RandallW wrote: ↑Wed Feb 22, 2023 5:36 am If ECP braking were installed, wouldn't it have caused all cars to brake at as close to the same time as possible given the speed of light instead of leading cars braking before trailing cars?
taracer wrote: ↑Wed Feb 22, 2023 8:20 am Yes, the "signal" to apply, or release the brakes, would be practically instantaneous with ECP brakes. On the giant PSR trains run today, I can count with my hands how long the signal takes to travel, the air being that signal. It's even slower in cold weather, like nowWould it? How long does it now take to walk and correctly inspect a 1.5 mile long consist? Would that still be necessary with a competent ECP+ system with diagnostics on each piece of rolling stock? Automobiles have had brake-wear sensors for years; why not rolling stock? [What exactly does FRA require be inspected during that walk?] Such a system could test-cycle the brakes at initial startup.
That instant setup on all cars would certainly reduce the forces evolved, but that would add complexity and more inspections to make sure the system is working on the cars themselves since they take a lot of abuse.
It would require more people and more downtime and once again, PSR can't have any of that.
Yes, it would more complex to design, but to run? (How much do you need to know about the BIOS diagnosis on your laptop? It runs, your box boots, or fails with an error message.) I can easily see the FRA allowing one car with marginal/failed brakes iffin it was in a 50+ car consist of a given weight, etc.
And once you have a per-car microcontroller, hot box sensors are almost trivial. So would be car weight sensing, and antilock braking; that would reduce wheel wear $$$. Further, on non-emergency brake applications, the system could start blended braking at the rear and move forward car by car, keeping the train taunt, if that's desired.
I see the railroad industry as in a place rather like the Bell System was decades ago; Ma stubbornly stuck to "We've always done it that way; why change now?" until it collapsed under its own weight. Yes, there are significant differences but also parallels.