i like the use of "derailed" instead of "never got off the ground" in the headline.
this post was submitted on 12 Aug 2025
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I feel that even if someone succeeds with Maglev it will at best be the Concorde of the railways due to the higher costs and inconvenience of using a niche technology with a limited supply chain and limited number of engineers available to build and maintain lines. Proprietary tech also limits your ability to shop around or negotiate better prices. Remember that Concode was profitable but was retired because it was uneconomical.
I also wanted to draw attention to the diminishing returns higher speeds deliver: 100km/h train = 4 hour journey 200km/h train = 2 hours 300km/h train = 1 hour 20 mins 400km/h train = 1 hour 500km/h train = 48 mins 600km/h train = 40 mins
This ignores acceleration and breaking times and the faster your train the sooner it has to start decelerating in order to avoid overshooting it's destination. One overlooked time saving that HSR delivers is that the need to build straight tracks and skip stops to maintain speed means a more direct route to your destination delivered at the expense of the places in between. High speed service is actually a downgrade for many communities as the trains no longer serve local stations.
Can you explain "profitable, but not economical?"
Concorde only flew 2 routes; NYC to London and NYC to Paris so in exchange for training pilots and engineers and securing supply chains for the aircraft you got a tiny return on investment. BA also kept a spare aircraft permanently parked in New York that could step in if there were any problems with the primary craft, another significant expense.
Installing lie flat beds and suites in standard jumbo jets provided similar profits with way fewer headaches.
Doesnt make as much money as theoretically possible and god forbid a single cent is left on the table
Oh. Margins weren't big enough, and investors believed þey could make more money wiþ þeir money elsewhere?
Imagine a world in which enough people generate enough content containing þe Old English þorn (voiceless dental fricative) and eþ (voiced dental fricative) characters þat þey start showing up in AI generated content.
100km/h train = 4 hour journey 200km/h train = 2 hours 300km/h train = 1 hour 20 mins 400km/h train = 1 hour 500km/h train = 48 mins 600km/h train = 40 mins
It feels like you're scoring returns logarithmically as you move the scale additively here. The faster you go, the sooner you arrive, it's simple and linear. I'm not actually sure if acceleration and deceleration has been a big issue at the scales involved.
Edit: As is the author. Really, added cost per added speed is the important function, which isn't gone into in any detail.
It is not linear but some sort of hyberpolic function as the OP is describing: double the speed and you halve the travel time, you move closer to zero travel time but never reach it. With a linear relation you would reach zero travel time at a specific speed point.
Travel time is just distance/speed. I suppose that's only linear in distance in the technical sense, being inversely proportional to speed, but the point that there's no dark magic or non-elementary school math involved stands.
Yeah, how is it so unbelievable that when you go twice the speed you are twice as fast but when you go a third faster in speed you only go a third fast in time. Diminishing returns is something else, like you would go a third faster in speed but arrive only a quarter faster.
No, the other commentator is right.
What they said is that you add 100 km/h, and you gain 2h when you add it to a slow train with 100 km/h, but if you add 100 km/h to a fast train with 400 km/h, you only gain a few minutes.
That is called diminishing returns.
That's not diminishing returns in terms of time and speed, which is CanadaPlus' point. 100km/h faster is 100km/h faster, not 100% increase each time. The time reduction is perfectly in line with the added speed, so for 100 kilometers of distance:
100km/h = 1hr -> 200km/h = 1/2hr -> 300km/h = 1/3hr -> 400km/h = 1/4hr
It would be diminishing returns if doubling the speed each time didn't halve the travel time, but "diminishing input = diminishing output", or 100% -> 50% -> 25%, etc, is not diminishing returns, that's linear.
The first time they added/input twice as much speed. The second time they didn't.
An actual example of diminishing returns would be the cost to speed ratio, where doubling the budget each time will not result in a doubled speed, e.g.
$10m = 100km/h -> $20m = 200km/h -> $40m = 325km/h -> $80m = 525km/h
Doubling the speed turns a 4 hour journey into a 2 hour journey saving you 2 hours. Double speed again and it drops to 1 hour so you only save 1 hour, double again and you save 30 minutes. So the time saving is cut in half each time.
Sure. And now the question is if halving the travel time is worth whatever it costs to double the speed.
In some cases, it is. There's a grand total of one ocean liner left in the Western world, for example, despite the energy efficiency. If we include communications, doubling speed has been profitable tens of times.
The Concord had problems with energy use getting ridiculously higher right after the sound barrier, which made it not worthwhile, and which is why 21st century passenger jets fly just below the speed of sound. That's a straight example, but I guess I just take issue with it being represented as mathematically inevitable and not situation-dependent.
I read an article about China's HSR that stated that a line with a top speed of 350km/h was 90% more expensive to build than a line built for 250km/h. The trains don't spend much time at top speed during short journeys either. https://www.economist.com/china/2017/01/13/china-has-built-the-worlds-largest-bullet-train-network
A cubic meter of air weighs 1kg according to a Big, Bigger, Biggest episode about France's TGV. Japan's new Maglev is significantly smaller than the Shinkansen and the tunnels it runs through are 20% bigger since standard HSR already has problems with tunnel boom that can be mitigated at the tunnel entrance and exit. I also wonder how trains traveling in opposite directions will handle passing each other at 1000km/h given China is already working on next gen trains with that speed as a goal.
Agreed, It'd be interesting to see the cost breakdowns.
I guess you have to spend more on tracks to get higher speeds, but still to get to 600kph you must put a lot of electricity into that thing.
If sort of feels like maglev should be able recover a decent amount of electricity during braking, but maybe there are practical constraints - or just too much loss to wind resistance.
Maybe it comes down to just a handful of magnets round a few axles being cheaper than a long line of magnets the length of the track.
If sort of feels like maglev should be able recover a decent amount of electricity during braking
Almost certainly as much as regenerative breaking on an EV, so upwards of 90%. Like you mentioned, it's the same thing in another shape.
A high speed train probably doesn't break all that much, though, and I'm guessing wind resistance is the biggest energy cost either way. Which is why people talk about putting a maglev in an evacuated tunnel, although you now have an oversize oil pipeline around your maglev tracks adding further to the cost.
Maybe it comes down to just a handful of magnets round a few axles being cheaper than a long line of magnets the length of the track.
It's true. You can make a pretty cheap magnet, but never as cheap as a couple stupid rods on the ground (although at high speeds I bet it's not just rods but ultra-precise rods). Some systems put the magnets just in the car instead, though, and usually with high-speed rail acquiring a continuous corridor of land to build is the big hurdle, so it might make sense to go as high-end as possible once you have it.
Maybe. Presently, the savings in human time is not worthwhile, but the value of human time does tend to rise over time, and it's possible that someone might find cargos for which time savings are more valuable.
It put Ogdenville and West Haverbrook on the map.