• kerrigan778@lemmy.blahaj.zone
      link
      fedilink
      English
      arrow-up
      9
      ·
      3 days ago

      Only 2 seconds of horizontal g? Not unless they weren’t securely against the seat and died due to blunt force trauma from being slammed into the seat back.

      • scarabic@lemmy.world
        link
        fedilink
        English
        arrow-up
        1
        ·
        3 days ago

        Well now we need to design the train with all seats facing forward and restraints to keep people in place, and we need to have staff abord to do do a safety check that everyone is seated and strapped in before we can get those 2 seconds of theoretically-survivable acceleration.

        Come on. This is cool from an engineering perspective but will never be used on an actual passenger train.

        • AngryCommieKender@lemmy.world
          link
          fedilink
          arrow-up
          2
          ·
          2 days ago

          That test sled doesn’t have the mass of a train car, let alone a full consist. It may very well be used on real trains, just not with such impressive results.

          • scarabic@lemmy.world
            link
            fedilink
            English
            arrow-up
            2
            ·
            3 days ago

            It’s completely not practical.

            7Gs is, granted, not categorically lethal hut average people will start to pass out around 4Gs if the acceleration is vertical, and 9 is about the upper limit that trained, fit Air Force pilots can experience without losing consciousness.

            So 7 is nothing to sneeze at even under ideal conditions.

            • kerrigan778@lemmy.blahaj.zone
              link
              fedilink
              English
              arrow-up
              2
              ·
              3 days ago

              Okay, again, I agree this is not in the slightest practical, but also, again, a train accelerating is not vertical g, horizontal g tolerance is much, much higher than vertical g tolerance, especially “eyeballs in” and it increases greatly the less time it is for. Some early experiments showed untrained people could handle around 20g for less than 10 seconds. Also blunt force risks could be mediated almost completely by ramping the acceleration slowly, first reminding people to brace, then gently forcing them back in their seats. Again, ludicrous, nothing designed for comfort of human passengers is ever going to be designed to accelerate anywhere near that quickly and it’s completely unnecessary anyways.

      • Dr. Moose@lemmy.world
        link
        fedilink
        English
        arrow-up
        6
        ·
        3 days ago

        As other commenter pointer out direction of force is important. Horizontal force is much less dangerous as it doesn’t drain your brain of blood as much as a vertical one. If I recall correctly humans can survive 20-40 Gs of horizontal force compared to just 5-9 of vertical.