Longer Trains Cause More Derailments

[Euclid]

Here is some news about this question.  Does anybody actually know the answer?  Railroad labor advocacy seems to frequently cite this increase of danger with monster trains.  However, that view is understandable because everyone agrees that monster trains reduce crew costs, and thus cause a loss of jobs.   The media obviously jumped onto that bandwagon in response to the East Palestine wreck, which was then affirmed by the Springfield, OH wreck.   

 

This latest news suggests that engineers may need more training to know how to operate the longer trains. 

 

 

https://fortune.com/2023/04/28/railroad-derailment-long-trains-federal-regulators-problem-contributor/

 

 

The feds are warning railroads that their love of long trains is leading to horrible accidents and derailments—but they’re not doing anything about it yet

 

 

 

[Fred M Cain]

Well, aside for the serious issue of slack action on super long trains, there is also the mathematical law of averages.

If there is a chance, however small, that a defective car can cause a derailment in a 50-car train, those chances double when you go to 100 cars.  Then, they double AGAIN when you go to 200 cars.  I think the NS derailment in Springfield, OH, involved a train with 200+ cars.

My hunch is that there must be a way to make long trains operationally safe.  We just need to find a way to "push the right buttons" so to speak.

[SD70Dude]

An excerpt from the following report:

"In 2005, the TSB conducted a safety issues investigation involving an extensive analysis of train derailments and their relationship to bulk tonnage traffic.  Loaded high-capacity rail cars in unit trains pose special problems to main lines where weak track conditions (ties, ballast, and subgrade) may be common. A unit train consist is usually uniform; that is, all cars are of the same design and loading, with the car trucks and car bodies responding more or less as one unit. Therefore, each rail car on the train responds to track irregularities in the same manner as the previous car, leading to cumulative impacts at irregularities that the train encounters in the track structure. Trains with numerous rail cars of the same design and with high load capacity provide the track little or no opportunity for elastic recovery during their passage. As a result, high-capacity unit trains can hasten permanent and usually non-uniform track deformation."

https://www.tsb.gc.ca/eng/rapports-reports/rail/2020/r20w0102/r20w0102.html

Long, heavy trains will have greater in-train and train-track forces than shorter trains.

[dpeltier]

SD70Dude

An excerpt from the following report:

"In 2005, the TSB conducted a safety issues investigation involving an extensive analysis of train derailments and their relationship to bulk tonnage traffic.  Loaded high-capacity rail cars in unit trains pose special problems to main lines where weak track conditions (ties, ballast, and subgrade) may be common. A unit train consist is usually uniform; that is, all cars are of the same design and loading, with the car trucks and car bodies responding more or less as one unit. Therefore, each rail car on the train responds to track irregularities in the same manner as the previous car, leading to cumulative impacts at irregularities that the train encounters in the track structure. Trains with numerous rail cars of the same design and with high load capacity provide the track little or no opportunity for elastic recovery during their passage. As a result, high-capacity unit trains can hasten permanent and usually non-uniform track deformation."

https://www.tsb.gc.ca/eng/rapports-reports/rail/2020/r20w0102/r20w0102.html

Long, heavy trains will have greater in-train and train-track forces than shorter trains.

The 2005 study itself is here:

https://www.tsb.gc.ca/eng/rapports-reports/rail/etudes-studies/siiR0501/siir0501.html

You have quoted the 2020 report accurately, but the 2020 report refers misleadingly to the 2005 study. The 2005 study does not purport to show that the statement is true, it just sets forth the statement itself, without references or support. It is not a conclusion of the 2005 study, it is a hypothesis that is then used to justify the conclusions of that same study, and if that sounds messed up... it gives you a pretty good idea of how well that 2005 study was put together. It's junk. But that doesn't stop a careless person from citing it in a future report.

Dan

 

[dpeltier]

Euclid

Here is some news about this question.  Does anybody actually know the answer?

 

Short answer? No. The best available evidence I can find is a paper written by my good friend Darwin Schafer back when we were grad-school office mates:

https://railtec.illinois.edu/wp/wp-content/uploads/pdf-archive/TRBDarwin---The-Relationship-Between-Train-Length-and-Accident-Causes-and-Rates.pdf

It notes that the traditional model is to divide accident causes into train-mile-related causes and car-mile-related causes, and if you believe in that model then increasing train lengths will always increase the derailment rate per train-mile and decrease the derailment rate per car-mile (i.e. decrease the derailment rate overall). The paper observes in passing that certain categories - notably train-handling - don't always fit neatly into either category, and warns that you can't conclude from this study that longer trains reduce derailments over all (especially for trains > 150 cars, which were not well represented in this 2007 study). It's also worth noting that several "train-mile-related" causes such as passing red signals or exceeding speed restrictions have been reduced in importance by the widespread use of PTC, so theoretically that dimishes the safety advantage of longer trains.

That said - there certainly is not any study out there to suggest that longer trains result in MORE derailments. The labor leaders making this claim are spouting pure BS with nothing to back them up.

FRA thinks that some recent derailments may be due to train makeup procedures, which are kind of indirectly related to train length. But even if that's the case, there's reason to doubt that this small number of accidents would overcome the safety benefit of having fewer (i.e. longer) trains out and about and getting into trouble.

And if you step back and use a different safety metric - lives lost, rather than number of derailments - there is absolutely no question in my mind that longer trains save lives. That is because the vast majority of all lives lost in railroad accidents occur in grade-crossing and trespasser collisions, which aren't affected at all by train length. Longer trains means fewer trains means fewer deaths, period.

Dan

[Euclid]

When I asked the question in the thread title, these are the terms and details of that question:

 

Compare an example of two trains:

 

TRAIN #1 is 150 cars long with distributed power optimally arranged throughout the train.  It has a mixed consist, which is made up of empties and loads, which are distributed throughout the train according to commonly accepted good principles.

 

TRAIN #2 is 250 cars long with distributed power optimally arranged throughout the train.  It has a mixed consist, which is made up of empties and loads which are distributed throughout the train according to commonly accepted good principles.  The additional 100 cars of this train are similar in weight and distribution to the cars in TRAIN #1.

 

Both trains are tested on the same sample of average track with frequent curves and a variety of grades.  Ambient conditions are average and identical for both test trains.  Operating speeds are identical for both trains.  Both trains are operated by the same engineer who is well qualified.

 

QUESTION:  What is the comparative likelihood of each train derailing due to excessive in-train buff and draft forces that cannot be adequately controlled and limited by the train handling of the engineer?

 

The purpose is to compare these two trains to determine if the buff and draft forces of each train are identical, or if those forces are higher in the 250-car train compared to the 150-car train.    

 

The ultimate purpose of the comparison is to determine whether the longer train has a higher probability of derailing due to having higher buff or draft forces. 

 

Another way to look at the question:  As the train length increases, so too does the distributed power and dynamic braking.  It may be that the power and braking continues to be capable of avoiding excess buff and draft forces as the train length increases.  Or it may be that the ability of power and braking reaches a plateau where there is no longer sufficient control to limit buff and draft forces enough to prevent derailments. 

 

If it is found that the longer train does have a higher probability of derailing due to these higher forces, that would lead to inquiry as to what can be done to reduce those forces with the 250-car train to make them the same as the with the 150-car train.  This could look at the distribution of power and its dynamic braking, engineer operating techniques, and computer control by a program of the train optimum train make-up, route geometry, weather conditions, and other variables. 

 

The point of this explanation is just to show the objective, but not to actually design the testing for the effects of the in-train forces.  The tests imply a need for measuring the in-train forces and the time and location of their occurrence.  This would seem to require using actual revenue trains with strain gages on their couplers.  The logistics of that seem to be impossible.   

 

The FRA is asking railroads to upgrade crew training to keep up with increasing train lengths.  This would require research to discover what is needed in the upgraded crew training. 

[blue streak 1]

I have had a problem of it just being length of trains.  All buff and draft forces are due to how many couplers are on a train.  Each coupler allows for some slack. Also any slack action from cushioned cars.  Now what about a 15 - 20k IM train made up of 3 and 5 packer well cars.?  It might have as few couplers as maybe a 5000 - 8000 regular manifest train.

[Overmod]

blue streak 1

I have had a problem of it just being length of trains.

The physics of train length and handling aren't part of the actual discussion, any more than actual roller-bearing safety through increased carman inspections is.  That we see so much reference to not blocking crossings and keeping more people mandated for various operations... carefully engineered to involve "safety"... gives it away.

Now, mandating a limit in train length between DPU units... that would make sense.  So would regulation of train makeup, which so many railroads have demonstrated lethal incompetence in arranging.  As you note, long consists of well cars, even baretable, have far less 'unsafe' potential than uncoordinated long-travel cushion cars.  (One of the fun things advanced ECP makes possible, although lost on the Feinberg contingent, is that individual braking rates can be modulated during an application to control likely intercar and interblock dynamics.)

[Euclid]

blue streak 1

I have had a problem of it just being length of trains.  All buff and draft forces are due to how many couplers are on a train.  Each coupler allows for some slack. Also any slack action from cushioned cars.  Now what about a 15 - 20k IM train made up of 3 and 5 packer well cars.?  It might have as few couplers as maybe a 5000 - 8000 regular manifest train.

 

It would be nice if someone created a graphic computer model that demonstrates the actions of so-called “in-train forces” and how they act in a long freight train as it travels over varying track geometry at varying speeds.

 

There is a lot of talk that the advent of much longer freight trains comes with the danger of more high speed derailments.  They say this is obvious because the longer trains are heavier and thus more likely to derail.  But why should that be just a forgone conclusion?  Railroad labor advocacy claims this to be a fact as though it should be obvious.  Apparently, so does the FRA. 

 

I would conclude that slack is not the primary creator of buff and draft forces.  The primary creator is locomotive tractive effort and braking.  There would be buff and draft in a train even if it had solid drawbars and no slack at all. 

 

But what slack does allow is the buff and draft forces being able to change one joint at a time, and thus accumulate their force so that when it is finally arrested against a hard stop, it contains the kinetic energy of a long string of cars, rather than of just one car.  And if those cars happened to have slack bunched, they will collide with all of their kinetic energy being released at once.

 

So say you have a solid wall across the track and rolled one car into it at 5 mph. The wall and car would absorb the impact from one car moving 5 mph.  But if you have 50 cars rolling at 5 mph, and if their slack is bunched and the first car hits the wall, the wall and first car would absorb the impact from 50 cars moving at 5 mph.  How much damage would that do to the first car?  It would probably cause a derailment starting with the first car.

 

However, in most cases, you will not have a condition where the effect of a solid, stationary wall exists because the train is moving and once it stops, all slack force issues cease.  All of the conditions for derailment-causing excess forces will depend on the following factors: 

 

Slack positions

Distribution of loads and empties

Train speed

Track curves and grades.

Distribution of power and braking

 

 

Since proper Distribution of power and braking will manage the other conditions of slack positions, distribution of loads and empties, train speed, and track curves and grades; the Distribution of power and braking can be increased to naturally match an increase in train length.   Under that assumption, trains length can be increased indefinitely without any added risk making derailments more likely due to increasing in-train forces. 

 

So the only question I see is whether Distribution of power and braking be adequately established and controlled. 

[BaltACD]

Euclid

blue streak 1

I have had a problem of it just being length of trains.  All buff and draft forces are due to how many couplers are on a train.  Each coupler allows for some slack. Also any slack action from cushioned cars.  Now what about a 15 - 20k IM train made up of 3 and 5 packer well cars.?  It might have as few couplers as maybe a 5000 - 8000 regular manifest train. 

It would be nice if someone created a graphic computer model that demonstrates the actions of so-called “in-train forces” and how they act in a long freight train as it travels over varying track geometry at varying speeds.

 

...

It has already been done.  I was given a opportunity by one of the Senior Road Foremen of Engines about 30 years ago to operate one of CSX's Engineer Training Simulators.  Simulator could be programmed, on demand, to run any Subdivision on the property and any train that existed on the CSX Car & Train Database could be loaded - with the engine consist that operated that train IRL.

When making throttle and/or brake inputs there was a graphic representation of the various intrain forces that were being generated with the territory being negotiated.  At the time, CSX's maximum train length on most territories was 9000 feet as this was well before the implementation of PSR principles.

[jeffhergert]

Within the last year or so, UP announced a computer program that can run a train's route and show where problems might happen.  I don't think it is used to reposition cars, just give them an advance heads up about where something might happen.

Just looking at a train list is sometimes enough because it's obvious that things should be changed.  A few times I know where a crew raised objections and were told to go with it.  Then the train derailed on that crew's portion of the run.  (Funny how even though the crew told the FRA investigators that fact, it didn't make it into the FRA accident report.)

DP is not the panacea it's made out to be.  Yes they do help.  All our trains over 10000 feet need a mid train DP.  Longer trains over a certain weight threshold need a mid and rear DP.  Some still get torn up, sometimes into three or four  pieces.  Sometimes it's a problem with the DP that causes the initial action that results in a train breaking into two.

Not all trains are the same.  One of our mixed manifests is often 60 or 70 % cushioned drawbars.  We have a couple that have few of the cushioned drawbars.  Both types can often be in the 12000 to 15000 foot range.  Guess which type is likely to have problems out on the road. 

We've had some intermodals up tp 18000 feet.  Many are often in the 12000 to 15000 foot range.  They normally don't have many problems.  (Other than open container doors.)  They are relatively light and don't have cushioned drawbars.  They aren't bad to run.

Regarding air brake usage,  Most trains I get I only have to use air when stopping.  Eastbound, except for light trains, like empty unit trains, I will need to use air once for sure to control speed.  That's coming down the short 1.25% grades coming down into the Missouri River valley.  There's two other areas eastbound where I may need to use air to maintain speed, but even in those places if I have enough good dynamics I won't need to use air. 

The FRA wants more crew training.  Maybe that's not where the problem is.  Crews run these things everyday.  They get to know what works and what doesn't.  Maybe railroad management needs more training in making up trains.

Jeff

[Euclid]

 

Generally, ECP brakes have been promoted on the basis that they provide much shorter stopping distance of freight trains.  This claim was always quantified by the percentage reduction of stopping distance.  However, to the best of my knowledge, this claim was never fully qualified in public promotion.  Such qualification would have stipulated that the claim only applied to brake “Service” applications because with brake “Emergency” applications, the stopping time/distance reduction was negligible.  

 

Here is an example of that claim from The Railway Technical Website:

 

http://www.railway-technical.com/trains/rolling-stock-index-l/train-equipment/brakes/electro-pneumatic-brakes-d.html

 

“With the new responsiveness of ECP braking, braking distances will be reduced. A range of 30 - 70% reduction has been quoted. This will allow shorter stopping distances and will, in turn, allow higher speeds.”

 

This specification makes no mention of the fact that it only applies to airbrake “Service” applications, while it is the “Emergency” application that demands relatively short stopping distance.  That is because that application is for situations that spontaneously pop up often when a train is too close to stop with a "Service" application,  or an “Emergency” application.  Fundamentally, emergency stopping requires the quickest stopping response. 

 

This fact took the wind out of the sails for the mandate for certain tank cars to be equipped with ECP brakes about 6 years ago.  In any case, the industry is vehemently opposed to ECP brakes because it requires that all locomotives and cars must be converted to remain compatible within the standardized interchange pool.

 

So the industry argued against ECP brakes only on the basis of the reduced stopping distance, but they did not bother to mention the misleading premise that had always surrounded the issue as I mention above.  Instead the railroads only based their objection on the fact that very few accidents are caused by brake failure.  They completely sidestepped the advantages of ECP mitigating in-train forces. 

 

And in the time since dodging that ECP mandate, the railroads have fallen in love with monster trains, which feature a centerpiece of potential, excessive in-train forces.  And the industry cannot dis-prove that excess in-train forces are causing more derailment with the longer trains because nobody has done enough testing to find the answer.

 

However, with ECP brakes, all in-train forces can be virtually eliminated.  Actually it is a far greater feature benefit than improved stopping distance.  So monster trains and ECP brakes is a marriage made in heaven.  Now, unless the high in-train forces issue can be disproven, the only argument opposing EPC is the cost of the added safety.  

[BaltACD]

jeffhergert

...

The FRA wants more crew training.  Maybe that's not where the problem is.  Crews run these things everyday.  They get to know what works and what doesn't.  Maybe railroad management needs more training in making up trains.

Jeff

On 'my' division of CSX, there were a number of TTSI's that related to train make-up that limited the positions of various cars/types when built into trains.  Many of these restrictions were related to the trailing tonnage that could be in the train behind such cars.  My division did include mountainous territory with a high degree of curvature in surmounting those grades.  These restrictions had been developed from the examination of causes of derailments over the years - learned in 'blood'.  While these restrictions were second nature to the yardmasters on the division who made every effort to comply with the restrictions - my divisions restrictions were not uniformly enacted across the company as a whole.  Flatlanders did not have the restrictions, even though they were building trains that would operate through the territory that occasioned the restictions.  A company failure in my mind.

[Euclid]

Here is what the FRA has found in their preliminary investigation of the March 4, 2023, Springfield, OH derailment on the NS Railway:

 

Quoting from this link:

 

https://www.railwayage.com/wp-content/uploads/2023/04/Safety-Advisory-2023-03.pdf

 

“The train consisted of three head-end locomotives and two mid-train DPUs, with one head-end locomotive offline. The train was traveling on an ascending 0.6% grade with the heavier part of the consist (the back end) on a 0.7% downhill grade. The weight was mostly concentrated at the head and rear ends of the train.

 

During the incident, dynamic braking was applied only to the head-end locomotive consist, while the DPUs were idle, making the train function like a conventional train.

 

The derailment happened at the sag between ascending and descending grades, with short, empty rail cars designed to ship coiled steel being the first to derail.

 

Buff forces peaked as the downhill portion of the train ran-in, causing the derailment of cars 70 through 72 (the short coil cars) and the subsequent pile-up.

 

The train was classified as a key train,7 with 28 loaded hazardous materials (hazmat) cars distributed throughout. No hazmat cars derailed. FRA’s investigation into this incident is currently ongoing, but preliminary indications show excessive buff force due to train makeup and train handling are the primary causes of the incident.”

 

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

 

What about the loose wheels which NW found and concluded were the cause of the wreck?

[Euclid]

I conclude that ultra-long trains made possible by distributed power, have disproportionably more complex and more violent train dynamics than relatively shorter trains such as less than 100 cars.  With the longer trains comes a large variety of random slack force patterns that can be difficult to understand and control.  These conditions found in the ultra-long trains cause derailments due mostly to hard slack run-ins. 

 

The core issue is not that locomotive engineers fail to understand what train handling is needed to offset these slack issues.  The real problem is that the core issues of long train slack dynamics are not sufficiently understood by the ones who decide to run the ultra-long trains.  The most attention to the problem has been focused on train makeup, which has always been recognized as being critical even before the advent of ultra-long trains.  But train makeup alone does not seem adequate to solve the greater tendency for derailments that comes with ultra-long trains.  Therefore, I don’t think that optimum train makeup will solve the problem.  It will help, but it does not go far enough.  

 

So, to the question of whether ultra-long trains cause derailments, I conclude that the answer is YES.   There is also a growing movement that concludes likewise.  The FRA says the solution is for locomotive engineers to solve the problem by keeping up with the demands of increasing train length practice.  That seems like a predictable response.  The FRA does not have a solution, but they are sure there is one.  So they conclude that the only challenge will be for operating people to apply the solution. 

 

Oddly enough, there is a solution right in plain sight.  The basic problem is train braking.  And this circles back to our old friend, ECP brakes.  Back when ECP first emerged, it came with several valuable new features such graduated release, lower in-train forces, and shorter stopping distance.  People naturally think of stopping distance reduction when they consider brake improvements.  Indeed, it is shorter stopping distance that always increases safety, and better safety always sells.  So the champion feature of ECP brakes was hailed to be shorter stopping distance. 

 

Yet this was extremely misleading and almost dishonest.  Trains basically have two different brake systems with two different names which are “Emergency” and “Service.”  While ECP impressively reduces stopping distance, it does so only with the Service application, where there is very little need for reduced stopping

distance.  It is only the Emergency application that has a profound need for shorter stopping distance, and for that, ECP offers almost nothing. 

 

The real champion of ECP features is:  LOWER IN-TRAIN FORCES. And this is also the most direct and meaningful benefit needed to prevent derailments with ultra-long freight trains.

 

ECP provides this feature by moving all brake shoes against all of the wheels simultaneously, and with equal pressure.  Fundamentally, this eliminates the reason for slack to run in or out.  However in a practical sense, even with simultaneous application, brakes will vary in stopping power due to the weight of the car.  So car load sensors must be included with ECP.

 

There is also the issue of brake and wheel wear, which can cause the braking response to vary.  This may require new regulations to improve maintenance on brake shoes and wheels for cars that will qualify for ultra-long train service. 

 

But of course this solution to the ultra-long train derailment problem will be fiercely opposed by the railroad companies because of their dread of ECP brakes.  It is only the social impact of train disasters written in blood that will push this forward.  But the industry would give up the long trains if it would avoid ECP.     

[oltmannd]

Euclid

Here is some news about this question.  Does anybody actually know the answer?  Railroad labor advocacy seems to frequently cite this increase of danger with monster trains.  However, that view is understandable because everyone agrees that monster trains reduce crew costs, and thus cause a loss of jobs.   The media obviously jumped onto that bandwagon in response to the East Palestine wreck, which was then affirmed by the Springfield, OH wreck.   

 

This latest news suggests that engineers may need more training to know how to operate the longer trains. 

 

 

https://fortune.com/2023/04/28/railroad-derailment-long-trains-federal-regulators-problem-contributor/

 

 

The feds are warning railroads that their love of long trains is leading to horrible accidents and derailments—but they’re not doing anything about it yet

 

 

 

 

It's gonna be more territory specific than train consist specific.  FEC could run just about anything, anywhere, anytime no sweat.  Horseshoe curve?  CSX Boston Line?  We'd have to talk...

[Euclid]

With the current trend of ultra-long trains, I understand that the preferred method of braking is not air brakes, but rather dynamic brakes.  Dynamic brakes apply only on the locomotive units.  When the units used to be all on the head end, the use of dynamic brakes limited train the length (and was limited by train length) because their application caused all of the trailing tonnage to run in against the locomotive units, whereas air braking restrained that run-in force by applying brakes to all the cars in addition to the locomotive units.   

 

However, with the advent of locomotive units being distributed throughout the train, this distributed power also distributed the dynamic braking.  It still had the disadvantage of slack run-in resulting from no braking on the cars, but only on the locomotives.   However it did offer the advantage of at least spreading out the dynamic braking even though it left no direct braking on the individual cars.  

 

Distributed power was a new development that eliminated the need to place all the power on the head end.  So by spreading out the power in the train, distributed power allowed longer trains without the danger of pulling them in two; a danger that is greatest with all of the power pulling from the head end.

 

DP also allowed increasing the use of dynamic brakes in lieu of air brakes because DP also spread out the braking force of dynamic brakes in addition to spreading out the motive power.  Distributing dynamic braking allowed longer trains without the danger of buckling them; a danger that is greatest with all of the power applying dynamic braking from the head end.   

 

HOWVER, although spreading out dynamic braking was a step in the right direction for braking longer trains without the danger of buckling, it still applied braking only to the locomotives, which resulted in the trailing un-braked cars running in to the locomotive when dynamic braking is applied.  All it does is limit the number of cars running into a locomotive power unit by dividing the train up into distributed power sections.  So each section has fewer cars running into its locomotive than would be the case will all of the power on the head end.  Nevertheless, the run-in of un-braked cars is more likely to cause train bucking than run-in of cars during braking with air brakes.  Ideally, when the train is divided into distributed sections of power and dynamic braking, it would also be divided into distributed sections of air braking. 

 

Distributing the air braking would prevent the brakes from applying serially from the head end to the hind end, which takes considerable time in the case of a “Service” application, which is used for routine train handling.  If this improvement were possible, it would reduce the need for dynamic braking with its fundamental disadvantage of applying only on the locomotives.   However, this improvement for air braking is not possible with conventional pneumatic controlled pneumatic braking (PCP).  However it is a function feature of ECP braking.  In any case, there is no practical way to implement it with current practice.  So with each individual locomotive power set dividing the long train into sections, each section acts like one train being braked by only the locomotive. 

 

I suspect the presence of excess in-train forces in ultra-long trains arises from excess reliance on dynamic braking even though it is made safer by the distribution of dynamic braking into blocks throughout the train.  However, despite that benefit, dynamic braking still suffers from the disadvantage of being confined to only the locomotive wheels and not to the railcar wheels. 

 

Then when you add the changing and opposing grades, which naturally occur in greater number under longer trains, the variation in car type and weight, and the random and complex patterns of slack surge that result; you get an overall train behavior that is impossible to predict by existing means of evaluation.    

 

References that I find concur with my conclusion on that point.   That is why I suggest a means to actually measure buff and draft force on each coupler joint in a test train that duplicates an actual revenue train.

 

[Overmod]

Euclid

I suggest a means to actually measure buff and draft force on each coupler joint in a test train that duplicates an actual revenue train.

Probably be easier to equip them with magnetic or clamp-on battery-powered accelerometers, and store the results with GPS location and timestamp, then stream all the results wirelessly.  Assign an IoT address to each one to keep them definitively apart.

Where the effort ought to be placed is better control of the 'fence' activity in Locotrol so that any trailing power modulates its dynamic correctly for the part of its train between nodes.  Without that, any long train on an irregular profile might indeed be another Springfield cocked and unlocked...

You'd use exactly the same set of accelerometers, feeding into one of the train management programs, to figure out what that ought to be, and what permanent methods should be implemented (probably as an AAR standard) to deal with it.

[tree68]

It's probably already been done, virtually - ie, on a computer.

Acceleration, deceleration, and buff forces can easily be simulated, and I'm pretty sure most profiles have been recorded as well.

And probably for less money than it would take to equip some 200 cars.

 

[BaltACD]

tree68

It's probably already been done, virtually - ie, on a computer.

Acceleration, deceleration, and buff forces can easily be simulated, and I'm pretty sure most profiles have been recorded as well.

And probably for less money than it would take to equip some 200 cars.

In the early 1990's CSX had a Simulator for Engineers that married the calculation of in train forces by using the data of actual trains that had been operated and the ability to operate that train of data over any of the territory CSX was operating.

Of course in the 1990's Distributed Power was not on CSX's horizon.

I am certain that in the 21st Century, the CSX Simulator does replicate that various operating modes with DPU in one or more locations within specified trains; with those location(s) able to be manipulated on instructor demand.

In my use of the simulator what was missing was the actual physical impacts from slack action - the buff and draft kicks in the pants.

[Euclid]

Overmod

 

 

Euclid

I suggest a means to actually measure buff and draft force on each coupler joint in a test train that duplicates an actual revenue train.

 

 

Probably be easier to equip them with magnetic or clamp-on battery-powered accelerometers, and store the results with GPS location and timestamp, then stream all the results wirelessly.  Assign an IoT address to each one to keep them definitively apart.

 

Where the effort ought to be placed is better control of the 'fence' activity in Locotrol so that any trailing power modulates its dynamic correctly for the part of its train between nodes.  Without that, any long train on an irregular profile might indeed be another Springfield cocked and unlocked...

You'd use exactly the same set of accelerometers, feeding into one of the train management programs, to figure out what that ought to be, and what permanent methods should be implemented (probably as an AAR standard) to deal with it.

 

I agree that what is needed is an easy, quick way to equip a long test train with sensors that would record drawbar forces in relation to variable conditions such as train length, train makeup, track grades and curves, train speed, brake operation, and throttle settings.  I don’t think it would be practical to attempt to simulate all of the combinations of conflicting in-train forces that need to be evaluated.  If they have all of that gathered and evaluated now, as some may claim, then why are they not finding that trains are destined to derail?

 

I doubt the railroads would program simulators that show that derailments can be caused by excess buff forces in their ultra-long trains.  But I suspect that if they had real world data, it would show that in-train forces associated with these trains will derail them under certain conditions.  Indeed, that is the conclusion of the FRA and unions.  And there is mounting empirical evidence of the correlation.

 

Not only is real world testing needed, but it also needs to be done by independent technicians and experts.  It has to be done with real world trains, and it has to be presented in terms that are objective enough that the results cannot be spun. 

 

The real world is showing strong evidence that ultra-long trains are developing in-train forces that are causing derailments.  It has to be determined whether these accidents are being caused by operator error in train handling or by erroneous conclusions about the risks resulting from excess in-train forces. 

 

If the cause is operator error, new training is necessary.  If the cause is excess in-train forces, a combination of remedies must be called for and mandated if necessary.   These remedies would include limiting train length, the use of train make-up programs, and ECP brakes. 

[BaltACD]

Euclid

... 

I doubt the railroads would program simulators that show that derailments can be caused by excess buff forces in their ultra-long trains.  But I suspect that if they had real world data, it would show that in-train forces associated with these trains will derail them under certain conditions.  Indeed, that is the conclusion of the FRA and unions.  And there is mounting empirical evidence of the correlation.

 

...

Your lack of knowledge of railroad operations and supervision is SHOUTING.

[Euclid]

BaltACD

 

 

Euclid

... 

I doubt the railroads would program simulators that show that derailments can be caused by excess buff forces in their ultra-long trains.  But I suspect that if they had real world data, it would show that in-train forces associated with these trains will derail them under certain conditions.  Indeed, that is the conclusion of the FRA and unions.  And there is mounting empirical evidence of the correlation.

 

...

 

 

Your lack of knowledge of railroad operations and supervision is SHOUTING.

 

Well if you have the knowledge; show me the use of computers to model the in-train forces in a 250-car train with suitable distributed power and best train handling practice in moderately hilly terrain, at typical road speeds.

 

Also, if the industry has this capability, why aren’t they using it to predict derailments caused by in-train forces?   If they are doing that, why are these derailments occurring? 

[BaltACD]

Euclid

 

BaltACD 

Euclid

... 

I doubt the railroads would program simulators that show that derailments can be caused by excess buff forces in their ultra-long trains.  But I suspect that if they had real world data, it would show that in-train forces associated with these trains will derail them under certain conditions.  Indeed, that is the conclusion of the FRA and unions.  And there is mounting empirical evidence of the correlation. 

... 

Your lack of knowledge of railroad operations and supervision is SHOUTING. 

Well if you have the knowledge; show me the use of computers to model the in-train forces in a 250-car train with suitable distributed power and best train handling practice in moderately hilly terrain, at typical road speeds.

 

Also, if the industry has this capability, why aren’t they using it to predict derailments caused by in-train forces?   If they are doing that, why are these derailments occurring?  

All I can say is that such modeling was taking place when I was still employed.  That being said I have been retired since December 2016 and subsequently PSR attacked my former employer in the form of a dying EHH and virtually all Operating Management was replaced by EHH cronies - with all that being the case I have no idea what form of modeling is taking place.

I do know that when I was working the CSX Train Handling Rule and divisional employee timetable special instructions had a number of restrictions on how to build trains and how much trailing tonnage was allowed before a helper or DPU was required.

Personal observations from some local incidents AFTER EHH and PSR were thrust into operations, indicated to me, that some of the restrictions that were in effect when I was working did not appear to be in effect from the incidents (derailments) that happened.

[tree68]

There's rules, then there's compliance with the rules...

[BaltACD]

tree68

There's rules, then there's compliance with the rules...

And there is Supervision to ensure compliance.

Without proper Supervision, you don't have much.  Without a rules compliant culture you have even less.

[zugmann]

tree68

There's rules, then there's compliance with the rules...

It's not like a RFE has to pull physical tapes anymore.  All the stuff has instant triggers, instant downloads, instant reviews. 

[oltmannd]

Euclid

 

 

BaltACD

 

 

Euclid

... 

I doubt the railroads would program simulators that show that derailments can be caused by excess buff forces in their ultra-long trains.  But I suspect that if they had real world data, it would show that in-train forces associated with these trains will derail them under certain conditions.  Indeed, that is the conclusion of the FRA and unions.  And there is mounting empirical evidence of the correlation.

 

...

 

 

Your lack of knowledge of railroad operations and supervision is SHOUTING.

 

 

 

 

Well if you have the knowledge; show me the use of computers to model the in-train forces in a 250-car train with suitable distributed power and best train handling practice in moderately hilly terrain, at typical road speeds.

 

Also, if the industry has this capability, why aren’t they using it to predict derailments caused by in-train forces?   If they are doing that, why are these derailments occurring? 

 

They do have modeling tools.  They do use them to set rules for train make-up and territory. 

They are often used retrospectively to analyze derailments. 

They are generally difficult to use and tough to deploy as tools for train consist management.  Car geometry plays a big role as does ROW geometry and in-train forces.

[oltmannd]

Euclid

 

 

BaltACD

 

 

Euclid

... 

I doubt the railroads would program simulators that show that derailments can be caused by excess buff forces in their ultra-long trains.  But I suspect that if they had real world data, it would show that in-train forces associated with these trains will derail them under certain conditions.  Indeed, that is the conclusion of the FRA and unions.  And there is mounting empirical evidence of the correlation.

 

...

 

 

Your lack of knowledge of railroad operations and supervision is SHOUTING.

 

 

 

 

Well if you have the knowledge; show me the use of computers to model the in-train forces in a 250-car train with suitable distributed power and best train handling practice in moderately hilly terrain, at typical road speeds.

 

Also, if the industry has this capability, why aren’t they using it to predict derailments caused by in-train forces?   If they are doing that, why are these derailments occurring? 

 

Or, why haven't these derailments stopped happening. 

RRs have, for a very long time, built trains the would derail if they went into emergency in just the right spot. Once in a blue moon, they would and did!

[tree68]

oltmannd

Or, why haven't these derailments stopped happening. 

As I noted earlier, there's rules, and there's following them.  

Too, consider the problem of combining proper placement with blocking.