alt Hacker NewsShort answer: Japan treats high-speed rail as a tightly controlled system, not just fast trains on tracks.
One major difference is infrastructure. Shinkansen lines are completely separate from conventional rail: no level crossings, no shared tracks, no freight, and no interaction with slower services. There are no cars, pedestrians, or animals anywhere near the line. In much of Europe, including Spain, high-speed lines are very good, but they still tend to interact more with legacy rail networks and inherit more constraints.
Another key factor is how strictly operations are controlled. Speed limits are enforced automatically rather than relying on driver compliance alone. If a train exceeds its permitted speed for any reason, the system intervenes immediately. The design assumption is that human error will happen, so the system is built to prevent a mistake from turning into an accident.
Maintenance is also handled with extreme conservatism. Track geometry, overhead lines, and rolling stock are continuously monitored, with very tight tolerances. Components are replaced earlier than strictly necessary because preventing failures is considered far cheaper than dealing with the consequences of one.
Japan has also invested heavily in detecting external hazards. Earthquake early-warning systems automatically cut power and apply brakes before shaking reaches the tracks, and the same mindset applies to weather, landslides, and other environmental risks.
Finally, there’s a strong institutional safety culture behind all of this. Procedures, training, and reporting of near-misses are taken very seriously, and lessons are applied incrementally over decades. The objective isn’t just to meet safety standards but to systematically remove edge cases.
It’s not a single piece of technology that explains the record. It’s the combination of dedicated infrastructure, automation, conservative engineering, obsessive maintenance, and a culture with very little tolerance for shortcuts.
Replies
Japanese high speed tracks get checked (and repaired/replaced, if required) every night. During the midnight-to-6am window.
That's why something like a fractured high speed rail track would never go undetected in Japan.
https://www.plassertheurer.com/en/today/stories/japanese-pre...
https://global.jr-central.co.jp/en/company/data-book/_pdf/20...
https://www.ejrcf.or.jp/jrtr/jrtr61/16_21.html
https://international-railway-safety-council.com/wp-content/...
Spanish high speed lines are mostly separate from the legacy network as they have different gauges, there are a few parts of the railway with dual gauge tracks but it is that. The Santiago accident was on the conventional rail.
Just a small clarification, Spain has two distinct track stems for normal trains (Iberian gauge) and high speed rail (international gauge). High speed rail is completely separate from the iberian gauge network which is primarly used for city and regional trains. Only a few cargo trains use the high speed network.
Regarding the second point, 2013 accident was caused by higher than allowed speed and drivers had been complaining about the line not having the security system that automatically enforces speed limits. In this year's accident, the line has a much stricter securty system.
The main issue with spanish rails, high speed and specially traditional rail is the lack of maintenance.
Minor correction: there are two Shinkansen lines in Japan that run trains partly on shared legacy track, namely the Akita and Yamagata "mini-Shinkansens". However, these sections operate at normal speed, not high speed.
>If a train exceeds its permitted speed for any reason, the system intervenes immediately
That might be because Japan did have a huge railway accident in 2005 due to excessive speed.
https://en.wikipedia.org/wiki/Amagasaki_derailment
> Of the roughly 700 passengers, 106 passengers and the driver were killed, and 562 others were injured
The Santiago de Compostela derailment (first link on the parent comment) happened in 2013 for the same reason.
All that said, I would not be surprised if the culprit for this particular case is lack of maintenance. However I would wait until the official investigation is over before drawing conclusions.
> If a train exceeds its permitted speed for any reason, the system intervenes immediately.
Does the system automatically slow down the train, or does it notify the engineer? I would imagine that there are some scenarios where going over the speed limit is the correct choice.
Please don’t post slop when people ask thoughtful questions.
Edit: someone down this thread pointed out the answer is likely written by AI. If you copy the whole post from GP into ChatGPT it will give you an answer very similar to the post I am replying to.
> Shinkansen lines are completely separate from conventional rail: no level crossings, no shared tracks, no freight, and no interaction with slower services.
Not true.
https://www.youtube.com/watch?v=TYol11bVoNw
https://ameblo.jp/nakamurapon943056/entry-12488005292.html
> but they still tend to interact more with legacy rail networks and inherit more constraints.
Spanish high speed trains mostly run on their own tracks because of gauge differences. France and Germany are the ones who actually runs high speed trains on old tracks, a lot.
It is surprising how many upvotes you can get on the internet just by glazing the Japanese.