth of people"?

Airplane attacks were popular because of the ability to kill hundreds of people at once, or to hijack planes and use them as weapons. Not exactly applicable to Hyperloop. And even airplane attacks seem to be falling out of popularity, in favour of coordinated shootings and plowing through crowds.

Comment Re:Hornby set? Maglev is "new"? (Score 1) 108

If you think the pressure maintenance figures in the Hyperloop Alpha document are unreasonable, cite the actual numbers you disagree with and explain why.

The main advantages over air travel are that the pressure is much lower, frontal area much lower, allowable spacings far closer (no "air traffic"), no noise pollution, no air pollution, and efficient, direct acceleration of the vehicles, with the tube itself serving as a mounting point for the solar panels that power it.

You clearly have never read the Hyperloop Alpha design document. It does include diversion options. There are regularly spaced emergency exits across the track. Vehicles brake to a stop then roll on wheels to the nearest emergency exit.

As for security: the cars are about the size of monorail cars. So if you're going to assert random things about what security will be like, why not assert it'll be like monorail security?

Yes, the design fundamentally does not work if it's not driverless (you really should read the design document before discussing it).

The costs of tunneling are included in the budgeting in the design document (again, you really should read it). There is no "50km long 7,6m diameter undersea tunnel" leg to it.

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