5 ms·

German here. ICE sucks majorly. ICE is engineered way over the limitations of the underlying technology. They break down easily and are constantly late. I'd t

• himinlomax 6y ago
  TGV runs very well, except for the weekly labor dispute that's completely orthogonal to the fact that it's not running in a vacuum. How you people believe the risk of explosive decompression will solve whatever problems a minority of high speed train systems have is beyond me.
  • j-pb 6y ago
    1 bar is acutally not that bad. Hyoerloop pods are smaller, so less lives are at risk. And most importantly of all. It's not gonna be explosive, unless you rip the thing open with a bomb and you're right next to it. Even if you rip the tube in half, the air is going to take some time to fill it up. A few miles from the hole there will be a much more harmless pressure gradient already. Sure it might shake your capsule, but you're not gonna get shredded.
    • jankotek 6y ago
      Pressure wave moves at speed of sound. Lightweigh capsule gets destroyed just by derailing at 500mph. Any bad event will put down ALL trains on track. And rescuing people trapped in 100 miles long steel pipe... Hyperloop is a nightmare!
      • j-pb 6y ago
        See my above reply. Speed of sound doesn't mean much if there is a constantly softening gradient. https://en.m.wikipedia.org/wiki/Hagen%E2%80%93Poiseuille_equation#Poiseuille's_equation_for_an_ideal_isothermal_gas https://en.m.wikipedia.org/wiki/Hagen%E2%80%93Poiseuille_equ... Edit: To give a good analogy: Electricity also travels at the speed of light through a cable, however due to resistance you will get different current reading depending on where you measure.
    • tjpnz 6y ago
      >And most importantly of all. It's not gonna be explosive, unless you rip the thing open with a bomb and you're right next to it. And that's precisely what makes it unworkable with regards to safety. Burying the tubes is an option but by that point you would be looking at rail instead.
      • j-pb 6y ago
        Ok so somebody attacks it, with explosives. And manages to time them well enough that they go off right next to a cart, or inside one. They will get 1 passenger car. Which is what? 8 People? The tube will slowly fill with air, everybody else evacuates safely at a slower speed. I'm willing to bet on those odds. Compared to the number of car accidents, it'a a no brainer.
    • himinlomax 6y ago
      > 1 bar is acutally not that bad. That does not mean anything. The weight of a 1 cm² column of air is 1 kg. So 1 ton for 1 m². Let's say a square profile hyperloop tunnel 1 m high decompressing will be the equivalent of dropping one tonne for each meter. The shock will propagate at the speed of sound.
      • j-pb 6y ago
        You neglect the friction that even laminar flow would experience while flowing into the tube. If you make small fins at the top of the tube you can even exagerate the effect and introduce turbulence, which further reduces flow rate. There is a reason why pipelines need pumping stations every couple miles, to keep the fluid at speed. Sure the wave might propagate at the speed of sound but that doesn't matter much if its pressure gradient is slow enough. https://en.m.wikipedia.org/wiki/Hagen–Poiseuille_equation#Poiseuille's_equation_for_an_ideal_isothermal_gas https://en.m.wikipedia.org/wiki/Hagen–Poiseuille_equation#Po... Edit: To give a good analogy: Electricity also travels at the speed of light through a cable, however due to resistance you will get different current reading depending on where you measure. Edit2: I reread your argument, and there is also a flaw in your energy calculation. The energy per time is not proportional to the length of the tunnel, but proportional to the size of the inlet. Your calculation would be if you remove the entire top of the tunnel at once, over it's entire length.
        • himinlomax 6y ago
          Turbulence in a near vacuum? I'm more than rusty on my statistical mechanics, but what you describe will only matter long after most of the potential energy has done its damage.
          • j-pb 6y ago
            Don't look at the wavefront of the first 100m, the pod there is gone anyways in case of a bomb. Turbulence on the phase of what comes after the near vacuum. The plug essentially plugs itself from resticted airflow. If you want to be extra safe you could even add small tesla valve style fins around the border of the tube, to increase turbulence.
• ginko 6y ago
  That's a problem of the ICE not HSR as a whole. I never had issues with the TGV or shinkansen. DB is a joke in general. Any time I travel through Germany there's been constant delays.
  • LittlePeter 6y ago
    I too have bad experience traveling Basel - Cologne route with DB. At this point, I switched to flying or renting a car. The thought of traveling with DB gives me shudders.
• matthewmacleod 6y ago
  I'd take a hyperloop over an ICE any time. Since a “hyperloop” doesn’t exist and you have no basis for understanding what the tradeoffs are, this is not very convincing. The point remains - high-speed rail is a known and deliverable system. Good implementations exist in several countries. In contrast, a new technology comes with associated engineering and economic challenges, and it’s unclear how those can solve the existing problems that high-sped rail deals with.
  • j-pb 6y ago
    Ok let me rephrase, and actually make my point stronger. I'd take a shot at fully funding hyperloop with all the ressources that our current HSR system has, over keeping our ICEs any day. If it was up to me we'd fund Transrapid. It's also build on pylons, does 500kmh, and is proven tech that has been running for 40 years. So we get the best of both. But I don't see a future for Transrapid, because it's not cool enough for political backing. Hyperloop is, so I'm doing a strategic vote here.
    • himinlomax 6y ago
      Do TGV and Shinkansen have the problems you say ICE has? Do they run in a literal vacuum?
    • deng 6y ago
      The Transrapid was simply way too expensive. The planned route between Hamburg and Berlin, which is not even 300km, was shelved because the estimated costs exploded. The DB (German Railway) gets 2.5 billion EUR funding per year for its train network, which is 38.500km, so it's really not that much. The Transrapid wouldn't even have been significantly faster, since there were three stops planned between Hamburg and Berlin. And both the Transrapid and the ICE were/are built by Siemens, so there's not reason to think they would have been more reliable.
      • Xylakant 6y ago
        To add to that, one of the major problems was that due to the political power structure (state vs federal government etc.), a no-stop trip on the direct route wasn’t viable political. So the DB basically opted for refurbishing the existing track, because that did not need political approval on any level - the track existed and no new permits were required. All of this would be issues that hyperloop would have to face as well. None of these are in any way related to the underlying technology. In addition, there’s extremely few routes in germany where 300km/h vs. 500km/h top speed makes a significant difference. The latest generation of ICE trains trades a lower top speed for faster acceleration. We’re a small country with comparatively short distances between population centers.
• detaro 6y ago
  > I'd pour all of our subsidies for Deutsche Bahn into it in a heartbeat. congratulations, you just got a few high-speed links between half a dozen cities at the cost of rail infrastructure for the rest of the country (a large part of the subsidies goes into boring regional services). The answer to "our rail infrastructure should be better maintained" is not "dump all the money in shiny unproven high-tech".
• innocenat 6y ago
  Instead of hyperloop, why not Japan SCMagLev? That things is actually getting build for commercial operation right now.
• Xylakant 6y ago
  German here. ICE rocks. Until like 2 years ago, I used to travel long distance nearly every week, often all the way across germany. The problem is not the ICE or high speed rail connectivity, the problems arise at the edges, when you need to switch over and travel the last few miles. For example, I used to travel from Berlin to Hamburg for on-site work. The leg from Berlin to Hamburg was faster than the connection from Hamburg Main to the client site. Certainly, there’s delays, but I’ve done the same trip by car and it constantly took longer than by train, I had very few trips where I didn’t end up caught in a traffic jam somewhere on the autobahn. There’s a bit of a perception problem: nobody notices if you’re late by five minutes if traveling by car because no one has such an exact expectation for car travel. Delays in train travel also have a problem that is exacerbated by the timetables of the DB: In an attempt to make travel times seem shorter, there’s often insufficient buffer at places where you need to change, so that a few minutes of delay will result in an hour of layover. Combine that with lack of maintenance on the rails and you get unfavorable results. None of the problems would be solved by hyper loop or any other technology. It’s a result of misaligned incentives. Still, with all the things wrong in planning, maintenance and political incentives around it, high speed rail still is the best way to travel medium and long distance.
  • j-pb 6y ago
    You neglect the timing advantages gained from smaller independent crafts. Hyperloop has the ability to essentially do driverless packet routing. You can't do that with high speed rail.
    • masswerk 6y ago
      For safety concerns, you'd probably have to divide the route into air-locked sections with a pod per block. This gives you about one packet every 25 miles or so – and rather slow packet routing (more like RFC 1149 – https://tools.ietf.org/html/rfc1149 https://tools.ietf.org/html/rfc1149 )
      • j-pb 6y ago
        At 1200km/h thats one every 2 minutes per 40km (25miles). So you get 30 pods per hour. With 28 passengers each. Which is 840 passengers per hour. Compared with the different ICE 4 models, even the Largest ICE transports less passengers per hour. 499 (K1n) 724 (K3s, 10-car) 830 (K3, 12-car) Sure, you might say that those are only the planned stats for the hyperloop. But even halfed it's still competitive due to speed alone. Furthermore ICE trains are half empty most of the time, even when it's packed. Why? Because DB insists on having 18th century style 1st and 2nd class tickets. And most people can't afford that. However hyperloop has no such distinction, because all the pods can be made to "first class standards" due to the direct point A to point B routing nature. Alternstively, the richt people have to wait until their pod is at capacty, which I'd be delighted to see. So in reality ICE capacity is probably half of what hyperloop could provide. Edit: I'm using the assumption of 1 ICE per hour, because that's how the entire german train system is sheduled. And we're comparing Hyperloop to the current system.
• rwmj 6y ago
  The Shinkansen is an existence proof that high speed rail can be fast, comfortable, and always on time (and while by no means cheap, affordable for many). I often wonder what Japan did uniquely that makes this possible. But building trains that run in a vacuum doesn't appear to be a necessary attribute of running a successful high speed rail service.
  • DiogenesKynikos 6y ago
    The was a CCC talk about why the Deutsche Bahn has so many delays: [1]. It turns out that East Germany has great on-time performance, probably because all the infrastructure is new. But overall, Germany has to invest more in upkeep of its existing infrastructure. 1. https://youtu.be/AGCmPLWZKd8 https://youtu.be/AGCmPLWZKd8
• willyt 6y ago
  I think the point is that if your country can’t make it work, perhaps you should look at how the French and the Japanese do it and copy them.