I know there must be a few possible causes, but which one or two account for most derailments? The reason I ask: these oil train derailments seem to be an almost weekly occurrence now. Two weeks ago it was CSX and this week its CN (again). Is it an operational problem (train crew not running the train properly) or is it mostly a track issue or a combination of issues?
As with most things like this, it depends. In the case of derailments, it depends on who answers the question.
If an operations guy answers, it was clearly a track or equipment failure. If an MoW guy answers, the crew was running too fast or it was an equipment failure. And, finally, if an MoE guy answers, the track failed or the crew was running too fast.
And that, friends, is why the 1st three people to arrive at a derailment (after the crew) are representatives of each of those three departments.
But politics aside there are probably (in keeping with Pareto’s Law) a very few causes that lead to the vast majority of derailments. Maybe 80% of derailments are caused by broken rails. Or maybe 80% of derailments are caused by defective rolling stock components. Or maybe its train handling. I don’t know.
I am not sure of the distribution of causes, but there are many, many causes. I don’t believe that one cause stands out as a major problem area. I am not sure how many derailments get fully resolved as to the finding of cause. Maybe most of them do. Maybe somebody can provide a source for the information. The news always assures us that the cause is under investigation.
Here are derailment causes that come to mind:
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Broken rail
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Broken rail joint
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Broken wheel
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Broken wheel flange
You forgot meteor strikes, acts of terrorism, rabid bear attacks, and Big Foot. I know there are many possible causes; however, there are probably only one or two causes that are responsible for 80% of derailments… After every derailment there’s an investigation, what do these investigations show? I would bet that one or two causes dominate over the others… If they fixed those then the weekly derailments and resulting fire clouds would go away for the most part.
I would guess that the more frequent “causes” are likely the least spectacular. Such as deviation in the guage allowing a wheel to touch down.
For all the work that gets done maintaining track, I sure see a lot of unusual wear and tear type deterioration.
I recall recently seeing a molten suplhur train where the roadbed was so badly beaten up that the track would raise completely off the ground a good foot, in between the wheelsets. The rails would come up with the ties still hanging from them, under each car as the train passed. Then I noticed that not ALL ties were coming up with the rail, just most of them. And hitting pretty hard when the rails came down.
You start missing many ties and maintaining guage would appear challenging.
Just my anecdotal observation.
On my railroad “picking a switch” was not a valid cause to submit on a
derailment report. It was the result of something else such as a
switch out of alignment or it could be broken switch point. The bosses
would want to know why the derailment happened at the switch.
Is mishandling of the train ever cited as a cause for derailment? Last night on the news they interviewed a “safety expert” who suggested that railroads need to use their top locomotive engineers on these trains. His comments implied that these oil train derailments are the fault of poor train handling.
Yes, improper train handling is a valid cause for some derailments.
The expert implied… should we assume he has a collection of downloads and evidence to support his assertion ?
I assert that many of these trains are being run with the assistance of the “leader” system and I have not seen one finding laying fault on the engineer (save one).
Randy
One “cause” can be dismissed immediately: Trains do not JUMP the track, although it’s possible for a wheel to be forced over the rail head for a number of possible reasons.
Tom
You may be right that one or two causes predominate, but I tend to doubt it. There is a long list of obscure causes that pop up one by one. They derail trains every day.
So the list of causes that I provided is not far fetched at all. They happen in rotation day in and day out.
Neverthe less, your question about more widesread, common causes is interesting. So I look forward to hearing what others think.
I agree… not far fetched. Was just funin with you. But it seems to be a law of nature that a few inputs produce the vast majority of outputs. In the average workplace 20% of the workers produce 80% of the output. 80% of all car accidents are the result of 20% of the driver population etc. 80% of all wealth is concentrated among 20% of the population. So one might expect that 80% of derailments are caused by 20% of all likely causes. Maybe 80/20 is the wrong ratio, the point is that all possible causes aren’t equally likely contributors… there are likely to be one or two or five maybe that are responsible for the vast majority of derailments.
Euclid- ice, ice, ice. At least its seasonal…
It depends on how fine you want to cut the data. If you just go track caused, human caused, equipment caused, or environmental caused, yes you can get down to one major cause. It also depends on what you are considering as derailments. One wheel down in a yard track or just FRA reportable? Probably track and human caused are the two biggest.
If you really care this is all on the FRA’s website.
Mac
See link @ http://www.fra.dot.gov/Page/P0001
Very ‘searchable’
Trains do jump the track. The PRR had two K4’s eastbound on the down hill grade above Horseshoe curve leave the inside track on the and cleared the outside track many years ago due to not controlling the downhill speed. It never touched the outside track.
It is rare and involves a lot of speed.
RR
The three major causes of derailments are human factor related, and mechanical failure and track defects.
The first consists of things like lining a switch under a car, not properly lining a switch/failing to secure the handle in the latch, attempting to couple cars with mis-aligned drawbars and couplers and excessive coupling speed.
Following those, impropper train movement, like shoving blind, and improper clearance, (cornering cars) exceeding track authority/running a signal.
Failure to secure cars/train, while a big issue in the news, accounts for a small but very “public” amount of derailments caused by roll aways.
Mechanical failure can consist of a whole slew of things from failed bearings, (not that common anymore, current story included) brake rigging failure, also not all that common, wheel defects, everything from cracks to sharp flanges to excessive flat spots and, even more rare, bolster/truck failure.
Last is track defects, stripped joint bars, not an issue on most Class 1s main lines as they are almost all welded rail.
Worn frog points, and broken rail, (several causes from failed subsurface/fatigue) to wide gauge, caused by sun kinks, (expansion) pull aparts, (contraction) failed ties.
If you question concerned the recent “oil train” derailments, I believe you will find almost all of these were caused by track or wheel defects.
MOW forces are streched pretty thin right now, the last summer and winter have both been somewhat extreme.
The commodity itself, crude oil, has been hauled since the early 1900s…the recently raised “sloshing” debate