8 ms·

The Hyperloop - Not just SF to LA

30 points by dojomouse 13y ago

threeseed 13y ago
Interesting. But still seems to miss all the human elements in the equation. What about if someone is seriously sick can they be evacuated in a reasonable manner ? Likewise what about the inevitable "I need to use the toilet" scenario ?
- dojomouse 13y ago
  They were pretty well done over in the threads for the original posting of the Tesla/SpaceX team's Hyperloop concept on here. I tend to agree with the "it's not that big a deal" sentiment. Usually you're not allowed to go to the toilet for 30min before landing on a commercial jet either. And on a smaller regional jet it's unlikely there's any serious medical help available. Help is only 30min away, and that's assuming you got sick right at the very START of the trip. I think allergic reactions and choking are probably the biggest risks. One to think about, but probably not a reason to write off a game changing transport method! I do think it's funny that the most common question when someone proposes a super efficient super fast transport solution is "How will people go to the toilet?". I guess people who have real trouble can still take the bus or a plane. I'll go before departure, and cross my legs if need be :-)
  - vxNsr 13y ago
    Or do what children do: wear a diaper :P Honestly though, if they would ever expand it to cross country, or like CHI-LA, which would probably be an hour long trip, they better have a break somewhere in Kansas, just because I can't stand to be in such a small enclosed space for very long, trains are great, airplanes, also fine, but something without windows and where I can't stand (if the renders are any indication) is gonna cause problems.
    - dojomouse 13y ago
      I guess that'd be a good way to drive demand for physically isolated Hyperloop seating modules...
    - loceng 13y ago
      I think it could be quite a lovely nap for an hour, or chat with the person next to you, or what not. Just make sure you're not feeling sick beforehand / are in good health..
- RyanZAG 13y ago
  Evacuation seems a very strange problem. You certainly can't be evacuated in under 30 mins when you're half way across the Atlantic ocean in a plane, or half way between SF and LA in a car. Also, max 30 mins is a very short time for medical evacuations which often run into the 2+ hour range for most transport scenarios. Toilet is a minor worry and if it really is such a big deal to you (and other crazies who can't wait 30 minutes), reducing the passenger capacity of a car by 1/3rd so that a toilet can be added is a very simple and obvious solution that just means your ticket price goes up a bit. The toilet's waste could be emptied automatically at each stop in the station. With how much people bring this issue up however, I'm incredibly surprised we have no toilets in buses! You'd think this was the biggest issue to ever hit public transport... No doubt it was left out of the original spec because nobody even considered it worth including. EDIT: Feels like a debate someone must have had when they first started riding horses. "I'm not going to ride up on that horse, what happens if I need to use the toilet? When I'm just walking I just need to bend down in the bushes! Nobody will ever want to ride horses - consider the human implications of being up in the air!"
  - anonymouz 13y ago
    > With how much people bring this issue up however, I'm incredibly surprised we have no toilets in buses! You don't? Pretty much all long distance buses (many hours ride; very few stops, usually clustered at the beginning and the end of the journey) have had toilets on board. Where you can get away without toilets is public transport in cities, and to some degree overland if there are enough stops (though that can be a problem). With a bus there's also always the option of just asking the driver to stop for a couple of minutes if it's really urgent.
    - RyanZAG 13y ago
      Sounds good. When the hyperloop starts being used for many hours long rides, we can add in toilets then. Maybe we can have an option - double ticket price with toilet, or half price without? I have a feeling the double ticket price cars will be empty.
      - 13y ago
- reneherse 13y ago
  Well if people are really worried about the bathroom issue, they can just wear the specially designed, pneumatically sealed "HyperDiaper". Damned if I can't find the link to the appendix of Musk's document where he discussed those specs... Anyway, what's likely more of an issue than either pod or bodily evacuation, is the possibility of motion sickness owing to the lack of a visible steady horizon from inside the capsule (no windows, no transparent aluminum pipes). I suspect this is one of the reasons Musk mentions something about landscape images being displayed on the pod interiors. Some kind of projected artificial horizon, always steady no matter what the orientation of the pod, would likely keep people from getting too loopy. Similarly, the very first subway in NYC (pneumatic, no less) [1] had cars without windows, but the line was only a few hundred feet long, so it's doubtful motion sickness was an issue. [1] http://freetoursbyfoot-nyc.blogspot.com/2013/02/today-in-1870-nycs-first-subway-line.html http://freetoursbyfoot-nyc.blogspot.com/2013/02/today-in-187...
- tptacek 13y ago
  A bigger human problem with the proposal is, apparently, motion sickness. This isn't an abstract issue, like the diaper requirements. The vehicles in this proposal travel 3x faster than HSR; it thus can't use the exact same path as HSR; for instance, it might need much wider curves, which in the mountains might involve substantially more tunneling. Motion sickness is a pragmatic concern for air travel too; it dictates that you want to run routes above the weather.
  - batbomb 13y ago
    It's a in a cylinder. On curves, the acceleration would tilt the cars sideways and acceleration would be, from the viewpoint of a rider, down towards the floor, like gravity (like when a plane banks). Unlike a banking plane, you would maintain vertical acceleration down and have even less weird accelerations than you would in that instance. Your head would experience less jerking around than you would in a fast car ride.
    - tptacek 13y ago
      Here's a mathematician's skeptical take on this issue (just CMD-F "jerk").
      - dojomouse 13y ago
        I think jerk could be kept much lower than in an aircraft though - in the hyperloop jerk would be basically 100% deterministic. You could design to keep it within reasonable limits. Sure, there might be minor imperfections in the tube surface, but there's suspension in the air skis to isolate that. I think the main thing needed to prevent motion sickness would be a virtual 'view' with horizon, which isn't hard to create.
charlieflowers 13y ago
There is literally no discussion on Hacker News about this article (so far) except the discussion about the toilet issue. Sigh.
- Anechoic 13y ago
  The whole problem is this is a proposal. It's not even at the research stage. As such, all we can do is speculate to its advantages and/or disadvantages and a lot of questions go answered. If Musk (or anyone else) wants to address the criticism, that someone needs to build a demonstration systems. This was done for HSR (the US even as a test facility outside Pueblo Colorado for rail research) and MAglev (the now defunct TransRapid facility in Germany, plus a couple of Japanese facilities). Once something has been built that people can observe and ride, a lot of these questions will go away. For know, what else can we do?
  - jared314 13y ago
    Musk said it himself on an earnings call: "I think I kind of shot myself by ever mentioning the hyper loop ... [I] obviously have to focus on core business and SpaceX business and that's more than enough."[0] He had to build Tesla to prove it would work. He had to build SpaceX to prove it would work. I think Musk knew, the moment he first mentioned it, that it would be nothing but endless pedantic discussions about trivialities. [0] http://www.earningsimpact.com/Transcript/82715/TSLA/Q2-2013-Earnings-Call/Page/6 http://www.earningsimpact.com/Transcript/82715/TSLA/Q2-2013-...
- protomyth 13y ago
  I find it a little odd that the toilet issue has more attention than the whole ADA compliance problems.
loudin 13y ago
I think it's worth thinking about how some routes would enjoy increased popularity given the existence of a hyperloop mode of transport. For instance, the Chicago-New York route is roughly 800 miles, which is about an hour of hyperloop time. If the tickets were still priced in the $20 range each way, just think of how many more people would travel between the two cities. People could live in Chicago while commuting to work in NYC. Others could live in NYC and impulsively decide to travel to Chicago for a fun night out on the town. Surely, the route would increase in popularity - perhaps vastly so. What I love about the hyperloop is that it's like a physical embodiment of the internet - shrinking the geographical distance that separates us.
- tptacek 13y ago
  Not that a "hyperloop" is ever going to happen anywhere, but: * There won't be $20-40 tickets on the SF/LA route, because (a) capex costs will be much higher than the white paper anticipates (it costs its el line at 1/10th the going rate for viaducts and its tunnel at a tiny fraction of any other tunnel, even given the narrower tube --- not to mention an extremely optimistic projection for much much tunneling will be required, projections lower than those for the Tejon Pass HSR concept, which runs at 1/3rd the speed or less and can thus follow a tighter course) and (b) ticket prices have to account for opex as well, which will be substantial; having built the thing, it does not simply run itself. * Land in the central valley might be cheap, but the ROWs you'll need to do anything from Chicago to NYC won't be anything resembling cheap. Note that the "hyperloop" painfully acknowledges this, by terminating in Sylmar, on the far northern outskirts of LA, because integrating more thoughtfully with LA's transit system would have been prohibitively expensive; similarly, the "SF" end of the route is actually San Leandro, which is an hour easy from SF in traffic.
  - Spooky23 13y ago
    The interstate ROW were held up as a possible solution -- I say good luck there. I've seen a half dozen projects try to use, cross or borrow interstate rights of way. You'd probably need a $1B of waters and lobbyists just to make that happen.
  - 13y ago
kornork 13y ago
I think the killer route for the hyperloop is Los Angeles to Las Vegas. Las Vegas could pay for it - sidestepping California's budget issues. In return they would get a giant vacuum cleaner nozzle for gamblers from southern California.
- dghughes 13y ago
  Hasn't there been some sort of train route proposed for decades? A friend went to Las Vegas a few years ago and said condos are sold along a proposed high speed train route but it's always "just a few years from completion".
  - Anechoic 13y ago
    There is (was?) a privately-funded project that was well into the engineering phase (http://www.xpresswest.com http://www.xpresswest.com) but they needed a Federal loan to make the project feasible and FRA recently put the kibosh on the loan: http://www.reviewjournal.com/transportation-insider/prospects-dim-high-speed-rail-link-la-vegas http://www.reviewjournal.com/transportation-insider/prospect...
    - dojomouse 13y ago
      There have been several proposals I think. Last I heard it was dead. The problem is that it kind of sucks as a commercial proposition. A Hyperloop solution, on the other hand, wouldn't. I've done a basic profitability analysis on the route, will publish as soon as I can bloggify it. Basically, even with the existing air traffic only, it's a really attractive route, especially if you link it in to an SF-LA Hyperloop as well and hence capture the SF-LasVegas air traffic too. The main problem with the xpresswest train is that it basically went from nowhere to nowhere. Still needed a car at both ends. That and its being grossly expensive.
bastawhiz 13y ago
To address the braking concern: the author of the article says that the Hyperloop stops and starts at 0.5g, which would make it take 60 seconds to stop. That's not entirely true. 0.5g is the acceleration that the pods would experience under normal circumstances. Everyone reading this (unless they're on the ISS or flying a plane in a sine curve) is presently experiencing 1G, give or take a tiny bit. 2G is felt by lots of people on a day-to-day basis during normal activities. Some rollercoasters get up to 4.5G. Astronauts train at very high G. If there's a catastrophic failure, the hyperloop could slow down at much higher Gs (some informal calculations says between 5 and 6 Gs wouldn't be unreasonable). If 0.5G is 60 seconds, 5G is well under ten seconds. Pods spaced 30 seconds apart would have plenty of time to stop. Some might say, "But 4+ Gs can cause an untrained person to black out!" Yeah, and you're on a hyperloop traveling 750+MPH that's just experienced catastrophic failure. And the scenario that is being explored involves either the tube in front of you having been obliterated, the pod in front of yours having come to a complete halt instantly, or someone dropped a blue shell. To address the pod loading/unloading issue: stations are not located along the main track, they happen at branches. Proper timing means that branched stations can be bypassed, allowing pods to bypass the station ("nonstop" pods, if you will) without shortening or lengthening delays for pods at the station. This means that when a station diverts a pod, it creates a 60 second gap instead of two 30 second gaps. Another station further down the line could then fill that gap with a train that had arrived earlier. This means that pods could load/unload much more slowly than if they were forced to arrive/depart in the order that they passed through the vicinity of a station. And pods that are not stopping at a station would experience no delay. Main stations ("terminal stations") could have a buffer of pods. If it takes granny five minutes to get off the pod, who cares? Just put a different pod in the queue for departure. Order shouldn't matter, you're at the end of the line. Ever been on MUNI and seen the inbound trains show up on the outbound tracks in a different order? Exactly. To address the time comparison between the hyperloop and HSR: this is completely speculative, but it's doubtful that the HSR could achieve its proposed time of 2:48. The author talks about this like it's a hard fact. I'd be surprised if HSR could hit three hours, or even four. Has this guy ridden on Caltrain? The sheer number of delays is startling. Hyperloop, OTOH, is decidedly much more reliable since the tube is sealed. Nothing can get in the way of the tube, cars can't collide with pods, it doesn't matter what the weather is, etc. Even if the Hyperloop doesn't meet its 30-40 minute target, I think it would be much more reliable than HSR, and there's room for it to improve as well as the technology improves.
dnautics 13y ago
the math in this article is wrong, they are comparing the "capacity" of the CHSR. There is no way the CHSR is going to be operating at capacity. Operating at 10% is a more likely scenario. Moreover, direct from LA to SF is a feature, not a bug. I might take the CHSR IF it only went between the two cities, having extra stops makes it LESS likely that I will use it (currently at zero likelihood; I'd rather just take a plane).
- dojomouse 13y ago
  Do you mean the article submitted here? I don't think I mentioned the CHSR or Hyperloop capacity.
  - dnautics 13y ago
    Ugh, I posted to the wrong hyperloop article. Sorry.
    - dojomouse 13y ago
      No worries. I hadn't even seen the other article - you did me a favour.
JDDunn9 13y ago
It still seems like ET3 has a much better design. It's simpler, more efficient, faster, and has fewer moving parts (that can break). The only down-side would be the 6% royalty you'd have to pay. As far as proposed routes, train stations would be a better marker than air travel (to eliminate trips over water and mountains, etc.) In which case Japan would dominate with 45 of the 51 busiest stations in the world. The top trip on his chart has 10 million travelers a year, Shinjuku station sees 1.25 billion. http://www.japantoday.com/category/travel/view/the-51-busiest-train-stations-in-the-world-all-but-6-located-in-japan http://www.japantoday.com/category/travel/view/the-51-busies...
- dojomouse 13y ago
  I prefer many elements of the ET3 design. The problem is that it's not really moving. The 6% royalty is kind of ludicrous given the amount of work that's gone into it - if someone made a single line then ET3 would get billions of dollars. I have talked to Daryl Oster several times and think he is a great guy and really honest advocate of the ET3 system, but I think the ET3 membership model probably isn't encouraging 'big business' participation, and the patent (while probably not that hard to work around) could be reducing interest from other areas. That said, I don't know what stage things are at in China. There was certainly some active research there. Another big benefit of an ET3 type system that you don't mention is the tube fill factor. In ET3 you can take up basically the whole tube, because there's so little air that you don't need to worry about the Kantrowitz limit (I think). In Hyperloop, you can only take up 30%. This means that ET3 can either have much smaller tubes (big cost saving) or much larger capsules (same cost... but TOILETS!!! ;-)).

30 points by dojomouse 13y ago

Interesting. But still seems to miss all the human elements in the equation. What about if someone is seriously sick can they be evacuated in a reasonable manner ? Likewise what about the inevitable "I need to use the toilet" scenario ?

dojomouse 13y ago
They were pretty well done over in the threads for the original posting of the Tesla/SpaceX team's Hyperloop concept on here. I tend to agree with the "it's not that big a deal" sentiment. Usually you're not allowed to go to the toilet for 30min before landing on a commercial jet either. And on a smaller regional jet it's unlikely there's any serious medical help available. Help is only 30min away, and that's assuming you got sick right at the very START of the trip. I think allergic reactions and choking are probably the biggest risks. One to think about, but probably not a reason to write off a game changing transport method! I do think it's funny that the most common question when someone proposes a super efficient super fast transport solution is "How will people go to the toilet?". I guess people who have real trouble can still take the bus or a plane. I'll go before departure, and cross my legs if need be :-)
- vxNsr 13y ago
  Or do what children do: wear a diaper :P Honestly though, if they would ever expand it to cross country, or like CHI-LA, which would probably be an hour long trip, they better have a break somewhere in Kansas, just because I can't stand to be in such a small enclosed space for very long, trains are great, airplanes, also fine, but something without windows and where I can't stand (if the renders are any indication) is gonna cause problems.
  - dojomouse 13y ago
    I guess that'd be a good way to drive demand for physically isolated Hyperloop seating modules...
  - loceng 13y ago
    I think it could be quite a lovely nap for an hour, or chat with the person next to you, or what not. Just make sure you're not feeling sick beforehand / are in good health..
RyanZAG 13y ago
Evacuation seems a very strange problem. You certainly can't be evacuated in under 30 mins when you're half way across the Atlantic ocean in a plane, or half way between SF and LA in a car. Also, max 30 mins is a very short time for medical evacuations which often run into the 2+ hour range for most transport scenarios. Toilet is a minor worry and if it really is such a big deal to you (and other crazies who can't wait 30 minutes), reducing the passenger capacity of a car by 1/3rd so that a toilet can be added is a very simple and obvious solution that just means your ticket price goes up a bit. The toilet's waste could be emptied automatically at each stop in the station. With how much people bring this issue up however, I'm incredibly surprised we have no toilets in buses! You'd think this was the biggest issue to ever hit public transport... No doubt it was left out of the original spec because nobody even considered it worth including. EDIT: Feels like a debate someone must have had when they first started riding horses. "I'm not going to ride up on that horse, what happens if I need to use the toilet? When I'm just walking I just need to bend down in the bushes! Nobody will ever want to ride horses - consider the human implications of being up in the air!"
- anonymouz 13y ago
  > With how much people bring this issue up however, I'm incredibly surprised we have no toilets in buses! You don't? Pretty much all long distance buses (many hours ride; very few stops, usually clustered at the beginning and the end of the journey) have had toilets on board. Where you can get away without toilets is public transport in cities, and to some degree overland if there are enough stops (though that can be a problem). With a bus there's also always the option of just asking the driver to stop for a couple of minutes if it's really urgent.
  - RyanZAG 13y ago
    Sounds good. When the hyperloop starts being used for many hours long rides, we can add in toilets then. Maybe we can have an option - double ticket price with toilet, or half price without? I have a feeling the double ticket price cars will be empty.
    - 13y ago
reneherse 13y ago
Well if people are really worried about the bathroom issue, they can just wear the specially designed, pneumatically sealed "HyperDiaper". Damned if I can't find the link to the appendix of Musk's document where he discussed those specs... Anyway, what's likely more of an issue than either pod or bodily evacuation, is the possibility of motion sickness owing to the lack of a visible steady horizon from inside the capsule (no windows, no transparent aluminum pipes). I suspect this is one of the reasons Musk mentions something about landscape images being displayed on the pod interiors. Some kind of projected artificial horizon, always steady no matter what the orientation of the pod, would likely keep people from getting too loopy. Similarly, the very first subway in NYC (pneumatic, no less) [1] had cars without windows, but the line was only a few hundred feet long, so it's doubtful motion sickness was an issue. [1] http://freetoursbyfoot-nyc.blogspot.com/2013/02/today-in-1870-nycs-first-subway-line.html http://freetoursbyfoot-nyc.blogspot.com/2013/02/today-in-187...
tptacek 13y ago
A bigger human problem with the proposal is, apparently, motion sickness. This isn't an abstract issue, like the diaper requirements. The vehicles in this proposal travel 3x faster than HSR; it thus can't use the exact same path as HSR; for instance, it might need much wider curves, which in the mountains might involve substantially more tunneling. Motion sickness is a pragmatic concern for air travel too; it dictates that you want to run routes above the weather.
- batbomb 13y ago
  It's a in a cylinder. On curves, the acceleration would tilt the cars sideways and acceleration would be, from the viewpoint of a rider, down towards the floor, like gravity (like when a plane banks). Unlike a banking plane, you would maintain vertical acceleration down and have even less weird accelerations than you would in that instance. Your head would experience less jerking around than you would in a fast car ride.
  - tptacek 13y ago
    Here's a mathematician's skeptical take on this issue (just CMD-F "jerk").
    - dojomouse 13y ago
      I think jerk could be kept much lower than in an aircraft though - in the hyperloop jerk would be basically 100% deterministic. You could design to keep it within reasonable limits. Sure, there might be minor imperfections in the tube surface, but there's suspension in the air skis to isolate that. I think the main thing needed to prevent motion sickness would be a virtual 'view' with horizon, which isn't hard to create.

charlieflowers 13y ago

There is literally no discussion on Hacker News about this article (so far) except the discussion about the toilet issue. Sigh.

Anechoic 13y ago
The whole problem is this is a proposal. It's not even at the research stage. As such, all we can do is speculate to its advantages and/or disadvantages and a lot of questions go answered. If Musk (or anyone else) wants to address the criticism, that someone needs to build a demonstration systems. This was done for HSR (the US even as a test facility outside Pueblo Colorado for rail research) and MAglev (the now defunct TransRapid facility in Germany, plus a couple of Japanese facilities). Once something has been built that people can observe and ride, a lot of these questions will go away. For know, what else can we do?
- jared314 13y ago
  Musk said it himself on an earnings call: "I think I kind of shot myself by ever mentioning the hyper loop ... [I] obviously have to focus on core business and SpaceX business and that's more than enough."[0] He had to build Tesla to prove it would work. He had to build SpaceX to prove it would work. I think Musk knew, the moment he first mentioned it, that it would be nothing but endless pedantic discussions about trivialities. [0] http://www.earningsimpact.com/Transcript/82715/TSLA/Q2-2013-Earnings-Call/Page/6 http://www.earningsimpact.com/Transcript/82715/TSLA/Q2-2013-...
protomyth 13y ago
I find it a little odd that the toilet issue has more attention than the whole ADA compliance problems.

loudin 13y ago

I think it's worth thinking about how some routes would enjoy increased popularity given the existence of a hyperloop mode of transport. For instance, the Chicago-New York route is roughly 800 miles, which is about an hour of hyperloop time. If the tickets were still priced in the $20 range each way, just think of how many more people would travel between the two cities. People could live in Chicago while commuting to work in NYC. Others could live in NYC and impulsively decide to travel to Chicago for a fun night out on the town. Surely, the route would increase in popularity - perhaps vastly so. What I love about the hyperloop is that it's like a physical embodiment of the internet - shrinking the geographical distance that separates us.

tptacek 13y ago
Not that a "hyperloop" is ever going to happen anywhere, but: * There won't be $20-40 tickets on the SF/LA route, because (a) capex costs will be much higher than the white paper anticipates (it costs its el line at 1/10th the going rate for viaducts and its tunnel at a tiny fraction of any other tunnel, even given the narrower tube --- not to mention an extremely optimistic projection for much much tunneling will be required, projections lower than those for the Tejon Pass HSR concept, which runs at 1/3rd the speed or less and can thus follow a tighter course) and (b) ticket prices have to account for opex as well, which will be substantial; having built the thing, it does not simply run itself. * Land in the central valley might be cheap, but the ROWs you'll need to do anything from Chicago to NYC won't be anything resembling cheap. Note that the "hyperloop" painfully acknowledges this, by terminating in Sylmar, on the far northern outskirts of LA, because integrating more thoughtfully with LA's transit system would have been prohibitively expensive; similarly, the "SF" end of the route is actually San Leandro, which is an hour easy from SF in traffic.
- Spooky23 13y ago
  The interstate ROW were held up as a possible solution -- I say good luck there. I've seen a half dozen projects try to use, cross or borrow interstate rights of way. You'd probably need a $1B of waters and lobbyists just to make that happen.
- 13y ago

kornork 13y ago

I think the killer route for the hyperloop is Los Angeles to Las Vegas. Las Vegas could pay for it - sidestepping California's budget issues. In return they would get a giant vacuum cleaner nozzle for gamblers from southern California.

dghughes 13y ago
Hasn't there been some sort of train route proposed for decades? A friend went to Las Vegas a few years ago and said condos are sold along a proposed high speed train route but it's always "just a few years from completion".
- Anechoic 13y ago
  There is (was?) a privately-funded project that was well into the engineering phase (http://www.xpresswest.com http://www.xpresswest.com) but they needed a Federal loan to make the project feasible and FRA recently put the kibosh on the loan: http://www.reviewjournal.com/transportation-insider/prospects-dim-high-speed-rail-link-la-vegas http://www.reviewjournal.com/transportation-insider/prospect...
  - dojomouse 13y ago
    There have been several proposals I think. Last I heard it was dead. The problem is that it kind of sucks as a commercial proposition. A Hyperloop solution, on the other hand, wouldn't. I've done a basic profitability analysis on the route, will publish as soon as I can bloggify it. Basically, even with the existing air traffic only, it's a really attractive route, especially if you link it in to an SF-LA Hyperloop as well and hence capture the SF-LasVegas air traffic too. The main problem with the xpresswest train is that it basically went from nowhere to nowhere. Still needed a car at both ends. That and its being grossly expensive.

bastawhiz 13y ago

To address the braking concern: the author of the article says that the Hyperloop stops and starts at 0.5g, which would make it take 60 seconds to stop. That's not entirely true. 0.5g is the acceleration that the pods would experience under normal circumstances. Everyone reading this (unless they're on the ISS or flying a plane in a sine curve) is presently experiencing 1G, give or take a tiny bit. 2G is felt by lots of people on a day-to-day basis during normal activities. Some rollercoasters get up to 4.5G. Astronauts train at very high G. If there's a catastrophic failure, the hyperloop could slow down at much higher Gs (some informal calculations says between 5 and 6 Gs wouldn't be unreasonable). If 0.5G is 60 seconds, 5G is well under ten seconds. Pods spaced 30 seconds apart would have plenty of time to stop. Some might say, "But 4+ Gs can cause an untrained person to black out!" Yeah, and you're on a hyperloop traveling 750+MPH that's just experienced catastrophic failure. And the scenario that is being explored involves either the tube in front of you having been obliterated, the pod in front of yours having come to a complete halt instantly, or someone dropped a blue shell. To address the pod loading/unloading issue: stations are not located along the main track, they happen at branches. Proper timing means that branched stations can be bypassed, allowing pods to bypass the station ("nonstop" pods, if you will) without shortening or lengthening delays for pods at the station. This means that when a station diverts a pod, it creates a 60 second gap instead of two 30 second gaps. Another station further down the line could then fill that gap with a train that had arrived earlier. This means that pods could load/unload much more slowly than if they were forced to arrive/depart in the order that they passed through the vicinity of a station. And pods that are not stopping at a station would experience no delay. Main stations ("terminal stations") could have a buffer of pods. If it takes granny five minutes to get off the pod, who cares? Just put a different pod in the queue for departure. Order shouldn't matter, you're at the end of the line. Ever been on MUNI and seen the inbound trains show up on the outbound tracks in a different order? Exactly. To address the time comparison between the hyperloop and HSR: this is completely speculative, but it's doubtful that the HSR could achieve its proposed time of 2:48. The author talks about this like it's a hard fact. I'd be surprised if HSR could hit three hours, or even four. Has this guy ridden on Caltrain? The sheer number of delays is startling. Hyperloop, OTOH, is decidedly much more reliable since the tube is sealed. Nothing can get in the way of the tube, cars can't collide with pods, it doesn't matter what the weather is, etc. Even if the Hyperloop doesn't meet its 30-40 minute target, I think it would be much more reliable than HSR, and there's room for it to improve as well as the technology improves.

dnautics 13y ago

the math in this article is wrong, they are comparing the "capacity" of the CHSR. There is no way the CHSR is going to be operating at capacity. Operating at 10% is a more likely scenario. Moreover, direct from LA to SF is a feature, not a bug. I might take the CHSR IF it only went between the two cities, having extra stops makes it LESS likely that I will use it (currently at zero likelihood; I'd rather just take a plane).

dojomouse 13y ago
Do you mean the article submitted here? I don't think I mentioned the CHSR or Hyperloop capacity.
- dnautics 13y ago
  Ugh, I posted to the wrong hyperloop article. Sorry.
  - dojomouse 13y ago
    No worries. I hadn't even seen the other article - you did me a favour.

JDDunn9 13y ago

It still seems like ET3 has a much better design. It's simpler, more efficient, faster, and has fewer moving parts (that can break). The only down-side would be the 6% royalty you'd have to pay. As far as proposed routes, train stations would be a better marker than air travel (to eliminate trips over water and mountains, etc.) In which case Japan would dominate with 45 of the 51 busiest stations in the world. The top trip on his chart has 10 million travelers a year, Shinjuku station sees 1.25 billion. http://www.japantoday.com/category/travel/view/the-51-busiest-train-stations-in-the-world-all-but-6-located-in-japan http://www.japantoday.com/category/travel/view/the-51-busies...

dojomouse 13y ago
I prefer many elements of the ET3 design. The problem is that it's not really moving. The 6% royalty is kind of ludicrous given the amount of work that's gone into it - if someone made a single line then ET3 would get billions of dollars. I have talked to Daryl Oster several times and think he is a great guy and really honest advocate of the ET3 system, but I think the ET3 membership model probably isn't encouraging 'big business' participation, and the patent (while probably not that hard to work around) could be reducing interest from other areas. That said, I don't know what stage things are at in China. There was certainly some active research there. Another big benefit of an ET3 type system that you don't mention is the tube fill factor. In ET3 you can take up basically the whole tube, because there's so little air that you don't need to worry about the Kantrowitz limit (I think). In Hyperloop, you can only take up 30%. This means that ET3 can either have much smaller tubes (big cost saving) or much larger capsules (same cost... but TOILETS!!! ;-)).