Maglev in a tube is a proven technology at full train scale. Here's the Chuo Maglev from the inside.[1] 500KPH in tunnels. They're not pumping down the tunnels, just plowing through on sheer power and money.
The Chuo Maglev makes the Hyperloop One look like a toy project. Watch the video. They have a production-quality train, with tourists and whiny kids riding it, going 500km/h. They've hit 603km/h in tests, but don't run it that hard normally. This is the first section of track between Tokyo and Osaka via Nagoya. Planned opening to Nagoya is 2027. Japan's Alps are in the way. They're tunneling straight through. Longest tunnel segment is 25km and it's being drilled now. 90% of the Tokyo-Nagoya segment will be in tunnel. Stations in Tokyo and Nagoya are under construction. The line will probably run 3-4 trains an hour each way, like the existing Shinkansen.
Hyperloop potentially has a higher speed to 900-1200km/h, but that may not be achieved in practice. The Chuo Shinkansen has a turn radius of 8km, and passengers don't have to be strapped in. Hyperloop would need 4x the radius to go twice as fast with the same ride quality. Laying out a route with a 24km turn radius severely limits where track can go.
Strapping everybody in and pulling 0.5G sustained is not going to go over with customers. Commercial aircraft usually stay within +-0.25G. Maybe 0.5G in mild turbulence, and customers don't like it.
- longitudinal, predictable acceleration, where you can safely tell people to stay in their seats and all will be fine, I’m quite confident most humans would be comfortable with 1G horizontal that adds up to 1.5G diagonal: that’s basically a roller-coaster; it’s not too bad if you ease people into it, i.e. you minimise the jerk;
- lateral, predictable acceleration, like one would expect in turns: not familiar with train technology enough to know if you could adapt pendular train to MagLev, but it seems like a simple enough hack to increase comfort significantly;
- vibrations and turbulences: seem unlikely in a tube on rails, without a train coming in the opposite direction. Those definitely, customers don’t like.
Lateral acceleration is much more annoying to deal with than longitudinal or vertical, even if it's constant. Perhaps they could tilt in bends to convert some of that lateral to vertical?
Our local trains have cars that can lean a bit on their own. Bank the track a bit, lean the car as needed, the humans on board don't recognize a turn unless they're watching intently out the window.
Also, the リニア will cut travel time between Tokyo and Nagoya from about 100 minutes to 40 minutes, which is a big difference for people who do business between those two regions.
That's insane. If you didn't have to switch trains for Philly (30th St) to NYC, an avg ride could take a bit than 100 min if there are only around 7 stops the entire way (normal stops would make the ride like 2 hours). Reducing those numbers by more than half would be incredible. Even if this is just a pipe dream and there isn't a direct train between the two cities right now anyway.
Stops and waiting are by far the biggest slowdown in train travel. In a moderately dense area, if you could magically put enough trains on the tracks to offer all important connections as high frequency point to point connections, you would get enormous improvements in travel time even at moderate cruise speed. Tracks are empty almost all the time because trains cannot evade and have very low deceleration, they have to reliably coordinate far beyond visual range. And by reliably I mean more than aviation grade reliability, because there would be no redundancy and no Hudson River to splash into when you mess up that part.
The good news is that it's "just" an information problem (well, so is landing a rocket, in a way), the bad news is that the number of possible endpoint pairs in a network is bloody high.
In the end you get back to the old vision of on demand "pods". I suppose that those could still be made "rail-efficient" if you make them robotically jack into a paceline behind a tender that provides drafting and power grabbed from an overhead line (you would not want this per pod), but run on battery power only to get to/from the tender at endpoints (which the tender and its followers passes non-stop) and when the paceline gets broken by someone exiting. If you can start over on a new right of way, this is what you should do (in a pinch, you could also take over the leftmost lane of existing roads, but that's not a good place for doing construction and maintenance).
I think you can get most of the benefits just from a well designed timetable. I get the impression that's mostly how they make it work so well in Japan.
There tend to be at least local and express services on almost all routes, and often multiple tiers of express. Another common pattern I've seen is having several commuter services which each run stopping for a different section of the route, and then run express to the central stations. This gives passengers the benefits of swapping between local and express services, without them loosing time changing trains.
Of course, all of this is a lot easier when you already have the passenger numbers to support it.
NJ transit does do the minimum of express for the farther out places from NYC. Nothing as in-depth as you're explaining. But as you said. The numbers wouldn't support making things too much more complex. That's why my original post mentioned a limit or 7 stops between philly and NYC as an example of a semi-express train. Though a hypothetical express train would probably actually be 5 stops max.
I think straight line distance of NYC -> DC is a little further than Tokyo -> Nagoya, but even the current Nozomi Express Shinkansen would be a huge improvement over Amtrak.
Its absolutely nuts. With all the housing pricing problems we have in the US its crazy to me that we don't have HSR popping up everywhere to ease restrictions on commute.
Turn radius is mostly a cost question. If you want to get from city A to city B the most direct path has zero turns. It's also got stuff you want to avoid to save money.
Hmm, I hadn't thought of the Chuo Shinkansen as "Maglev in a tube" before...
This makes me wonder, if hyperloop research develops reliable vacuum tubing, whether they could encase the overground sections of the Chuo Shinkansen to make it even faster...
The Chuo Maglev makes the Hyperloop One look like a toy project. Watch the video. They have a production-quality train, with tourists and whiny kids riding it, going 500km/h. They've hit 603km/h in tests, but don't run it that hard normally. This is the first section of track between Tokyo and Osaka via Nagoya. Planned opening to Nagoya is 2027. Japan's Alps are in the way. They're tunneling straight through. Longest tunnel segment is 25km and it's being drilled now. 90% of the Tokyo-Nagoya segment will be in tunnel. Stations in Tokyo and Nagoya are under construction. The line will probably run 3-4 trains an hour each way, like the existing Shinkansen.
Hyperloop potentially has a higher speed to 900-1200km/h, but that may not be achieved in practice. The Chuo Shinkansen has a turn radius of 8km, and passengers don't have to be strapped in. Hyperloop would need 4x the radius to go twice as fast with the same ride quality. Laying out a route with a 24km turn radius severely limits where track can go.
Strapping everybody in and pulling 0.5G sustained is not going to go over with customers. Commercial aircraft usually stay within +-0.25G. Maybe 0.5G in mild turbulence, and customers don't like it.
[1] https://www.youtube.com/watch?v=HZ6dYhHIol8