Some people are skeptical this technology can ever work, but it appears CASIC’s Phase 1 testing in a 2km tunnel has given them the confidence to proceed to Phase 2 testing in a 60km long tunnel.
Chinese railway engineering leads the world so I have a hunch that if any nation can pull this off, then it’s China. However, lots of questions remain. A back-of-the-envelope calculation says that to achieve those speeds in the 2km test tunnel deceleration would have been about 3G. That’s the same as a rocket at lift-off and not many people’s idea of comfort.
The concept and technology isn’t the issue. It’s just not economically or technically feasible at scale.
Its literally just not worth it, all while being stunningly dangerous. When a zero pressure vacuum ruptures, it violently contracts, generally crushing itself.
This will require a zero pressure vessel as wide as a train, that is hundreds or thousands of miles long to be viable. One hole in the thousand mile line will shut the whole system down while it’s repaired and then depressurized. This strands any other trains in the tunnel until this is done, so your “superspeed” tunnel is really super slow. Even if they have some kind of "safety valvue at set intervals that means the whole line doesnt go down on pressure gain, you still cant use the rest of the line.
So for this to work, you need multiple redundant tunnels, all of which can be taken down by one person with a gun at any point along a long, long track.
So you can spend just endless billions, literally hundreds of billions, making these redundant train tunnels that still aren’t redundant, or you can spin up 10x-100x as much HSR that goes 300km and actually interlink the country with truly redundant and fast transportation.
The technology problems can be solved. However I don’t see how anyone can afiord to build it.
I got an acceleration of 1.5G for the test, did you forget a factor of 2 or something? Still certainly not an enjoyable experience for passengers, but I assume it would accelerate over a much longer distance if a full track was built.
Did you also factor in that the train needs to come to a full stop in that 2km as well?
I think I’d probably be fine with 1.5Gs as long as the jerk and snap were low.
At 1000 km/hr, it’d run out of track in less than four minutes, hope it can stop in time … Anyway not convinced there’s much point in this. China should be building more suburban rail networks to fill the gaps, instead of pouring so much concrete into crazy-wide highways and toll-roads (look on satellite image, you’ll see).
Except the concept is already “proven” in that regard. What the issues are with it, are the same as with everything techy that needs to make it in the world - scaling it up.
It’s impossible to hold a vacuum in a tube that’s hundreds of kilometers long. It is impossible to build a vacuum tube that doesn’t suffer because of thermal expansion. It is impossible to build that long of a tube and it not have a single dent in it across the entire way. Even if you somehow ignore physics, people don’t need a train like this. There is flights. Travelling at reasonable speed has been proven for hundreds of years.
To explain it in a tldr way, I can grab a straw, put a wet tissue inside it, blow on it and in relative speeds it would go incredibly fast. Yet nobody would go for trying that with a train, since scaling it is impossible.
After everything I’ve seen with tofu-dreg construction like that bridge collapsing this last week, I think I’ll pass on riding a nearly supersonic Chinese train.
Norway has enough money to build one from Kirkenes to Kristiansand. But they never will.
