3 ms·
More predictable maybe, but also way more intensive (only 30-60 seconds between trains, vs rural freight where many lines only see one or two trains per DAY, or
by TylerE 1y ago
More predictable maybe, but also way more intensive (only 30-60 seconds between trains, vs rural freight where many lines only see one or two trains per DAY, or even per week.
- frosted-flakes 1y agoAre there are metro systems that run trains 30 seconds apart? I think the fastest is around 90 seconds. Rarely used freight lines (aka branch lines) would never be automated, that wouldn't make sense. And some mainlines (I live near one) see as many as 4 100-car freight trains per hour. Those will never be less than one-man operation either, not least because at-grade crossings are everywhere.
- o11c 1y agoIf there's one thing we should know from the computer world, it is that doing something frequently makes it easier to automate.
- TylerE 1y agoThe problem is that they run close enough together that any failures rapidly cascade until suddenly your whole network is a half hour late as it grinds to a halt...
- IAmBroom 1y agoAny such failures are potentially massively fatal, and grinding to a halt is exactly what we want the trains to do. All that means is that you design the system very robustly. And, of course, trains fail-to-safe. Cut a brake line? Train can't release its brakes. Signal out? Conductor can only move in GoA0 (manual), at reduced speeds, until the next signal is reached (and readable). Etc.