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Comment Re:Terrorist target? (Score 1) 55

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) 55

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.

Comment Re:Think of why maglev is expensive... (Score 1) 55

Why are you under the impression that putting it in a tube makes handling turbing forces, stopping forces and control more difficult? Inside a tube, all motion is perfectly constrained, and you have a tremendous amount of surface area to magnetic brake against.

The turning radii issues are of course real, and are highly addressed in the Hyperloop Alpha document. Likewise for dimensional precision. For smoothness, their solution is a radial polisher which drives down the tube behind the pipelaying crew and smoothing out each orbital weld (and the pipe itself). For straightness, alignment is maintained by the same suspension/alignment system they use to deal with earthquakes.

As for why maglev trains are expensive - trains are expensive for a wide variety of reasons. Land acquisition and permitting is often the most expensive. Tunnels and viaducts are often a very large component as well. Maglev technology itself often tends to have high bills.

Hyperloop (as per Hyperloop Alpha, not the student competition) isn't maglev, it's an air bearing system. Skis, basically. The pipe is built the same as oil pipeline, and the budget is similar to that of oil pipeline budgeting per unit area per unit distance (oil pipelines have harder environmental issues to overcome and much higher loadings, more significant temperature management issues, etc, but lower precision / straightness requirements, so it's probably a wash). Tunnel cost is minimized by minimizing tube size (the budgeted tunnels are standard rates for tunneled pipe in non-urban areas). Viaduct costs are minimized by a key design feature of Hyperloop - minimizing peak loadings by having frequent, small vehicle launches rather than infrequent, large vehicle launches. Viaduct costs tend to track their peak loading.

As for land acquisition, the costs in Hyperloop Alpha are kept down by a combination of design and cheating. As per design, it's designed to be small enough to fit elevated into highway medians, with the low peak loadings, making overhead suspension an affordable option. Such places are state land, and already permitted for far more environmentally harmful activity (road traffic). This of course requires state buy-in to the concept, but states often specifically pursue high speed transport options. Private land acquisition is limited to places needed to maximize turning radii, and in-city for stations. The latter is the other place that they cheat - Hyperloop Alpha avoids cities. LA and San Francisco are served by it, according to the design, like airports on the outskirts of town; people have to get connecting legs into town. But that would be an unpopular decision, and you would expect the state to insist on greater accessibility (airports are only out of town because they have to be, not because that's a desirable location). Likewise it bypasses cities en route, unlike HSR. Basically, it's designed as something halfway in-between HSR and air travel (both in terms of service and throughput), but targeting much lower prices, higher speeds, and a lower energy footprint.

In short, it's budget savings vs. HSR are somewhat of a combination of cheating (cutting out a lot of what HSR does) and design (keeping track loadings down, profile small, build in the same manner as an established industry (pipeline), and moving your hardware (capital expense) through the system as quickly as you can.

Comment Re:Distances (Score 1) 55


Part of the whole point of Hyperloop is that the low pressures aren't extreme (it's not a hard vacuum), and are thus easier to maintain with a regular series of vacuum pumps. And it has no "joints" (the only interruptions being periodic emergency exits, and the pumps themselves). All of the pipe segments are orbital welded and then polished smooth.

Comment Re:Use that low pressure air (Score 1) 55

Wheels at low speed, not maglev.

Of course, the "Hyperloop competition" blurred the line as to what counts as "hyperloop" anymore, because it was based around a bunch of purely maglev options that were radically different from the Hyperloop Alpha design (in many ways beyond just the levitation means).

Comment Re:"They" don't have to understand anything (Score 1) 585

Don't forget that Socialism has no monopoly on force. Our current capitalism is full of forced situations, some by government and some by businesses. I am forced to pay a doctor if I need a prescription, even if I know what I need. I can't get an x-ray without the radiology consult. I am not permitted to convert my front yard to food crops, so I must pay the grocery store. I'm not supposed to do my own electrical work even if I exceed code. Many restaurants have a problem if they want to offer Coke and Pepsi products at the same time. Sometimes you can't buy parts for appliances and home electronics unless you've also paid a few thousand to be a "certified" technician (basically, certified that you've paid them a few thousand, that is). Same crappy deal for modern automotive diagnostics.

The lack of a basic income also creates a force situation for many. Work when we say and as much as we say and you'll take what we're willing to pay. Be sure to kiss the manager's ass or you'll be even worse off.

Some of that force comes from government, some from businesses.

Comment Re:I don't buy it. (Score 1) 28

We already know that the US intel community released a report where they lied about Russian hacking of the US elections.

So, why should I believe, again without proof, that the attack was from the Russian state?

For someone demanding, proof, you're quick to throw the "lied" word around without providing any.

There was a publicly released report, and "without proof" != "included proof that I disagree with."

Dasvidaniya, boyevik.

Comment I tried to warn a friend (Score 3, Interesting) 585

A few years ago, a friend of mine who had been working in a full-time job in the hospitality industry, had signed up to be an Uber driver during his spare time. He claimed to be making an extra thousand dollars a month or so, which he used to finance a used vehicle.

I probed for more details. "What about insurance," I asked. "Have you accounted for wear and tear on the vehicle due to increased mileage? Is this a sustainable income model? What if the pool of drivers increases and you face increased competition for fares?" He was completely nonchalant: at the time, Uber was still growing, there weren't as many drivers as there are now, and since he was still receiving a salary, he had no concerns for wage instability.

Months later, he mentioned that he quit his full time job because he could make more money driving for Uber, and it was lower stress. He seemed happy. Well, we know how that turned out. He ended up essentially destitute, unable to afford food and rent; unable to fix his car when the inevitable breakdown occurred and would cost thousands to repair; and still had payments to make on the loan.

I'm not saying that these kinds of jobs cannot be sustainable as full-time employment, but it is a great deal more difficult to make it viable than the vast, vast majority of people enticed into the idea are led to believe. The fact that these companies make it sound like it's easy (for obvious reasons) is the modern-day equivalent of selling Amway.

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