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Comment by onetimeusename | Hacker News Reader

I am not convinced electronically controlled pneumatic brakes would have made a big difference here[1] during an emergency stop. Some difference, sure. But keep in mind that 50 cars out of 141(IIRC) derailed. This is not a defense of any specific policy. I just think people are treating the EPC brakes as if they would have completely prevented the accident.

[1]: https://www.ntsb.gov/news/events/Documents/2017_casselton_BM...

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ECP brakes are generally per train and freight car or car block. Any single car or block installed with them likely wouldn't haven't made a difference, but more probably, in an environment with lax adherence to (or even avoidance of) safety technology guidelines, there is no guarantee that an ECP braking system would have been operably configured and maintained.

In the condition this train was at, whether they were equipped or not is irrelevant, because they'd more than likely just have been expensive decorations.

Even assuming they performed optimally, the reduction in stopping distance would not have been anywhere near 100%. It depends on train length, weight, and speed, and some other train car standards but a mean estimate would be a 13 to 39% reduction in the stopping distance. How many less cars does this translate to as far as a derailment? This study [1] suggest 20% less. Contrast that with an official saying that ECP brakes would have "avoided that monster pile up"[2]. If 50 cars derailed then maybe we could see ten fewer cars derailing in a similar accident. Is that worth it? I don't know. But I don't believe it would have completely prevented it.

[1]: https://www.gao.gov/assets/690/680555.pdf

[2]: https://www.usatoday.com/story/news/2023/02/14/norfolk-south...

In my limited knowledge weren't ecp brakes part of the ability is to prevent large trains from derailing, and being able to stop independently?

The older braking system, that was currently installed on those trains, has more points of failure.

they would likely reduce the number of derailed cars

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