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Comment Re:Maintenance? (Score 1) 115

You cannot have people inside the tube at the same time as vehicles are in the tube regardless, so there's no point to conducting maintenance in a vacuum; you would simply repressurize it (aka, open valves at the pumping stations, or the emergency exits). But there's also no point to ever having people inside. There's nothing except for an accident to damage the inside of the tube; the vehicles do not touch the walls, and it's a very rarified atmosphere, so it's not going to rust from the inside. If there's any need from maintenance, it'd be a need from the outside.

There is one thing that I fault the initial design for, which is the proposal of a two-tube system. This means that if one tube has to go down for maintenance, you have to alternate the other tube between directions, and each time you switch it, wait for it to clear. This would be a big throughput loss. With a three-tube system, you can have the third tube follow whichever direction has the highest demand at whatever point in time, and when one tube goes out you can still keep bidirectional traffic going. Maybe have the third tube be a "stop halfway then continue" design so it can offer service to the valley, at lower speeds.

The other thing I fault the initial design for was for setting it up as a competitor to HSR, which was obviously going to invite a lot of anger against them, and while most of it is just by idiots who never bothered to read the design document, some is legitimate - in particular, that Hyperloop doesn't serve as many cities, or city centers (which they really should have done), like HSR does. I feel that they should have proposed LA to Vegas as the initial leg, so as not to stand in competition to HSR, and so there would be few cities in-between. It's also raise the concept of Vegas magnates funding it; the ability of LA residents to hop to Vegas in half an hour for cheap would be hugely beneficial to them.

As for going into cities: I know they wanted to give a very impressive price figure, and going into cities would have raised that, but as it stands, their price figure was so low that a lot of people refused to believe it (without ever looking at why it was low). A higher price figure because of going into cities would have both made people more credulous, as well as being a more useful, likely-to-be-funded system.

Comment Re:Designed initially by Elon Musk. Really? (Score 1) 115

... which did not involve anything remotely similar to Hyperloop.

Please learn how Hyperloop actually works before insisting that something else is the same. (hint: google "Hyperloop Alpha" and read the design document; it won't take all day). Hyperloop Alpha is neither maglev nor a vactrain; it's basically an extreme version of a ground-effect aircraft flying through a rarified atmosphere, using a compressor to prevent the buildup of a column of air ahead of it by shunting it to the air bearings and behind it - thus allowing it to operate at far-easier-to-maintain pressures and with much easier construction / lighter vehicle mass than maglev.

Comment Re:Hornby set? Maglev is "new"? (Score 1) 115

This is the standard way people complain about Hyperloop.

Step 1) Don't ever bother actually reading the design document, despite the fact that it's not that long and addressess the vast majority of arguments

Step 2) Compare Hyperloop to something not even remotely comparable to it, like the costs of building viaducts for an order of magnitude higher peak loadings, building tunnels with an order of magnitude or more greater cross section, acquiring orders of magnitude more private land, and comparing costs for building through cities with the costs of building through the countryside.

I'd have a lot more respect for its opponents if they'd actually read the design document and actually make comparisons to remotely comparable things. As it stands these threads usually just make me want to hit my head on the wall. At least you recognized the absurdity of the comparison being made.

Train tunnels have to be big. Not only because trains are big to begin with, but because the tunnel walls can't be anywhere the train, or the train will push a big column of air ahead of it, eating energy and slowing it down. Hyperloop tunnels are like aquaduct tunnels - no larger than that of the pipe. Which is sized for capsules, in the non-vehicle version, of two people side by side in First Class-style, semireclined seats.

Comment Re:Distances (Score 1) 115

Peak loadings from the tube are significantly lower than from the cars (I've done the math, feel free to double check for yourself). And a Hyperloop car weighs about an order of magnitude less than a train. The peak loadings are vastly lower.

The amount of track steel per unit length isn't that great; if you were just buying raw steel the cost would be something like a fifth of what's being budgeted for buying the pipe segments for the tube. Rail isn't expensive because steel is expensive; it's way, way down on the list of costs.

Maglev cannot be faster, as it has to plow large amounts of air out of the way (particularly problematic in tunnels - which means that they have to significantly increase tunnel diameters, which significantly increases tunnel costs). The only limitation to Hyperloop speed is the speed of sound in the tube - which can be increased if needed, as discussed elsewhere in this comments section. The amount of vacuum needed is many orders of magnitude less stringent than what you'd normally consider a "vacuum"; it's about a thousandth of atmospheric pressure, versus the millionths or billionths of atmospheric pressure in hard vacuum systems - and thus thousands to millions of times easier to maintain.

Hyperloop is relying on being able to exceed the normal speed of sound without a sonic boom due to the lower air pressure,

The speed of sound does not work that way.

Comment Re:Distances (Score 1) 115

It's not "picking numbers". For god's sake, why does everyone see fit to argue about a system without having read the design document for said system? All of the cost breakdowns are there. It's not that long of a read. It's fine to disagree with something when you know what it actually is you're disagreeing with, but it's ridiculous to assert that something is wrong when you don't even know what that thing is.

Comment Re:Distances (Score 1) 115

The length of the tube expands and contracts dumbass.

Why are you writing that, "dumbass", as if I didn't write precisely that, and explain precisely how it's accounted for as per the document?

The tube expands and contracts. This is accounted for by changing bend radii and changes in length of the tube as a whole at the endpoints.

Also, why are you of the impression that inserting words like "dumbass" into your posts makes you sound more intelligent?

Comment Re:While I'm not exactly one of his biggest fans.. (Score 1) 40

I'd argue that while there's not compelling arguments for "because we can" programmes, there's a very compelling argument for having lofty goals in mind and properly funding those goals. And if those goals include a long-term presence offworld, then that funding means both a robust robotic exploration program, a large systems engineering programme, and most importantly a very sizeable launch cost reductions programme, both the conventional, short term (getting rocket costs down) and unconventional, long-term (exotic forms of launch).

0,5% of the US federal budget plus pittiances from the rest of the world, combined with ever-shifting congressional make-work mandates, does not cut it. 1% plus plan buy-in from congress (particularly those on important committee seats and those in stable seats that are likely to be around for the next 10-20 years), would probably do it. And the rest of the world needs to get off its arse on the space front. Roscosmos's budgets are a shadow of what they used to be. China's space industry is booming, but still relatively small. JAXA's could use to be better. ESA's is tiny compared to the size of the EU economy. But I guess people don't see it as a priority - even though the public thinks we're spending vastly more on space than we actually are and are by and large okay with that.

Comment Re:I call BS (Score 2) 138

The referendum was the worst possible way to settle this issue.

- The question was too vague. Remain in or leave the EU, but what about the single market? Freedom of movement? What kind of deal should we try to get? Norway model, fall back to WTO rules?

- The "debates" in the run up were awful, a complete shambles.

- The whole thing went post-truth almost immediately.

- Most voters were extremely ill informed, by design. They wanted to know things like what the economic consequences would be, what sort of deal we would try to get, and the leave campaign was careful to avoid offering a plan that could then provide answers to those questions.

- The while EU issue was conflated with immigration, which we could control today without leaving if we wanted to.

Comment Re:Distances (Score 1) 115

It seems extremely unlikely that maglev would cost more than a hyperloop tube. The tube still needs the same support under it, maybe a little less due to smaller cars but a little more due to the mass of the "track" being higher. It's more material to fully enclose the area, and would need air pumps all along it to create the partial vacuum.

Maglev may ultimately be faster too. The problem with hyperloop is that you have to balance the need to fly on air bearings and the need to shift air out of your way in an enclosed space. When you get up to higher speeds you need to pump the excess air from the front to the back. They are hoping they can keep improving the vacuum but then you waste more and more energy maintaining it and a failure becomes more and more catastrophic.

Maglev can push the air aside with a long nose cone because even tunnels are not nearly as confined as the hyperloop tubes.

Hyperloop is relying on being able to exceed the normal speed of sound without a sonic boom due to the lower air pressure, but it looks theoretically possible to design a maglev that could cross that threshold without the boom disturbing people. It's something JAXA is working on for aircraft and which JR has put a lot of effort into for current trains which would run faster if not for the noise.

Comment Re: I call BS (Score 1) 138

In that case, why not argue the opposite? Extend the vote to the entire EU. If other EU country's citizens don't bother to vote, that's their problem, but the result is democratic and binding on all of them.

In any case, there was no question about hard or soft Brexit, staying in or leaving the single market.

Comment Re:I call BS (Score 3, Informative) 138

Was there anything in that Brexit referendum that drew such a nuanced line b/w a 'hard' Brexit vs a 'soft' Brexit?

Yes. Depending on which Leave campaigner you asked (there was an official campaign, an unofficial campaign, a lots of random people weighing in) they were either demanding an extremely hard Brexit or trying to reassure people that it would be a soft Brexit and little would really change.

There is no mandate for a hard Brexit. The Leave side only won by 52% to 48%, and it's doubtful that everyone who voted to leave also wanted a hard Brexit. At best, the question wasn't even asked.

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