I see what you're saying but innovation in high-speed mass transport is going to take a breakthrough in tech: could be sabre, could be hyperloop, could be superconducting maglev. Despite what your spidey-sense is telling you, maybe this is one of the breakthroughs we need. Having said that I think we should be aiming for low environmental footprint with all our tech from now on given what we know about the damage we're doing. I'd like to see these breakthrough techs compared in terms of environmental costs.
My ideal combo would be superconducting maglev high-speed trains coupled with nuclear power to deliver the electricity.
For mass transit high speed only makes sense for longer distances. Most mass transit is relatively short haul where the acceleration/deceleration times (that still provides a comfortable ride) prevent you from saving any time.
Over the speed of sound is great if you want to fly half way around the world. But from Paris to London it doesn't really save you much. Unless it becomes cheaper than regular air travel.
> For mass transit high speed only makes sense for longer distances. Most mass transit is relatively short haul where the acceleration/deceleration times (that still provides a comfortable ride) prevent you from saving any time.
Probably I just should have said superconducting maglev trains. I guess you're right that they only need to be properly high speed over longer distances. Superconducting maglev would be a win for acceleration/deceleration as well so would benefit short haul.
Realistically speaking, inexpensive superconductors would be a total game changer for many fields, not just mass transport.
> Over the speed of sound is great if you want to fly half way around the world. But from Paris to London it doesn't really save you much. Unless it becomes cheaper than regular air travel.
I kind of feel that in general it'd be better to replace planes with trains, than to replace planes with better or faster planes. Better security-wise. Better for the environment in the long run I believe. I'm totally open to correction though.
> Superconducting maglev would be a win for acceleration/deceleration as well
This limitation isn't at all technological. You just can't accelerate or decelerate much faster than today's high speed trains without causing discomfort to your passengers. And the radius of any turn increases with speed. Otherwise first you just produce noticeable discomfort while turning, and beyond that you risk derailment (no matter the rail type). So you're basically stuck with having really long and very straight stretches of rail where you have to gently accelerate and decelerate. On any short trip this would kill any economy of high top speed.
> I kind of feel that in general it'd be better to replace planes with trains
The advantage of flight is that you are free to take a more or less straight path between the 2 points without caring about what's below. But with any kind of land transportation you need to deal with rivers, mountains, lakes and seas (not to mention oceans), cities and other man made structures, etc. Without a breakthrough in engineering I don't see how you can go from London to Los Angeles in a reasonable time.
> This limitation isn't at all technological. You just can't accelerate or decelerate much faster than today's high speed trains without causing discomfort to your passengers.
Will electric cars change people's comfort with longitudinal acceleration? Imagine people's family SUV does 0-60 at 5 m/s^2 (Tesla Model Y), and sedan around 10 m/s^2 (Model 3 and S). Then subway's ~1 m/s^2, shinkansen's 1.2, or TGV's 0.5, may seem very last century. A generic Honda Civic looks about 3.
We can do it but it won't be comfortable. It would be "roller coaster fun" (similar acceleration). You have 500 people on a train (half of them facing backwards) and want to give them a comfortable ride. Including keeping the coffee in their cups or their stomachs :). Again, it's not a technological challenge, it's a biological one. The human body doesn't evolve faster because we have capable cars.
At 5m/s^2 we're talking ~0.5G, more than what you feel in a plane taking off (normally ~0.4G) and one order of magnitude higher than most high-speed trains accelerating (~0.03-0.05G). This is not a normal or comfortable regime. And at 0.2G lateral acceleration (in curves) you have a good chance of seeing your lunch again. This means at 600Km/h you need 15-20Km turn radius. Add to that the air turbulence at close to and over 500Km/h at sea level which causes a rumble that's nausea inducing for most people (riding in low pressure tubes may help here).
People don't expect to be able to get work done in a passenger car. Train passengers (especially the lucrative business sector) expect their laptops to stay on the table.
Another factor - half of all train passengers are facing backwards.
My ideal combo would be superconducting maglev high-speed trains coupled with nuclear power to deliver the electricity.