Re: Pressure suits?
So?
It's 1200km from Beijing to Shanghai and takes more than 5 hours on the current 300km/h trains.
That's a small run compared to many of the distances in China. It's a _big_ country - only slightly smaller in square miles than the USA lower 48.
I can easily see the 300km/h(*) lines being used for shorthaul and tubes for longer runs. Even on short runs, it doesn't matter if the pods don't hit 1900km/h, they'll still be much faster than the trains for distances of 300km.
(*) Many of them have just had their speeds returned to 350km/h
With upwards of 200 million people moving en masse at chinese new year, many will happily pay a premium to not have to sit on a train or aircraft for 6-8 hours and the rest will be happier the trains are less crowded.
The interesting part of all this is not the tubes - they're relatively easy - but how to safely handle stub switching for routing and how to handle multiple pods in flight. Should they dynamically link up into a train or should they run with separation, etc?
If china's contemplating this and decides to act, then it will happen. This is a country which went from no fast rail to more high speed rail than the rest of the world combined in less than 20 years - and running at higher speeds too(**). Their specialist rail building equipment is mind boggling (look up the bridge building videos on youtube) and can teach more than a few lessons to infrastructure builders in the rest of the world.
The knock-on economic benefits of this kind of infrastructure are only just starting to make themselves obvious to outsiders, particularly when china's freight rail network has had a similar overhaul with far less fanfare.
(**) Yes, two crashes, yes lots of corruption discovered - but they've nailed that down and fixed the technology. European high speed rail has had just as deadly crashes.