I would opine that an automotive analogy would be someone with a CDL-B (ie, straight frame) driving a truck which requires a CDL-A (bends in the middle).
The CDL-B driver is certainly certified to drive a truck, just not a semi.
In the railroad world, such a distinction does not exist. If you’re qualified as a road engineer, you’re qualified for anything from one car to 200+.
[quote user=“Overmod”]
You’ll never get much of anywhere until you understand the actual mechanics and consequences of bearing failure in three-piece freight trucks, and what was observed during the East Palestine accident.
There are two tapered roller bearings on the axle end: one ‘inner’ and one ‘outer’. These are often mounted as a ‘package’ and grease-lubricated (AAR spec) for supposed long life without ‘breaking’ for maintenance.
The inner bearing is, relatively, the more important of the two, as its failure will be more likely to progress to axle breakage, or seizure causing wheel failure, than the outer.
But the outer is the only one whose failure would be readily detected by the usual kinds of ‘hot bearing detector’, which are IR scanning to distinguish the relatively ‘point’ source of a hot end cap from the larger signature of an overheated wheel (for example due to a sticking manual brake).
Any catastrophic failure of the inner bearing (you will find reports online describing what causes these, and how rapidly they can develop) easily proceeds to axle-damaging temperature before enough heat passes out to the endcap to show the temperature rise that triggers current response.
The source of all the fire in the camera records leading up to the East Palestine derailment was NOT A HOT BEARING. You can even see on the doorbell-camera footage that the truck itself has skewed and is dragging, producing sparks and flame between the rails.
The crew, not being fools or trained poorly, thought they understood the best way to stop a long train in the presence of an overheating bearing – not realizing what was actually happening back there. The sensible thing is precisely what they did: put the train in dynamic to slow it without additional heat, drag. or risk of seizure from brakeshoe application. Now, you of all people should be sensitive to the issue of what
Almost all hot bearing detector locations also include a dragging equipment detector. If the East Palestine detector had one it should have alarmed for a dragging truck.
If the engineer knew exactly what the situation in the train was he probably could have reduced the severity of, or maybe even prevented the pileup by making an emergency application of the brakes from the rear end using the end of train device.
Thank you for that information. I understand your point about stopping the train with slack stretched by initiating an emergency application from the rear end. In so doing, even if the truck had broken up, the stretched train might have ridden it out without buckling. It could have prevented the entire pileup and spills.
But apparently, the engineer relied exclusively on dynamic braking. In any case, rather than the alternative of initiating an emergency air brake application starting at the rear of the train; is it possible to initiate dynamic braking only on the rear DPU, if there is one?
If that is not possible, and DPU provides only equal dynamic braking on all units; how much dynamic braking force is possible or allowed? How is that controlled? Is it just a matter of the engineer’s discretion; or is there some type of automatic control that factors train makeup, tonnage, speed, and DPU location, in order to prevent excess buff force? Or is the safe level of dynamic braking just controlled by rules?
[quote user=“Euclid”]
mvlandsw
Almost all hot bearing detector locations also include a dragging equipment detector. If the East Palestine detector had one it should have alarmed for a dragging truck.
If the engineer knew exactly what the situation in the train was he probably could have reduced the severity of, or maybe even prevented the pileup by making an emergency application of the brakes from the rear end using the end of train device.
Thank you for that information. I understand your point about stopping the train with slack stretched by initiating an emergency application from the rear end. In so doing, even if the truck had broken up, the stretched train might have ridden it out without buckling. It could have prevented the entire pileup and spills.
But apparently, the engineer relied exclusively on dynamic braking. In any case, rather than the alternative of initiating an emergency air brake application starting at the rear of the train; is it possible to initiate dynamic braking only on the rear DPU, if there is one?
If that is not possible, and DPU provides only equal dynamic braking on all units; how much dynamic braking force is possible or allowed? How is that controlled? Is it just a matter of the engineer’s discretion; or is there some type of automatic control that factors train makeup, tonnage, speed, and DPU location, in order to prevent
I have said no such thing, and from someone who is repeatedly touchy about allegedly being misquoted, I find it verging on insulting that you claim so.
In my opinion, the original cause of the accident was likely an inside roller bearing, failing in one of the catastrophic ways that result in rapid degradation. This was not ‘picked up’ for the reasons others, and I, have already discussed. In all likelihood this resulted in the axle end overheating and shearing off, which would drop the end of the sideframe down and ‘cock’ the wheelset laterally with respect to both rails. The amount of fire appears consistent with wheels against rails in this type of situation, and it is not surprising to me that it might persist past a couple of sets of outside bearing detectors with only a nominal temperature rise from ‘outer bearing’ overheating being reported. I also suspect, but haven’t rigorously considered as I haven’t seen the detail data, that the rate of rise in detected temperature was out of all proportion to the “heat” evidenced on the cameras.
Yes, the proximate cause of the derailment was likely putting the locomotives “too quickly” into heavy dynamic braking, resulting in progressive run-in that would normally just cause audible slack action. The shock to the front of the car with the damaged truck would have caused the prompt lateral deflection that would resuit in accordioning.
On this topic:
Always entertained by what I see on Facebook and other social media. My favorite was a youtube clip sent to my facebook account of a Locomotive Engineer at a small museum (my guess), have problems believing it was part of the frieght carrying rail network. Backing up a locomotive to couple onto a snowplow, the camera inadvertently caught a pinneapple bong set up next to the control stand on the dash. It was pointed out by one of the posters in the comments section. Now granted it could have been there for decorative purposes but look at the public image that conveys and the suspicions it would raise by a visiting inspector.
Those stupid over-edited garbage shorts are made for reactions (ooh… so edgy!). I don’t think an engine ever actually moves in any of them.
Has ANY official report identified the Initial Point of Derailment.
Until that is made public, everything else is hot air.
Euclid
mvlandsw
Almost all hot bearing detector locations also include a dragging equipment detector. If the East Palestine detector had one it should have alarmed for a dragging truck.
If the engineer knew exactly what the situation in the train was he probably could have reduced the severity of, or maybe even prevented the pileup by making an emergency application of the brakes from the rear end using the end of train device.
Thank you for that information. I understand your point about stopping the train with slack stretched by initiating an emergency application from the rear end. In so doing, even if the truck had broken up, the stretched train might have ridden it out without buckling. It could have prevented the entire pileup and spills.
But apparently, the engineer relied exclusively on dynamic braking. In any case, rather than the alternative of initiating an emergency air brake application starting at the rear of the train; is it possible to initiate dynamic braking only on the rear DPU, if th
[quote user=“mvlandsw”]
Euclid
mvlandsw
Almost all hot bearing detector locations also include a dragging equipment detector. If the East Palestine detector had one it should have alarmed for a dragging truck.
If the engineer knew exactly what the situation in the train was he probably could have reduced the severity of, or maybe even prevented the pileup by making an emergency application of the brakes from the rear end using the end of train device.
Thank you for that information. I understand your point about stopping the train with slack stretched by initiating an emergency application from the rear end. In so doing, even if the truck had broken up, the stretched train might have ridden it out without buckling. It could have prevented the entire pileup and spills.
But apparently, the engineer relied exclusively on dynamic braking. In any case, rather than the alternative of initiating an emergency air brake application starting at the rear of the train; is it possible to initiate d
Jeff,
Can the lead units be put into power after the DPU is put into dynamic braking? That could be useful when the headend is starting uphill while the rearend is still on a downgrade.
Mark
In the case of the East Palestine wreck, I understand that that the train was applying dynamic braking to slow down for another train they were following. At that point, the crew knew nothing about the status of the overheated bearing.
Suddenly, they were warned and commanded by a detector, apparently on the south edge of East Palestine, to stop immediately. So the engineer increased dynamic braking and the train immediately buckled and piled up. That buckling caused an Emergency air brake application, which added to the deceleration already occurring due to dynamic braking and the resistance of the developing pileup.
QUESTION: When the crew received that warning from the detector; how long would it have taken them to reconfigure dynamic braking controls so that only the rear DPU would respond to engineer- initiated, control calls for dynamic braking?
It seems to me that the Company would have had a formal protocol in place, calling for that action in a situation where the train is extremely likely to experience a mid-train buckling.
Converting to rear-DPU-only dynamic braking seems like the perfect solution that might have
[quote user=“Euclid”]
In the case of the East Palestine wreck, I understand that that the train was applying dynamic braking to slow down for another train they were following. At that point, the crew knew nothing about the status of the overheated bearing.
Suddenly, they were warned and commanded by a detector, apparently on the south edge of East Palestine, to stop immediately. So the engineer increased dynamic braking and the train immediately buckled and piled up. That buckling caused an Emergency air brake application, which added to the deceleration already occurring due to dynamic braking and the resistance of the developing pileup.
QUESTION: When the crew received that warning from the detector; how long would it have taken them to reconfigure dynamic braking controls so that only the rear DPU would respond to engineer- initiated, control calls for dynamic braking?
It seems to me that the Company would have had a formal protocol in place, calling for that action in a situation where the train is extremely likely to experience a mid-train buckling.
Converting to rear-DPU-only dynamic braking
I don’t think it required perfection in the world to know enough to be very careful with this train. They chose to pass two detectors that were below the threshold of a required stop, but were each showing relatively elevated temperatures on the same bearing. What they surely must have known, but freely ignored, was that the two detectors, in sequence, also showed a progressing trend of rising temperature. They also would have known that if that trend were to continue, the temperature could be easily exceed the maximum permissible limit before the train would arrive at the third detector.
That is exactly what happened. There was nothing unknowable about it. The known trend exceeded the maximum temperature before the train reached the final (third) detector; and the train derailed before it could stop for that third detector as it actively warned them to stop.
The Train Crew - DID NOT KNOW - they had passed two detectors with elevating temperatures. That data was ‘back office’ data and back office personnel had to make decisions on it, not the crew operating the train.
When I say “They chose to pass two detectors…” I am not necessarily referring to the train crew as “They.” I am referring to whoever was in charge of decision making. But your point does raise further questions as to the timeliness of the response of the train operation when facing a life or death emergency such as the one that unfolded.
So you are saying that the crew does not hear any transmission of information from the detectors, when a detector detects it?
What about the stop order they received from the East Palestine detector? Did the crew not hear that until it was first sent to the back office for review? How much time elapsed between time that the East Palestine detector found the failing bearing and the time the crew was notified to stop? News reports make it sound like that was just a matter of seconds.
It seems to me that all of the necessary technology was in place, in perfect operation, and was fully capable of preventing this disaster, if only it had been allowed to do its job.
[quote user=“Euclid”]
BaltACD
The Train Crew - DID NOT KNOW - they had passed two detectors with elevating temperatures. That data was ‘back office’ data and back office personnel had to make decisions on it, not the crew operating the train.
When I say “They chose to pass two detectors…” I am not necessarily referring to the train crew as “They.” I am referring to whoever was in charge of decision making. But your point does raise further questions as to the timeliness of the response of the train operation when facing a life or death emergency such as the one that unfolded.
So you are saying that the crew does not hear any transmission of information from the detectors, when a detector detects it?
What about the stop order they received from the East Palestine detector? Did the crew not hear that until it was first sent to the back office for review? How much time elapsed between time that the East Palestine detector found the failing bearing and the time the crew was notified to stop? News reports make it sound like that was just a matter of seconds.
It seems to me that all of the necessary technology was in place, in perfect operation, and was fully capable of preventing this disaster, if only it had been allowed to do its
I think the DPs are supposed to go to from dynamics to idle if the head end is placed in power. I’ve never tried to do it on purpose. The only time the DPs would stay in dynmaics is during a communication loss between the consists. This I have had some experience with.
Current thinking, by those in charge of our operating practices, is that the train needs to be bunched up as much as possible. We’re even to operate the lead and remote consists in independent mode all the time, no matter what the train make up actually is. I’ve always believed in using the “fence” but not necessarily all the time or on all trains. Even if the remotes could be placed in dynamics, I doubt they would allow it.
Jeff