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Agreed. > She says the pipes could come up on state-owned land beside motorways or (where they exist) railways. No time or planning should go into surface hyp
by breck 6y ago
Agreed.
> She says the pipes could come up on state-owned land beside motorways or (where they exist) railways.
No time or planning should go into surface hyperloops. These things belong underground. 100x better.
- TylerE 6y agoSay what? That’s crazy talk. Underground would be many times more expensive, and has much worse failure modes. What happens if the train loses power?
- alacombe 6y agoDidn't Musk's "Boring Company" solve the problem of underground boring cost ?
- j88439h84 6y agoThey'll be stuck in a tunnel. Is that worse than being stuck in the desert?
- TylerE 6y agoYes, if you have no ventilation. If you're above ground you'd just pop an emergency hatch in the tube. You can't do that underground. I'd also point out that a hyperloop tunnel is a much worse place to be stuck in than a normal tunnel. In a normal tunnel there is room to walk alongside the tracks. In a hyperloop tunnel there is virtually no room between the car and tunnel - maybe an inch or two, tops.
- jengleton 6y agoYou might not want to pop the emergency hatch when you're surrounded by vacuum.
- TylerE 6y agoHatch in the tube, not the car.
- liability 6y agoHeh, look up "vacuum cannon" on youtube. The tunnel would need to be slowly depressurized, otherwise anything in it would turn into a bullet when the atmosphere rushes in. This also applies to any sort of failure that compromises the vacuum. A dipshit with a rifle could kill anybody in the system in a fraction of a second. Burying the tubes is probably the only way to avoid this, but thankfully the whole thing is vaporware anyway.
- aeternum 6y agoYou don't need a full vaccum. Even half an atmosphere would greatly reduce air resistance and allow for 4x the velocity in 1 atm. Humans can survive (uncomfortably) at .5 atm and you eliminate the vacuum cannon problem simply by putting pressurization valves periodically throughout the tube.
- godtoldmetodoit 6y agoThe tube is vacuum, you'd need an airlock not just a simple hatch, no? How do passengers get from car to airlock without a suit?
- TylerE 6y agoDepressurize the tube first.
- deleted 6y ago
- chrisco255 6y agoIt's not crazy talk. The truth is they likely belong both above ground and below ground, depending on urban density or geography. And tunnels tend to have escape ladders every so many feet.
- thephyber 6y agoElevated train platforms may have escape ladders, but I thought the Hyperloop tube was depressurized and the car within it needs to be pressurized. This poses a problem for the escaping passengers before they reach the ladder.
- chrisco255 6y agoIt's only a partial vacuum from what I understand. I'm not sure what kind of difference that makes but presumably it would be easier to depressurize in an emergency.
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- erikerikson 6y agoAren't all real world "vacuums" really only partial vacuums?
- breck 6y agoYou're wise to point out historically tunnels were more expensive. And I shouldn't be making claims without a bigger dataset in front of me. I'm just extrapolating from trends and some cherrypicking. The ongoing elevated rail project in Hawai'i is now running at $500M per mile. Boring Company projects they can get cost of tunneling down to $10M per mile. What I forecast (without much data, so please correct me if I'm wrong) is that with more money going to tunnels, we will see the costs continue to drop. You don't have the quasi-extortion that goes on now over land rights above ground. Tunnels also scale better long term—you can just keep adding tunnels. But beyond cost and scale tunnels are just so much nicer. You can replace ugly, polluting above ground infra with parks and greenery. Even though the Big Dig in Boston took forever and went way over costs, the city is so much nicer now without the Central Artery.
- jcranmer 6y ago> I'm just extrapolating from trends and some cherrypicking. The ongoing elevated rail project in Hawai'i is now running at $500M per mile. Boring Company projects they can get cost of tunneling down to $10M per mile. Note that you're (or, rather, Elon Musk is) comparing apples and oranges. Tunnels are actually cheap, about $80m / mile. The expensive parts of metro systems is not the tunnels, but the things that go inside them and stations. This is doubly so for the inexcusably high costs of US transport construction. When people talk about the cost of metro systems, the divide the total cost of the expansion (or entire system if it's a new one) by the length of the system, so they include the amortized costs of new vehicles, infrastructure inside the tunnels, and stations (which often cost more than the tunnel to get to them! Station excavation isn't cheap).