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by tialaramex 293 days ago
There's also some "infant mortality" stuff, the EMUs (Electric Multiple Units, which I suppose is roughly what this is?) in my country have not good failure rates in their first weeks and months but they get much better (typically best in class due to fewer moving parts than say a diesel) in mid-life.

Brake performance is a thing you can simulate and measure on a test track, which presumably happened at least months ago. However loss of adhesion, the reason braking stops working on contaminated railheads is also impacted by moisture, a bunch of dry leaves won't make anywhere close to the same problem as the same leaf material after a nice gentle drizzle, not really rain per se, not enough to actually wash the rails clean, but ensuring the leaves turn into a thin mush that makes braking next to impossible.

RAIB report 12/2023 about an incident near me talks about that, the driver maybe makes some dubious decisions, but ultimately he brakes, and it does nothing, so he brakes harder, still nothing, maximum braking, still nothing, select emergency braking (same effect but hey, it's there to be used right), still nothing - oh shit, we've passed the danger signal and I see another train, time to leave. He actually spent ages in hospital because he tripped trying to flee and was trapped in the wreckage, but on the other hand if he'd just sat there frozen he might well be dead 'cos his train did indeed smash into the other one so the side where the driver is sat smashed into another train at like 50+mph.