It’s time to be honest about Musk’s vacuum tube to nowhere

  • ExLisper@linux.community
    link
    fedilink
    English
    arrow-up
    13
    arrow-down
    30
    ·
    10 months ago

    it’s impossible to be build from the technical point of view. even if you do manage to miraculously built it it won’t be economically feasible.

    I don’t think you can say any of this until you actually put some money into it and check. Technology improves all the time and with it economics of such project. They didn’t really try to build any actual routes. They just tried to do some prototypes and check current feasibility. I don’t see this as a scam or a bad thing at all. No public money went into this.

    • nova_ad_vitum@lemmy.ca
      link
      fedilink
      English
      arrow-up
      24
      arrow-down
      3
      ·
      10 months ago

      A very long evacuated tube hundreds or thousands of miles long - too long to ever be actively defended - is itself fundamentally untenable. There are US states where every “welcome to ___” sign is shot up with holes. You don’t think people will take potshots at this thing?

      Even if you somehow made it armoured and immune to small arms (this would be the largest armoured thing ever constructed), it would never make any sense over cutting edge high speed rail that doesn’t require an evacuated tube.

      This all comes straight from first principles. To change this, any number of fantastical technologies would need to be invented (maybe the tube can be made of vibranium?).

      • Death_Equity@lemmy.world
        link
        fedilink
        English
        arrow-up
        18
        ·
        10 months ago

        What I always thought was the worst part about the idea is pressure equalization in the event of an eventual cabin seal failure.

        • MonkeMischief@lemmy.today
          link
          fedilink
          English
          arrow-up
          5
          ·
          10 months ago

          Yeah I think we’ve learned all we need to know about the mega-rich “MoVe FaSt AnD bReAk ThiNgS” types and their highly pressurized people-carrying cylinders…

      • grue@lemmy.world
        link
        fedilink
        English
        arrow-up
        7
        arrow-down
        3
        ·
        10 months ago

        You don’t think people will take potshots at this thing?

        Given that I always heard it being envisioned that the evacuated tube would be a tunnel, no, I don’t.

        • nova_ad_vitum@lemmy.ca
          link
          fedilink
          English
          arrow-up
          3
          ·
          10 months ago

          Just I’m clear on this the plan is/was to dig a large diameter tunnel underground, between cities?

          • grue@lemmy.world
            link
            fedilink
            English
            arrow-up
            1
            ·
            10 months ago

            As far as I know, yep. That’s how “The Boring Company” fit in to the scheme.

      • ExLisper@linux.community
        link
        fedilink
        English
        arrow-up
        9
        arrow-down
        12
        ·
        edit-2
        10 months ago

        Yeah, that’s why we don’t have any thousands mile long tubes transporting dangerous substances. Oh, wait. We do! What happens when someone shoots a gun at them? They go to jail! (look up Daniel Carson Lewis of Livengood).

        In your theory, why can’t the same laws protect ‘railway tubes’ that protect oil and gas pipelines? Why terrorist don’t shoot guns at pipelines all the time? Why don’t terrorist jump on high speed rail tracks and sabotage them? Where I live there’s 5000 km of high speed tracks that are not “actively defended”. There’s just a fence. Big rock could take out a train. Why do you think no one ever attacked it but everyone would be shooting at hyperloop pipes for fun?

        Oil pipelines are often buried underground, they can have up to 60’’ in diameter. Hyperloop pipe is about 90’’ in diameter. It could be feasible to put it underground. I’m not saying it’s a good idea or bad idea. I’m just saying that some guy commenting on a blog is not a good reason not to try. Get enough of good engineers to work on it for a while and you will know if it’s feasible or not. That’s what they did. I think it was a good thing to try.

        • nova_ad_vitum@lemmy.ca
          link
          fedilink
          English
          arrow-up
          13
          arrow-down
          1
          ·
          10 months ago

          Yeah, that’s why we don’t have any thousands mile long tubes transporting dangerous substances.

          None of those are vacuum tubes. This is nonsense.

          What happens when someone shoots a gun at them?

          They leak. Literally all the time. They keep working. This won’t.

          I think it was a good thing to try.

          Okay well you got there eventually.

        • sir_reginald@lemmy.world
          link
          fedilink
          English
          arrow-up
          8
          arrow-down
          3
          ·
          10 months ago

          I’m just saying that some guy commenting on a blog is not a good reason not to try.

          The good reason not to try is that bullet trains have proved working perfectly in other parts of the world. Sure, they would be slower than an hypothetical hyperloop but they are a working technology that would help alleviate the transportation problem.

          Why invest in a project that might lead nowhere?

          I’m not anti experimentation, by any means. It’s just that as the article says, the hyperloop was proposed when a bullet train was being discussed by local politicians.

          • ExLisper@linux.community
            link
            fedilink
            English
            arrow-up
            4
            ·
            edit-2
            10 months ago

            Test hyperloop track was supposed to be build close to where I live, in Antequera, Andalucia, Spain. There’s a railway test center built specifically for testing new rail technologies. Since it was build decades ago nothing was really tested there because bullet trains already existed and no one had any new designs since then. The trains didn’t really change since 1980s. At the same time bullet trains still lose to planes on longer routes because they are simply too slow. Hyperloop was supposed to change this and offer rail technology that would compete with planes on long routes. It was supposed to be the next step in rail travel that would be able to compete with air travel. Now we know it wasn’t feasible but just because it’s not right for USA it doesn’t mean it’s not worth testing.

    • jonne@infosec.pub
      link
      fedilink
      English
      arrow-up
      15
      arrow-down
      1
      ·
      edit-2
      10 months ago

      I’m assuming it’s probably technically possible, just ridiculously expensive to build and maintain, with way less throughput than a train.

      • ExLisper@linux.community
        link
        fedilink
        English
        arrow-up
        4
        arrow-down
        8
        ·
        10 months ago

        Again, maybe it is but you can’t really be sure until you design it, estimate the cost, try to lower it by modifying the design and if it’s close try building some prototype to test it. People keep talking like you can evaluate design like this on a napkin. That’s just not how engineering works.

    • gens@programming.dev
      link
      fedilink
      English
      arrow-up
      9
      arrow-down
      2
      ·
      edit-2
      10 months ago

      No, it’s just not viable. Just maintaining the vacuum is hard and takes a lot of energy. Keeping it from imploding onto the high speed train is also very hard.

      It does not need experimenting, it is known already.

      It is and always was a scam (or just simple stupidity, or both).

      • ExLisper@linux.community
        link
        fedilink
        English
        arrow-up
        2
        arrow-down
        3
        ·
        edit-2
        10 months ago

        Yeah, I wouldn’t really trust any of that unless it came from interdisciplinary team of engineers that actually looked into it. I know that there’s a lot of bloggers and youtubers that like to shit on every new idea but they are often wrong and are simply trying to create clickbait content.

      • BoscoBear@lemmy.sdf.org
        link
        fedilink
        English
        arrow-up
        2
        arrow-down
        3
        ·
        10 months ago

        Why is a vacuum (holding a tube in compression and 10-14psi ) harder than pressure (holding the tube in tension at 200-1500 psi).

        • naevaTheRat@lemmy.dbzer0.com
          link
          fedilink
          English
          arrow-up
          2
          ·
          10 months ago

          I used to work in a vacuum lab and one thing to consider is pumping efficiency drops as pressure drops. So everything leaks all the time right, and one strategy is to just pump harder.

          However at low pressurers nothing is pushing the air into the pump for extraction, something like a bend can stop gas flowing around it dramatically where in high pressure the gas behind just pushes it through. So it gets more and more energetically demanding to keep pace with leaks.

          Also pressuring a giant tube to multiple atmospheres also sounds like a nightmare. It’s hard enough to keep pool toys inflated :p

            • naevaTheRat@lemmy.dbzer0.com
              link
              fedilink
              English
              arrow-up
              3
              ·
              10 months ago

              Just to talk in international units to include everyone: I was under the impression it was supposed to operate at 1 mbar or 1/1000th of an atmosphere. That’s into the transition between viscious and molecular flow iirc (for air at normal temps anyway). You’re probably still pumping down with something like a scroll pump but it’s not very efficient anymore.

              Thinking about the number of opportunies for leaks. Every joint, every screw, every pump connection. How they all shift against each other as the sun warms and cools them, how you relieve the strain without introducing pourous materials. It’s a fucking nightmare, and even if you manage all that you need to be pumping on it every few meters 24/7 to keep pressures that low with the realistic amount of leaks/in order to be able to pump down the local area where one occurs.

              Like imagine if you needed a phat motor on every block to make roads work. The infrastructure demand is just unreal

    • FelipeFelop@discuss.online
      link
      fedilink
      English
      arrow-up
      4
      ·
      10 months ago

      That makes no sense. It’s been repeatedly tried and failed for very obvious reasons.

      Technically it’s very very hard unless you spend so much it’s uneconomic and takes too long to develop.

      Secondly, its investors who were scammed. Yes they could have done better due diligence but they were still scammed.