this post was submitted on 30 Dec 2024
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cross-posted from: https://lemm.ee/post/51182382

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[–] [email protected] 29 points 5 days ago (3 children)
[–] [email protected] 55 points 5 days ago* (last edited 5 days ago) (1 children)

603 for maglevs, 574.8 for steel rail, set in France in 2007 by a hotted up, modified TGV.

China holds the record for a stock train at 487, set in 2010.

(all per Wikipedia)

It looks like the article might be implying that they will be the fastest trains operating in revenue service when they enter service, but that surely needs to be demonstrated with a production train in revenue service.

[–] [email protected] 6 points 5 days ago (1 children)

...production train in revenue service over the period of usual track maintenance. It's not the rails I'm worried about but the overhead lines, have a look at the TGV record run there's a lot of arcing that can't be good for them. On the pantograph side the contacts are carbon, notoriously brittle, and generally speaking over 300km/h things become dicey just because of heat buildup. Automated retraction systems can prevent the worst, meaning the pantograph getting tangled in the lines at speed, but, well: Production revenue service. Can't have those fail-safes kick in or you'll mess up the timetable.

European high speed trains actually got slower vmax over the years for the simple reason that the rest of the systems is reaching practical limits and it doesn't make sense to have trains that can drive speeds that the track will never reasonably support. If you want to go faster you want to go contactless which means building a whole new, incompatible, network. And the only maglev system with affordable tracks, as in bucks per kilometre (TSB), has a design limit of ~200km/h: It uses bog-standard third-rail like technology for electrification, everything else would be expensive. But for its intended use-case as an S-Bahn 200km/h are plenty and you get nice bonuses such as 10% gradients and inexpensive viaducts (because no point-loads they can be built way lighter).

China, in the end, isn't that large. You can do high-speed sleeper trains, 12-14h or such, from one end of the country to another with existing stock technology, and so btw could the US.

[–] [email protected] 3 points 4 days ago (1 children)

If you want to go faster you want to go contactless which means building a whole new, incompatible, network.

retrofitting and hybrid operation seems possible though: https://en.wikipedia.org/wiki/Nevomo
they already built a small working prototype

[–] [email protected] 2 points 4 days ago (1 children)

I very much doubt they're doing contactless power transfer with nothing but the existing rails and overhead wire. Alsomention of "hypertube" sets of massive alarm bells.

[–] [email protected] 1 points 4 days ago (1 children)

Check out their road map and the videos of their prototypes. It is very much not a tech bro project :). The first goal isnt event maglev but magnetic propulsion.

[–] [email protected] 1 points 4 days ago

The first goal isnt event maglev but magnetic propulsion.

The TSB does the same, on plain steel rails. Levitating on them, using them as what'sitcalled reaction component in linear magnetic propulsion, only the power transfer is direct contact. TSB rails may look a bit fancy but they're two electrified steel beams in concrete casing. Your Poles may be working on an improvement to linear motors but it's not a new concept. Thinking of it they should look into breaking applications: Mechanical breaking causes massive wear so fast trains are using induction brakes but those don't work to bring the train to a complete standstill, but if the brake is a linear motor it could do that. Selling magnetic brake tech to Siemens or Alstom would probably set the lot of them up for life.

The company developed TSB because they were part of the Transrapid consortium, responsible for the track, and judged that ultimately track cost was why the whole thing failed to materialise, so they sat down and said "what's the cheapest track we can build" and then designed the rest of the tech around that. Cost differs depending on lots of details but overall they're actually cheaper than standard rail, doubly so if you take lower maintenance costs into account.

[–] [email protected] 25 points 5 days ago* (last edited 5 days ago) (1 children)

Yes,

If it has an operating speed of 450km/h this would be impressive.

But just reaching this speed is far from a world record, the French TGV record from 1990 is 513km/h, it reached 574.8km/h in 2007 which is the current world record.

[–] Valmond 14 points 5 days ago (2 children)

And they thunder around at 300-360km/h all day every day.

[–] [email protected] 4 points 5 days ago (1 children)

Wind resistance is a problem at speed which is why production trains rarely go faster. Airplanes at altitude see much less win resistance. (hyperloop would also be good but will never be reasonable to build even if the engineering challenges are overcome)

[–] [email protected] 6 points 5 days ago (1 children)

Japanese bullet trains had to get a redesign due to something akin to sonic booms when leaving tunnels that annoyed the hell out of residents several times an hour.

[–] [email protected] 3 points 5 days ago

Noise is another issue of course but energy is what will kill faster trains for forever

[–] [email protected] 3 points 5 days ago

I love driving, so much freedom🤡

[–] [email protected] 23 points 5 days ago* (last edited 5 days ago) (1 children)

Not to be left behind, the west invests in an even faster next-gen train codenamed "snowpiercer."

[–] [email protected] 29 points 5 days ago

Taller, more aggressively-styled SUVs with poorer visibility is the best we can do

[–] [email protected] 22 points 5 days ago (3 children)

I swear to god, if the west can't get their shit together real fast I'm going to have to start learning some mandarin

[–] Valmond 18 points 5 days ago (2 children)
[–] [email protected] 14 points 5 days ago (1 children)

Learning mandarin seems the better option then...

[–] Valmond 9 points 5 days ago

To each their own I guess 🤷🏼‍♀️

[–] twen 2 points 3 days ago

Or go to Spain or Germany, or Italy. They all have high speed trains (300-320 km/h commercial). , Spain has the largest high-speed network in Europe.

[–] [email protected] 3 points 5 days ago

It's a good bet regardless

[–] UnderpantsWeevil -2 points 5 days ago (1 children)

Lots of good cinema and books in Mandarin. And you don't need to dig through all the AI Slop filling up the English language outlets.

[–] [email protected] 13 points 5 days ago (1 children)

AI writes in all languages. Also mandarin.

[–] j4k3 0 points 5 days ago

It might add a little flavor, maybe a little color. Better set those softmax settings to deterministic.

[–] [email protected] 17 points 5 days ago (1 children)

The US is set to unveil their high speed competitor soon with a train called the "American Superior." It is stated to have a top speed of 80km/h and will launch on a single 10km track by the year 2083.

[–] [email protected] 5 points 4 days ago

At a cost of 185 billion dollars. CEO is paid 109 million annually, and there's a board of 126 directors

[–] [email protected] 4 points 5 days ago

"Always bet on bullshit." -Wesley Snipes, probably

[–] [email protected] 2 points 5 days ago (1 children)

As someone who frequently uses Japan's bullet trains, that max speed is cool, but also of limited value since trains tend to stop in places. There are some areas, moreso in china that Japan, where that might make sense, but even if your train doesn't stop at all stations, you're still behind the ones that do until a track split to allow passing.

[–] pycorax 4 points 4 days ago (1 children)

Isn't scheduling able to mitigate issues like that? It helps a lot that Shinkansens are pretty much always on time. Can't wait for the Chuo to open eventually though.

[–] [email protected] 2 points 4 days ago

You've already got various services running on the same lines basically as close together as they can, so there's only so much wiggle room to accomdate something faster than all of them longer stops on existing services could do something, but that has other knock-on effects. Building a new rail and retrofitting every station would work, but it's also a nightmare to both get the land and do all that development.