NTSB report on East Palestine accident

[Overmod]

https://www.ntsb.gov/investigations/AccidentReports/Reports/RIR2405.pdf

[daveklepper]

After receiving the report from the third detector, the3 engineer began slowing the train, intending to stop, using only dynamic breaking. Why not blended braking for a faster, non-emergency, service stop?  Probably because he decided tread braking would heat the wheel even more.

Thanks, Overmod, and comment, please?

[BaltACD]

daveklepper

After receiving the report from the third detector, the3 engineer nbegan slowingv the vtrain, intending to stop, using only dynamic breaking. Why not blended braking for a faster, non-emergency, service stop?  Probably because he cdecided tread braking would heat the wheel even more.

Thanks, Overmod, and comment, please?

Using air brakes on freight cars provides a single point of force against the wheel tread - what makes the brake effective is that the force is acting against the axle of the wheel.  If the axle is, in fact, overheated - the brake application can be the force that causes the axle to snap.  As a engineer, he doesn't know the exact condition of the suspected axle, and thus doesn't want to provide additional force against the axle by using the air brakes.

[Euclid]

I have not yet read the report, but I will be looking for a detailed explanation of each step of the process leading right up to the buckling and piling up of railcars.  This wrecking process is typically referred to as a “derailment,” but derailment is just the first wheel to go on the ground.  It has a cause. 

 

But there is also a process in which the train buckles from rising buff force, and begins a process of jackknifing railcars in a destructive cascade. I call that a pileup. It also has a cause.

 

There can be a long distance between the initiation of the derailment and the onset of the pileup.  The two events can be miles apart, and each having their own cause.  If a train is stopped in time, there may never be a pileup even though the derailment occurred and has run the train on the ground for a long distance. 

[Euclid]

It seems to me that the report is conveying this impression:

 

The detector issued a hot bearing warning to stop.

 

The axle burned off and this initiated the derailment. 

 

The Undesired Emergency (U.D.E.) application of the air brakes occurred as an indication that the train had begun to buckle and pile up. 

 

However, in the report, we are told that the derailment began at least 1,400 feet before any of the above occurred; and during that time, the derailed cars involved were all running in line with the rails, apparently being guided by the rails, but not being borne by them.  So 1,400 feet of cars were running derailed, but not developing any pileup.   

 

Since the burning off of the axle is said to have caused the whole derailment and pileup, where was the axle in this progression when it burned off?

 

If the axle burned off when it was within that initial 1,400 feet of derailed and dragging, or upon first entering that 1,400 foot zone; then it would not have caused the pileup that began after that 1,440 foot zone had been passed.  So then what caused the pileup?

 

And if the axle burned off after passing through the 1,400 foot zone, and then began the pileup, what caused the cars to be dragging on the ground while passing through the 1,400 foot zone when they were derailed, but not piling up?

 

Without clarity on this point, we don’t know what caused the pileup.  We don’t know that it was caused by the hot bearing.  If we don’t know that, then we don’t know what may have prevented the pileup and consequently left the incident confined to just a matter of derailed and dragging.  If there had not been a pileup, there would have been no cost associated with the pileup.  If there had just been enough time left to stop the train, the pileup could have been prevented. 

 

Even though the detector was warning of an impending derailment, we don’t know how much time would have passed before the derailment happened.  All the time that was needed was perhaps another 30-40 seconds to get the train stopped.

 

And also, if the derailed/dragging cars did not cause the pileup, what did?

[BaltACD]

Euclid

... 

And also, if the derailed/dragging cars did not cause the pileup, what did?

The Euclid Mind Derailer.

[adkrr64]

BaltACD

The Euclid Mind Derailer.

 

Sure, blame it on EMD....

[BaltACD]

adkrr64

 

BaltACD

The Euclid Mind Derailer. 

Sure, blame it on EMD....

[BaltACD]

/https://www.ntsb.gov/investigations/AccidentReports/Reports/RIR2405.pdf

Page 49 - Figures 18 & 19 tell you all you need to know about the cause.

Everything else is conjecture about how it got to that state and what happened after.

[Euclid]

BaltACD

/https://www.ntsb.gov/investigations/AccidentReports/Reports/RIR2405.pdf

Page 49 - Figures 18 & 19 tell you all you need to know about the cause.

Everything else is conjecture about how it got to that state and what happened after.

 

The NTSB is not presenting anything as conjecture, so why do you think it is conjecture?

 

I have been looking at Page 49, fig. 18 & 19, and other information in that general area.  In the preliminary details that were being collected, there were all of those photos that are shown here, plus other photos that have been omitted from this final report. 

 

For instance, in that earlier display of photos, there was a photo of the axle with one journal burned off and appearing as burned off axles normally do, almost as if having been cut off with a lathe.  Unless I am missing something, the NTSB now says that the failing bearing, eventually burned the axle off and that began the derailment.  So where is the burned off axle that was shown in those earlier photos a few months ago?

 

In that earlier collection of photos, there also 2 or more photos showing wet grease leaking from bad bearing seals and wetting some of the outside of various metal parts such as the bearing and truck side frame.  Clearly the point was that worn and leaking seals had not been replaced as they should have been.  Therefore, they contributed to the bearing failure. But these photos of leaking grease were on railcars that were in service and not damaged as one would expect if they had been recovered from the East Palestine wreck.  They were close up photos of the trucks with wheels on the rails.  This raises the questions:  Were those photos showing the actual hopper car that derailed in the wreck, but were taken at some time prior to the wreck?

 

Or were these wheels just inserted into this NTSB report as a generic example, just to show what the leaking seals look like?  The same question could be asked about the photo of the burned off axle.  Was this actually from the East Palestine wreck or were the photos just examples unrelated to East Palestine, and illustrating what a burned off axle typically looks like?  Why aren’t there photos of all the truck parts in the exact locations in which they were found right after the train finished piling up?

 

Also, I think it is fair to say that all burned off axles cause a derailment, but they don’t always cause a pileup. 

[tree68]

Euclid

The NTSB is not presenting anything as conjecture, so why do you think it is conjecture?

Because everything about an incident such as this is most often a "most likely" case.  No one saw the axle actually fail - all we have is some heat readings and  doorbell cams.  

Certain  things can come awfully close - they may well have found the spot where the failed truck most likely "dug in," causing the pile-up.  But there are no witnesses that can provide specifics.  No one to say that the axle actually failed right behind Johnson's Hardware Store (fictitious - for sake of discussion).

It's a shame you weren't part of the investigation team.  Expertise such as yours is hard to find...

[BaltACD]

Euclid

... 

Also, I think it is fair to say that all burned off axles cause a derailment, but they don’t always cause a pileup. 

Critical element in whether there is a pile up of one variety or another - what was the speed of the train when the offending car 'hit the ground'.  The irregular nature of the the under car profile makes it more likely than not that 'something' will 'snag' something in the track structure and that snag will create forces unsettling the car in one more planes and that car becomes the 'stopping power' upon which the trailing tonnage at whatever speed is acting against - I feel certain an engineer with lots of time and computer power could create a model of the stresses of each car each second until all the tonnage dissapates its kinetic energy and the entire train comes to a stop.

If the speed is low and the trailing tonnage is negligible then the likelyhood of a major pile up is low.  If the speeds and tonnages are high, the general pile up is highly likely.  If the grade is descending the pile up will tend to be worse than if the grade is ascending or level - the basic physics of mass are at play.

Euc, you need to get away from the keyboard and spend some time on the ground investigating the various aspects of derailments.

[Euclid]

BaltACD

 

 

Euclid

... 

Also, I think it is fair to say that all burned off axles cause a derailment, but they don’t always cause a pileup. 

 

 

Critical element in whether there is a pile up of one variety or another - what was the speed of the train when the offending car 'hit the ground'.  

The NTSB says the hot bearing melted off the axle that was next to the bearing, and the loss of that axle support caused the derailment.  It surely can and does work that way sometimes.  In such a case, the part of the axle is often found on the ground near the beginning of the heap of cars if there is a pileup.  Where, and in what sort of damaged condition was the axle found in the case of this wreck?  There is a lot of evidence left in a wreck like this, and it will disclose many facts.  Apparently, in this case, the burned off axle did not initiate the pileup.  Perhaps other parts of the truck frame assembly broke up and started the pileup.  Axles can also burn off and not cause a pileup.  Also, a train can burn off an axle and pile up for another reason than the burned off axle.  

 

As to the speed of the train, I recall reading that the speed limit for the train when entering the town was 50 mph, and their actual speed of the train was 43 mph.  I have not absorbed all of the accident report yet, but I have found what seem to be some discrepancies between what was said earlier in the investigation and what is now in the final report. 

 

At least, several months ago, the NTSB reported that as the train was entering East Palestine, it was in dynamic braking to reduce the train speed to comply with the lower speed limit when passing through the town.  Suddenly the crew got the warning to stop and inspect the train.  I assume that the crew then knew that a derailment could be imminent. There was probably plenty of discussion about the hot bearing prior to reaching East Palestine. 

 

If a derailment was imminent, there would be great benefit in stopping the train before the imminent derailment happened. They had no idea how much time they actually had.  A derailment might have occurred even before they heard the warning.  It was only the train encountering the detector that determined that a warning was made. 

 

In actuality, a derailment warned of by the detector, may have been 15 minutes or more into the future.  That would have been plenty of time to stop the train with the utmost care.   So what does an engineer do?  Does he gamble that he has time to stop easy, or does he gamble to stop as quickly as possible without causing a derailment? 

 

In this case, when the engineer heard the warning from the detector, he increased dynamic braking.  Of course we don’t know if this increase in dynamic braking created an increase in buff force which buckled the train at the joint with the hot bearing.  But we do that that very soon (less than ½ minute) after increasing dynamic braking, the train actually did pile up.  It did not just put a wheel on the ground.  It began jackknifing and piling up into a heap. 

 

We also know that the hopper car with the failing bearing was only about 25 cars back from the head end power.  That factor alone with a relatively long train, implies a lot of cars pushing against the railcar with the hot bearing as it pushes against the resistance of the head end power applying dynamic braking.

 

I assume that increasing the dynamic braking was intended to minimize stopping time. The point would have been to get stopped before the pileup occurred.  Think of the money that would have been saved if the train got stopped before it piled up.  But, stopping the train quicker would have raised the risk of causing a derailment by excess buff force. 

 

We are now officially told that the train braking had nothing to do with the derailment. We are told that the train derailed when the failing bearing burned off the axle, and then at the same moment, the burned off axle caused the derailment.  All I would like to see is some evidence to back up that assertion. Where is the science?    

[BaltACD]

Euclid

...

We are now officially told that the train braking had nothing to do with the derailment. We are told that the train derailed when the failing bearing burned off the axle, and then at the same moment, the burned off axle caused the derailment.  All I would like to see is some evidence to back up that assertion. Where is the science?    

Had the engineer applied the air brakes, the axle would have rung off once the brake shoe applied pressure to the wheel tread.  Tread air brakes require that the axle be 'solid' in order to allow the pressure of the brake shoe to apply the braking force to the tread.  Once the brake shoe applies force to the wheel tread, it will then displace the wheel if the axle is no longer strong enough to hold the wheel in its designed position.

If you get a Hot Box indiciation from a Defect Detector or from a employee or someone along the right of way - YOU DO NOT USE AIR BRAKES to bring the train to a stop, except as a last resort.

[Euclid]

BaltACD

If you get a Hot Box indiciation from a Defect Detector or from a employee or someone along the right of way - YOU DO NOT USE AIR BRAKES to bring the train to a stop, except as a last resort.

 

If a train has a hot bearing on a railcar, and is in the process of burning off the axle, an air brake application will accelerate the rate of burn-off, as you say.  

 

If a train has a hot bearing that has already burned off an axle, and thus the railcar is dragging derailed; any amount of buff force in the train will tend to buckle the train laterally at the joint of the burned off axle.  

 

Such buff force can be produced by an air brake application; and will be highly likely to be produced by a dynamic brake application made ahead of the derailed dragging car.  The only factor that could prevent buckling in that circumstance of dynamic braking is lateral resistance in the trackwork that is capable of maintaining the derailed car tracking ability.     

 

The railcar with the failing bearing at East Palestine was derailed and dragging for at least 1,400 feet and then something caused the train to buckle at or near the joint with the hot bearing. That buckling began the process of jackknifing and pileup.  It is possible that that derailed and dragging car dug in to the roadbed, and the resistance caused by digging in caused the train to buckle and start the pileup. 

 

If there had been such digging into the roadbed, I would expect that a detailed investigation would easily find the deep furrowing in the roadbed that was plowed up when the car dug in due to its derailed dragging condition. 

 

The ideal braking in this case would have been dynamic braking only on locomotives anywhere behind the hot bearing.  I don’t know if that is possible in today’s practice, but I seems like it would be possible to make practical. 

[BaltACD]

Euc - are you trying to contend that if the engineer had power braked, hard enough to keep the slack stretched throughout the train that there would not have been a multi-car derailment?

[Euclid]

BaltACD

Euc - are you trying to contend that if the engineer had power braked, hard enough to keep the slack stretched throughout the train that there would not have been a multi-car derailment?

 

I would not draw that conclusion because of all the variables.  But yes; I do think that method of braking could have prevented the pileup; but not the way it was configured in this incident.   

 

In any case, there would not be any "power braking."  Power would not be applied as though the objective was keep the train stretched such as when going down a grade. 

 

What would act to keep the train stretched in this case would be only the dynamic braking.

 

And also, it would be only dynamic braking of DPU engines; only those behind the car with the hot bearing. They would be decelerating the train in a way that would keep it stretched through the location of the hot bearing.  There would also be no dynamic braking ahead of the hot bearing car because that would have the opposite effect of having the train bunched behind the head end, and for some distance toward the hind end.  The car with the hot bearing was very close to the head end (I recall about 20 car lengths), so probably would have been in bunched slack if dynamic braking were applied by the head end power.  So, no braking at all at the head end. 

 

This is far different from the way braking was actually applied upon hearing the detector warning.  Most of it was applied to the head end because they had at least two units and they were very near the car with the hot bearing.   

 

Even with the head end dynamic braking having the wrong effect, significant motive power using dynamic braking to resist the momentum from behind the hot bearing car, may have been able to offset the bunching coming from the head end; but only if that trailing DPU was near enough to the hot bearing car.  As I recall, the DPU first behind hot bearing car (there may have been only one DPU in that location) was quite a long distance back.  And it also had the hind end cars behind it, pushing ahead, so unless head end dynamic braking was off, braking this consist from DPU way back in the train may have been futile with the head end dynamic braking bunching the slack near the head end.  

 

And also there is this point:  If dynamic braking was off at the head end and only applied to DPU behind the hot bearing; I would not conclude that braking from a trailing DPU should be agressive for the purpose of stopping as quickly as possible. I would gamble on trading quickest stopping time for minimizing the dynamic brake tension coming forward from behind the hot bearing car.  This gamble would take a little longer to stop the train. 

[zugmann]

nah... nevermind. 

[BaltACD]

Euclid

 

BaltACD

Euc - are you trying to contend that if the engineer had power braked, hard enough to keep the slack stretched throughout the train that there would not have been a multi-car derailment? 

I would not draw that conclusion because of all the variables.  But yes; I do think that method of braking could have prevented the pileup; but not the way it was configured in this incident.   

 

In any case, there would not be any "power braking."  Power would not be applied as though the objective was keep the train stretched such as when going down a grade. 

 

What would act to keep the train stretched in this case would be only the dynamic braking.

 

And also, it would be only dynamic braking of DPU engines; only those behind the car with the hot bearing. They would be decelerating the train in a way that would keep it stretched through the location of the hot bearing.  There would also be no dynamic braking ahead of the hot bearing car because that would have the opposite effect of having the train bunched behind the head end, and for some distance toward the hind end.  The car with the hot bearing was very close to the head end (I recall about 20 car lengths), so probably would have been in bunched slack if dynamic braking were applied by the head end power.  So, no braking at all at the head end. 

 

This is far different from the way braking was actually applied upon hearing the detector warning.  Most of it was applied to the head end because they had at least two units and they were very near the car with the hot bearing.   

 

Even with the head end dynamic braking having the wrong effect, significant motive power using dynamic braking to resist the momentum from behind the hot bearing car, may have been able to offset the bunching coming from the head end; but only if that trailing DPU was near enough to the hot bearing car.  As I recall, the DPU first behind hot bearing car (there may have been only one DPU in that location) was quite a long distance back.  And it also had the hind end cars behind it, pushing ahead, so unless head end dynamic braking was off, braking this consist from DPU way back in the train may have been futile with the head end dynamic braking bunching the slack near the head end.  

 

And also there is this point:  If dynamic braking was off at the head end and only applied to DPU behind the hot bearing; I would not conclude that braking from a trailing DPU should be agressive for the purpose of stopping as quickly as possible. I would gamble on trading quickest stopping time for minimizing the dynamic brake tension coming forward from behind the hot bearing car.  This gamble would take a little longer to stop the train. 

You are so far over your ski's you are out jumping reality and the laws of physics to a crash landing.

[Reading467]

Euclid,  go back to either the STB Public Hearing Docket or the Final Report Docket, download the Event Recorder file and then you can see what actions were taken by the engineer and the corresponding reactions of the DPU (which was located after the 109th car) both before and after the point of derailment.  There are three time frames to examine- the third set has the shortest timeframe and most relevant details     

[jeffhergert]

daveklepper

After receiving the report from the third detector, the3 engineer nbegan slowingv the vtrain, intending to stop, using only dynamic breaking. Why not blended braking for a faster, non-emergency, service stop?  Probably because he cdecided tread braking would heat the wheel even more.

Thanks, Overmod, and comment, please?

 

If you read the report, it states that NS requires a train that gets a warm bearing alarm to start slowing, but not stopping until the train has cleared the detector.  Our instructions are about the same.  Using air brakes instead of dynamics could possibly cause a false reading on another car.  

Our detectors, and others that I've heard over the years, initially don't give what the defect is or it's location.  They only do so once has cleared the detector or the train has stopped on the detector.  Stopping movement on the detector fools it into thinking the train has cleared it.  Then the detector announces type of defect and location(s) in the train.

Most of the time, a detector that checks for hot bearings also checks for other types of defects such as dragging equipment, etc.  That's part of the reason a train is allowed to clear the detector.  Our dragging equipment only detectors do require an immediate stop if an alarm is given, but doesn't give location until stopped.  Knowing where each kind of detector is located is part of knowing one's territory.

I don't agree with not using air brakes to stop the train after receiving an alarm.  The admonishment is to use good train handling procedures.  I understand the argument, but anything that changes the train dynamic quickly or harshly would cause the burned off wheelset to come out of alignment and cause the train to derail.  Excessive dynamics too quickly will increase buff forces.  That could "throw" the wheelset out of line and derail, just as much so as applying the air brakes.  Heat generated from using air won't cause a hot bearing to deteriorate faster.  Heat from brakeshoes would be at the the wheel's outer edges.  A low spot in the tracks or switch frog might cause the alignment to be thrown off just enough.

Many years ago, when I was a conductor, my train had a bearing burn off.  We were going slow through a hand throw crossover after single tracking around a MOW track project.  This required going over a detector slow enough that it was giving trains crossing over false alarms.  Every train ahead of us got a hot box alarm and had to stop and inspect.  They all found nothing.  Our turn and we had the same alarm.  After clearing the detector and receiving the type of defect and location, we stopped and I got off.  The engineer pulled the train ahead.  (Yes, as long as it's not a key train, needed excessive power, no dust or smoke seen from back in the train, and now not operating on concrete ties, we can pull the defect location up to the conductor.)  I had him stop about 20 axles short so I could start inspecting the 20 axles before the indicated location, which was about half a mile behind the enginees.  Using the temp stick, I started checking as I went.  When I got to the indicated bearing, it wasn't there.  The truck frame was dragging on the ground.  When we stopped, the bearing had seized up and stopped rolling, twisting off like a piece of plastic.  you could see this on the axle where the bearing had been.  They sent the wheel truck out (we were about 20 miles from there was one.)  I watched them change out the wheel and then was releived on hours of certain shortly after they were done.

Jeff

[Euclid]

jeffhergert

 

I don't agree with not using air brakes to stop the train after receiving an alarm.  The admonishment is to use good train handling procedures.  I understand the argument, but anything that changes the train dynamic quickly or harshly would cause the burned off wheelset to come out of alignment and cause the train to derail.  Excessive dynamics too quickly will increase buff forces.  That could "throw" the wheelset out of line and derail, just as much so as applying the air brakes.  Heat generated from using air won't cause a hot bearing to deteriorate faster.  Heat from brakeshoes would be at the the wheel's outer edges.  A low spot in the tracks or switch frog might cause the alignment to be thrown off just enough.

 

Jeff

 

Thanks for that explanation.  I think it validates the point I was making yesterday in a few posts above, but to no avail. 

[zugmann]

jeffhergert

If you read the report, it states that NS requires a train that gets a warm bearing alarm to start slowing, but not stopping until the train has cleared the detector.  Our instructions are about the same.  Using air brakes instead of dynamics could possibly cause a false reading on another car.  

A critical alarm requires stopping as soon as it is received.  Even if the train is still on the detector.  Non-critical alarms you clear the detector, as the detector won't even tell you specifics until you do. 

[Euclid]

Reading467

Euclid,  go back to either the STB Public Hearing Docket or the Final Report Docket, download the Event Recorder file and then you can see what actions were taken by the engineer and the corresponding reactions of the DPU (which was located after the 109th car) both before and after the point of derailment.  There are three time frames to examine- the third set has the shortest timeframe and most relevant details     

 

Thanks Reading467 for that information.  I downloaded the 10-page report from the NTSB as shown below.  Most of the report is unclear to me as to how it affected the outcome at East Palestine.  Do have any thoughts or conclusions in that regard?

 

The report contains 5 pages of technical graphs. Most interesting to me is page 3 of 10; D. FIGURES AND TABULAR DATA; second paragraph.  That paragraph is as follows:

 

 

RRD23MR005

LOCOMOTIVE EVENT RECORDERS

Specialist’s Factual Report

May 31, 2023

 

 

 

"The event recorder data from NS 4178 and DPU 4412 indicated at 20:54:24 EST both locomotives went into emergency when NS 4178’s trainline emergency transitioned from off to emergency and DPU 4412’s pneumatic control switch (PCS) transitioned from closed to open.  At the same time of the emergencyapplication, NS 4178 was moving 41 mile per hour (mph) with the dynamic brake in notch 8 (DB8).  Approximately 38 seconds later at 20:55:02, NS 4178 came to a complete stop and had traveled approximately 1,157 feet (ft.) and DPU 4412 had traveled 1,365 ft. in that time.  One second later at 20:55:03 EST, DPU 4412 came to a complete stop and [had?] traveled an additional 3 ft."  

 

 

================================

[Overmod]

Euclid, the emergency occurred due to the derailment.  The thing you want from the event-recorder data in the docket, not the report is the rate of change of the throttle control going into full dynamic.

[BaltACD]

While this is not a hot box induced derailment - it is enlightning as to some of the dynamics that happen when cars hit the ground - for whatever the reason from a train moving at track speed.

https://www.youtube.com/watch?v=LYubpuIe3cw

 

[Euclid]

Overmod

Euclid, the emergency occurred due to the derailment.  The thing you want from the event-recorder data in the docket, not the report is the rate of change of the throttle control going into full dynamic.

 

 

I think what I posted above was what you are looking for.  It was not from the big final report.  It was from a docket list of subjects.  I made this google search:

 

ntsb final report docket east palestine derailment 2023

 

=====================================================

 

It opens to this access:

 

RRD23MR005.aspx

 

NTSB (.gov)

https://www.ntsb.gov › investigations › Pages

 

Feb 3, 2023 — NTSB to Meet and Approve Final Report on Norfolk Southern Train Derailment Investigation in East Palestine, Ohio. NTSB Chair will also hold ...

 

==============================

 

It opens with a short document of about 3 pages on the computer and no actual page numbers.  Then in that document, there is a list of Docket numbers.  I clicked on the first one at the top of the list.  I think I must have searched at the top for:  “EVENT RECORDER FILE” 

 

In any case, that opened another page of Docket list with their numbers with their titles names. 

 

In this large list, I found the following items as items # 16,17, & 18.

 

 

I selected all three from that list, and was able to open them.  They are listed as follows:

 

16  LOCOMOTIVE EVENT RECORDERS SPECIALIST’S FACTUAL REPORT

 

17  LOCOMOTIVE EVENT RECORDERS – ATTACHMENT 1

 

18  LOCOMOTIVE EVENT RECORDERS – ATTACHMENT 2

 

 

 

 

Docket no. 16, SPECIALIST’S FACTUAL REPORT is 10 pages long and is titled:

 

RRD23MROO5

LOCOMOTIVE EVENT RECORDERS

Specialist’s Factual Report

May 31, 2023

 

 

==================================

 

 

I think that is the one you and I were looking for since it is packed with about 5 pages of extremely detailed graphs charting the movement of the train and all of the throttle and DB setting changes; plus all the dimension, and times, speeds, etc.

 

I understand your point above about the information I am seeking not being in the whole final report.  But what I have found is not coming from the whole final report.  And it also appears to be the complete information I was looking for.   

 

I have some other thoughts on this incident.  But if you can come to any conclusions about the effect of the dynamic braking and emergency air brake application, I would be very interested in your thoughts. 

[Reading467]

Euclid,   I printed the Locomotive Event Recorders Specialist's Factual Report in an attempt to compare the lead loco (NS 4178)  with the DPU (4412) parameters during the timeframe starting at 2042 hrs, roughly 12 minutes before the emergency brake application. 

The engineer starting using the dynamics on the lead and 2nd unit (NS 4224) just before 2050 hours.  The DPU's throttle was in notch 8 until 2051:40, returning to idle at 2052:10 (the 10 seconds is an approvimate reading from Figure 4. According to the Operations Group Factual Report, the crew received the HB Warning at 2053:00, based on recordings taken from inside the cab of 4178. The head end DB was in notch 2.  The DPU was at idle. 

The engineer notched the head End DB to 5 and the DPU was also in DB 5 when the emergency application was initiated at 2054:24.  

I believe the answer to your initial question of where the pileup started is in the Track Factual Report, section 3.1.:  "Additional wheel flange derailment markings were observed in the gauge of the track starting about 120 feet west of Pleasant Drive Railroad Crossing at milepost PC 49.2.  These derailment markings were observed to the inside gauge portion of the track and run parallel with the north running rail and extend eastward to where the north derailed wheel strikes the Pleasant Drive Railroad Crossing (Note 6)." 

So, that's the apparent cause of the pile-up: the derailed north wheel of axle L1 of Covered Hopper GPLX 75465 hitting the grade crossing structure after the failed bearing on the other (south) end of axle L1 burned off, thereby separating the train line and causing an emergenecy air brake application.  

[jeffhergert]

zugmann

 

 

jeffhergert

If you read the report, it states that NS requires a train that gets a warm bearing alarm to start slowing, but not stopping until the train has cleared the detector.  Our instructions are about the same.  Using air brakes instead of dynamics could possibly cause a false reading on another car.  

 

 

A critical alarm requires stopping as soon as it is received.  Even if the train is still on the detector.  Non-critical alarms you clear the detector, as the detector won't even tell you specifics until you do. 

 

I admit, I don't know NS procedures, just ours. Nor do I know what alarms might be given. We only have an alarm tone with the words, "defect detected."  Until either clear of a detector or stopped, there is no other info given. If no specific info is given, and it happens, then the entire train on both sides must be inspected.

Again for us, an immediate stop is only required for a defect tone given by a detector that only checks for dragging equipment. We have been having more dragging equipment only detectors beeing put in service, usually at wayside signals, because of the use of concrete ties. Drag a wheel over one and the tie is considered defective. 

Jeff

 

[Euclid]

Reading467

Euclid,   I printed the Locomotive Event Recorders Specialist's Factual Report in an attempt to compare the lead loco (NS 4178)  with the DPU (4412) parameters during the timeframe starting at 2042 hrs, roughly 12 minutes before the emergency brake application. 

The engineer starting using the dynamics on the lead and 2nd unit (NS 4224) just before 2050 hours.  The DPU's throttle was in notch 8 until 2051:40, returning to idle at 2052:10 (the 10 seconds is an approvimate reading from Figure 4. According to the Operations Group Factual Report, the crew received the HB Warning at 2053:00, based on recordings taken from inside the cab of 4178. The head end DB was in notch 2.  The DPU was at idle. 

The engineer notched the head End DB to 5 and the DPU was also in DB 5 when the emergency application was initiated at 2054:24.  

I believe the answer to your initial question of where the pileup started is in the Track Factual Report, section 3.1.:  "Additional wheel flange derailment markings were observed in the gauge of the track starting about 120 feet west of Pleasant Drive Railroad Crossing at milepost PC 49.2.  These derailment markings were observed to the inside gauge portion of the track and run parallel with the north running rail and extend eastward to where the north derailed wheel strikes the Pleasant Drive Railroad Crossing (Note 6)." 

So, that's the apparent cause of the pile-up: the derailed north wheel of axle L1 of Covered Hopper GPLX 75465 hitting the grade crossing structure after the failed bearing on the other (south) end of axle L1 burned off, thereby separating the train line and causing an emergenecy air brake application.  

 

Well, something happened to change the 1400 ft. derailed-dragging phase into the 1600 ft. destructive-buckling-jackknifing-pileup phase.  Snagging something like a switch or grade crossing (as you mention) would be one possibility. However, (unless I am mistaken) the NTSB report does not mention finding any evidence such an event, such as a ripped out grade crossing. There are also other possibilities, including ones related to train handling. 

 

As I recall, the NTSB report says the “Derailment” began with the start of the 1400 ft. derailed-dragging phase.  But they use the term “derailment” to refer to the entire train wreck, including both the derailed-dragging phase and the buckling pileup phase. So the entire train wreck covered a distance of 3000 ft. 

 

The report mentions a variety of events during the derailed-dragging phase such as dropping the bearing race and cone, truck frame sliding on the rail top, skid marks left on top of the rail, wheel flange dents left in tie tops, and burning off of an axle.  However, this does not seem as clearly presented as it could be.  I assume there were no witnesses to any of the events over the entire 3000 ft. range of the wreck.