dpeltierFirst off, it misses the second-biggest reason why ECP brakes went nowhere after they were tested in the 2000's. The biggest reason, as everyone agrees, is the lack of a workable path towards full adoption.
Literally in the post "The biggest one is no one has been able to provide leadership that leads down the implementation path. Managing through the change from standard to ECP braking is fraught with problems."
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
BaltACD When I was still working CSX was instructing Engineers that Dynamic Braking was their primary form of braking and the use of air brakes was a secondary braking tool. I can only believe in the past 7 years that the use of air brakes has been incresingly discouraged. ECP or not, if you aren't using air in the first place there is absolutely no advantage to ECP.
When I was still working CSX was instructing Engineers that Dynamic Braking was their primary form of braking and the use of air brakes was a secondary braking tool. I can only believe in the past 7 years that the use of air brakes has been incresingly discouraged. ECP or not, if you aren't using air in the first place there is absolutely no advantage to ECP.
Except in an emergency application where all the brakes would apply at once instead of serially, eliminating the problems caused by severe slack action. Still probably not economically justifiable.
Never too old to have a happy childhood!
oltmannd They are both from the 90s. Only one is entertaining. https://blerfblog.blogspot.com/2023/02/just-stop-it-train-brakes.html?m=0
They are both from the 90s. Only one is entertaining.
https://blerfblog.blogspot.com/2023/02/just-stop-it-train-brakes.html?m=0
This is an interesting essay, but I do think it misstates a few things.
First off, it misses the second-biggest reason why ECP brakes went nowhere after they were tested in the 2000's. The biggest reason, as everyone agrees, is the lack of a workable path towards full adoption. But the second biggest reason is this: economically, there were almost no advantages to the ECP system.
Stopping distances are reduced by half? So what? At best this can make a very marginal difference in track capacity at a few chokepoints. At worst, the faster service breaking is literally never used, because fuel conservation practices already result in a train reducing its speed long before it reaches the minimum stopping distance to the next red signal. (Actually, at worst: engineers start to rely more on air braking and less on dynamics, which increases brake wear. I heard a rumor that was actually an observed phenomenon on ECP test trains.)
Train dynamics are easier to manage? Maybe - the locomotive engineers will have to weigh in on this - but I doubt it? Slack will still be a thing. I don't think most broken knuckles / pulled drawbars / train-handling derailments have anything to do with brake response time.
Runaway prevention? ECP brakes, with their graduated release feature, might prevent some fraction of runaways. These events are so rare that you're talking about a fraction of a very small number; economically, it's not significant.
The only actual payback on the investment came from some FRA regulatory relief. I don't recall the details. I think FRA gave some incentives for ECP trains under a waiver, mostly by eliminating or reducing the requirements of the 1,000 / 1,500 mile inspection. It didn't really move the needle, and might have diminishing returns if you expanded it to non-unit trains.
And all of this leads to my second main complaint about the essay: the reason why the railroads lobbied against the ECP-for-oil-trains regulation was because the regulation was blatantly illegal. Unlike legislation, regulations are required to produce a positive cost / benefit ratio. The regulators, either out of ignorance or for political reasons, totally misunderstood the costs. But more to the point, they didn't understand the so-called benefits and didn't really seem to care. At the end of the day the Transportation Research Board (TRB - the part of the National Academies responsible for providing technical advice to the government on all transportation-related matters) concluded that the regulators simply hadn't demonstrated that ECP brakes would prevent any hazmat releases at all.
So where does this leave us? Well... compare where we are to where PTC was a couple decades ago. Some prototype demonstrations have shown that it is physically possible to implement. The massive cost of PTC was never justified by the safety benefits, and the cost / benefit for ECP is probably tens or hundreds of times worse than it was for PTC.
Where PTC went next was: how can we increase the benefits to include more than just reduced accidents? NAJPTC was probably the best stab at this, and it unfortunately was a miserable stinking failure that kind of shut down that approach for a while. There was also a fair amount of talk pre-Chatsworth discussion about the fact that the only conceivable way to make the economics work was to reduce crew consists. Then Congress adopted the PTC mandate, and the discussion immediately shifted from, "How can PTC really make economic sense?" to "How in the hell can we pull something together that will meet the requirements of the law on the mandated timeline?" Now that it is all in place, the original questions are coming back - how can we use PTC infrastructure to improve operations and reduce costs.
With ECP brakes, I haven't seen much effort to define a new ECP protocol that would add operational benefits. If Congress were to require ECP at this point, it would be a disaster - you only would get one chance to do it right, and the only available technology is not "doing it right".
It would probably be good if FRA and AAR could get together and start working on a next-gen ECP system that has, or is flexible enough to allow for, some actual benefits to the railroad. If nothing else, this would be some insurance against stupid laws in the future.
(My personal moonshot vision: a system that allows autonomous braking for a disconnected car in a yard - program the car with a speed vs distance profile, kick it or roll it down a hump, and let it glide to a smooth joint with no retarder needed. Also, sensors that can measure slack and in-train forces, and a controller at the head and that can apply brakes automatically on individual cars or sets of cars to keep those forces within acceptable range. No idea whether these could be made to work, but maybe a new ECP protocol could at least allow for the possibility.)
Dan
75% of the North American car fleet is private what incentive will you create for; GATX, Mitsui, CAI, VTG et al. to eat those cost?.
I also don't know why braking keeps coming up in a derailment that any form of braking clearly would not have prevented..
Our community is FREE to join. To participate you must either login or register for an account.