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Oil Trains Cause Track Defects?

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Posted by Euclid on Friday, November 6, 2015 10:15 AM
Buslist
 
Euclid
 
Buslist
 
Euclid

 

 
Buslist
 
Euclid
Buslist,
So you have tank cars that derail on track irregularities more than any other type of freight car, and your solution is to get rid of track irregularities.  That’s rich.   
 

 

 

No it's called cost effective, understand the concept?

Over and out, you just don't get it!

 

 

 

 

Cost effective?  Who gets to decide what cost is too high and what cost is just right when oil trains are endangering the public?

 

 

 

 

. Another example of how you just don't get it! 

 

 

 

Buslist,
My premise is that if tank cars are unusually prone to derail on track irregularities; and prone to cause track irregularities; it would be cost effective to change tank cars so they are not unusually prone to these problems. 
You are the one who tells me that tank car flexibility/rigidity is accounted for in programs used to design the truck suspension.  If the relatively higher rigidity of tank cars is accounted for in the design of truck suspension, why are tank cars still more prone to derail?
 

 

 

 

Like I said over and out, have better things to do with my time than to try to educate someone that doesn't want to be educated.

 

Buslist,
I ask you a reasonable question, but you say you are too busy.  Maybe someone else will chime in with the answer.  I do thank you for clarifying that that the TSB is correct in their assertion that tank cars cause more track damage, and derail easier on track defects than any other type of rolling stock.  Prior to this information, the consensus here on the forum was that the TSB was wrong in their assertion.
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Posted by Buslist on Friday, November 6, 2015 10:38 AM

Euclid
 
Buslist
 
Euclid
 
Buslist
 
Euclid

 

 
Buslist
 
Euclid
Buslist,
So you have tank cars that derail on track irregularities more than any other type of freight car, and your solution is to get rid of track irregularities.  That’s rich.   
 

 

 

No it's called cost effective, understand the concept?

Over and out, you just don't get it!

 

 

 

 

Cost effective?  Who gets to decide what cost is too high and what cost is just right when oil trains are endangering the public?

 

 

 

 

. Another example of how you just don't get it! 

 

 

 

Buslist,
My premise is that if tank cars are unusually prone to derail on track irregularities; and prone to cause track irregularities; it would be cost effective to change tank cars so they are not unusually prone to these problems. 
You are the one who tells me that tank car flexibility/rigidity is accounted for in programs used to design the truck suspension.  If the relatively higher rigidity of tank cars is accounted for in the design of truck suspension, why are tank cars still more prone to derail?
 

 

 

 

Like I said over and out, have better things to do with my time than to try to educate someone that doesn't want to be educated.

 

 

Buslist,
I ask you a reasonable question, but you say you are too busy.  Maybe someone else will chime in with the answer.  I do thank you for clarifying that that the TSB is correct in their assertion that tank cars cause more track damage, and derail easier on track defects than any other type of rolling stock.  Prior to this information, the consensus here on the forum was that the TSB was wrong in their assertion.
 

 

Once again you have it wrong tank cars are show to cause more damage but are more prone to issues with certain types of irregularities! Will you ever learn to listen?

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Posted by cx500 on Friday, November 6, 2015 10:39 AM

Euclid
 
Buslist
 
Euclid
Buslist,
So you have tank cars that derail on track irregularities more than any other type of freight car, and your solution is to get rid of track irregularities.  That’s rich.   
 

 

 

No it's called cost effective, understand the concept?

Over and out, you just don't get it!

 

 

 

 

Cost effective?  Who gets to decide what cost is too high and what cost is just right when oil trains are endangering the public?

 

 

The railroads get to decide, sometimes with the regulatory authorities looking over their shoulder, and do it on the basis of real knowedge and experience.  Given two choices, replace xx thousand tank cars or worry about perhaps a few miles of track on each railroad, the economic decision is clear.  The track problem is easily manageable by simple and well understood options.  Fix a very specific and localized geometry, or require a speed restriction, or use a different track (or route). 

Tank cars are not the only type of freight cars that have been known to interact poorly with specific track conditions, sometimes within specific speed ranges.  Short ore cars are one, and empty bulkhead flats have also had some problems.  Once the problem was recognized, appropriate operating procedures were modified and eliminated the risk.

John 

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Posted by dehusman on Friday, November 6, 2015 11:00 AM

Buslist
 
Euclid
 
Buslist
 
Euclid
 
Buslist
 
Euclid

 

 
Buslist
 
Euclid
Buslist,
So you have tank cars that derail on track irregularities more than any other type of freight car, and your solution is to get rid of track irregularities.  That’s rich.   
 

 

 

No it's called cost effective, understand the concept?

Over and out, you just don't get it!

 

 

 

 

Cost effective?  Who gets to decide what cost is too high and what cost is just right when oil trains are endangering the public?

 

 

 

 

. Another example of how you just don't get it! 

 

 

 

Buslist,
My premise is that if tank cars are unusually prone to derail on track irregularities; and prone to cause track irregularities; it would be cost effective to change tank cars so they are not unusually prone to these problems. 
You are the one who tells me that tank car flexibility/rigidity is accounted for in programs used to design the truck suspension.  If the relatively higher rigidity of tank cars is accounted for in the design of truck suspension, why are tank cars still more prone to derail?
 

 

 

 

Like I said over and out, have better things to do with my time than to try to educate someone that doesn't want to be educated.

 

 

Buslist,
I ask you a reasonable question, but you say you are too busy.  Maybe someone else will chime in with the answer.  I do thank you for clarifying that that the TSB is correct in their assertion that tank cars cause more track damage, and derail easier on track defects than any other type of rolling stock.  Prior to this information, the consensus here on the forum was that the TSB was wrong in their assertion.
 

 

 

 

Once again you have it wrong tank cars are show to cause more damage but are more prone to issues with certain types of irregularities! Will you ever learn to listen?

 

This is exciting, I think we are about to find out what the maximum number of nested quotes is possible in this forum's software.  I say it will only be one more after this since that would squeeze the original quote down to about one character wide, making it virtually unreadable, possibly the kindest thing that could happen to the thread.

Dave H. Painted side goes up. My website : wnbranch.com

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Posted by Buslist on Friday, November 6, 2015 11:22 AM
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Posted by Euclid on Friday, November 6, 2015 11:25 AM
 
 

[/quote]

cx500
 
Euclid
 
Buslist
 
Euclid
Buslist,
So you have tank cars that derail on track irregularities more than any other type of freight car, and your solution is to get rid of track irregularities.  That’s rich.   
 

 

 

No it's called cost effective, understand the concept?

Over and out, you just don't get it!

 

 

 

 

Cost effective?  Who gets to decide what cost is too high and what cost is just right when oil trains are endangering the public?

 

 

 

 

The railroads get to decide, sometimes with the regulatory authorities looking over their shoulder, and do it on the basis of real knowedge and experience.  Given two choices, replace xx thousand tank cars or worry about perhaps a few miles of track on each railroad, the economic decision is clear. 

The economic decision may be clear, but you seem to carry both choices to the extreme.  Replace thousands of cars; or worry about a few miles of track?  How do you come up with just a few miles of track?  And why is there a need to replace thousands of tank cars? 
How about just making the cars with a slightly modified truck suspension so they don’t cause problems on thousands of miles of track?  That is what I would do. 
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Posted by Euclid on Friday, November 6, 2015 11:37 AM
Buslist,
It sounds like the cause was the worn condition of the constant contact side bearings.  I assume that this was a defect that should have taken the car out of service until repaired.
The issue with tank cars that you have explained is a design problem affecting every car, and not the result of a defect that happens to show up through operation.   
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Posted by Murphy Siding on Friday, November 6, 2015 12:06 PM

dehusman
 
Buslist
 
Euclid
 
Buslist
 
Euclid
 
Buslist
 
Euclid

 

 
Buslist
 
Euclid
Buslist,
So you have tank cars that derail on track irregularities more than any other type of freight car, and your solution is to get rid of track irregularities.  That’s rich.   
 

 

 

No it's called cost effective, understand the concept?

Over and out, you just don't get it!

 

 

 

 

Cost effective?  Who gets to decide what cost is too high and what cost is just right when oil trains are endangering the public?

 

 

 

 

. Another example of how you just don't get it! 

 

 

 

Buslist,
My premise is that if tank cars are unusually prone to derail on track irregularities; and prone to cause track irregularities; it would be cost effective to change tank cars so they are not unusually prone to these problems. 
You are the one who tells me that tank car flexibility/rigidity is accounted for in programs used to design the truck suspension.  If the relatively higher rigidity of tank cars is accounted for in the design of truck suspension, why are tank cars still more prone to derail?
 

 

 

 

Like I said over and out, have better things to do with my time than to try to educate someone that doesn't want to be educated.

 

 

Buslist,
I ask you a reasonable question, but you say you are too busy.  Maybe someone else will chime in with the answer.  I do thank you for clarifying that that the TSB is correct in their assertion that tank cars cause more track damage, and derail easier on track defects than any other type of rolling stock.  Prior to this information, the consensus here on the forum was that the TSB was wrong in their assertion.
 

 

 

 

Once again you have it wrong tank cars are show to cause more damage but are more prone to issues with certain types of irregularities! Will you ever learn to listen?

 

 

 

This is exciting, I think we are about to find out what the maximum number of nested quotes is possible in this forum's software.  I say it will only be one more after this since that would squeeze the original quote down to about one character wide, making it virtually unreadable, possibly the kindest thing that could happen to the thread.

 

  We'll find out.

Thanks to Chris / CopCarSS for my avatar.

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Posted by Murphy Siding on Friday, November 6, 2015 12:10 PM

Cool

Murphy Siding
 
dehusman
 
Buslist
 
Euclid
 
Buslist
 
Euclid
 
Buslist
 
Euclid

 

 
Buslist
 
Euclid
Buslist,
So you have tank cars that derail on track irregularities more than any other type of freight car, and your solution is to get rid of track irregularities.  That’s rich.   
 

 

 

No it's called cost effective, understand the concept?

Over and out, you just don't get it!

 

 

 

 

Cost effective?  Who gets to decide what cost is too high and what cost is just right when oil trains are endangering the public?

 

 

 

 

. Another example of how you just don't get it! 

 

 

 

Buslist,
My premise is that if tank cars are unusually prone to derail on track irregularities; and prone to cause track irregularities; it would be cost effective to change tank cars so they are not unusually prone to these problems. 
You are the one who tells me that tank car flexibility/rigidity is accounted for in programs used to design the truck suspension.  If the relatively higher rigidity of tank cars is accounted for in the design of truck suspension, why are tank cars still more prone to derail?
 

 

 

 

Like I said over and out, have better things to do with my time than to try to educate someone that doesn't want to be educated.

 

 

Buslist,
I ask you a reasonable question, but you say you are too busy.  Maybe someone else will chime in with the answer.  I do thank you for clarifying that that the TSB is correct in their assertion that tank cars cause more track damage, and derail easier on track defects than any other type of rolling stock.  Prior to this information, the consensus here on the forum was that the TSB was wrong in their assertion.
 

 

 

 

Once again you have it wrong tank cars are show to cause more damage but are more prone to issues with certain types of irregularities! Will you ever learn to listen?

 

 

 

This is exciting, I think we are about to find out what the maximum number of nested quotes is possible in this forum's software.  I say it will only be one more after this since that would squeeze the original quote down to about one character wide, making it virtually unreadable, possibly the kindest thing that could happen to the thread.

 

 

 

  We'll find out.

 

 

  It only  loses some of it's meaning, but the post does have something of an artistic value about it.

Thanks to Chris / CopCarSS for my avatar.

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Posted by Norm48327 on Friday, November 6, 2015 1:22 PM

Hey Bucky,

You gonna tell us your qualifications or not? We're all ears. One can't help but think that because you ignore the question that you have no qualifications to offer. That leaves your "experience" and opinions on a subject open to suspicion.

Norm


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Posted by Euclid on Friday, November 6, 2015 1:30 PM

Open to suspicion?  Oh, Norm, say it isn't so!

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Posted by Euclid on Friday, November 6, 2015 1:35 PM
Norm48327
 
Euclid
that tank cars are inherently more prone to derailments than any other type of rolling stock.

 

But you have been saying that all along, together with the position that oil tank cars cause track damage that causes derailments.

You once claimed that I have no knowledge of your experience or expertise in railroading. You are right on that score, and judging from your repeated "yes but" expertise on your part is lacking. Would it be too much to ask for some credentials rather than simply listening to your inane and uninformed rants.?

 

Norm,
I have NOT been saying all along that tank cars are inherently more prone to derailments than any other type of rolling stock. 
The above quote that you appear to attribute to me is my words, but I was citing the comments by the TSB.  The quote is not me saying that tank cars are inherently more prone to derailments than any other type of rolling stock. 
What I have been doing all along is questioning the role of fluid slosh and weight shifting on oil unit trains.  But that is only me raising the possibility for consideration.  I have never asserted that it is happening to any significant degree. 
Why worry about my credentials?  If you don’t have the expertise to know whether I am right or wrong, I can’t see you accepting it on faith, based on what I claim as credentials.   Just a little common sense goes a long way in judging what people say.
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Posted by Norm48327 on Friday, November 6, 2015 1:45 PM

Euclid
Why worry about my credentials? If you don’t have the expertise to know whether I am right or wrong, I can’t see you accepting it on faith, based on what I claim as credentials. Just a little common sense goes a long way in judging what people say.

Your refusal to answer leaves only one conclusion; that you have no qualifications. Therefore your posts have no credibility.  You are blowing smoke and other posters have no reason to believe you know of what you speak.

Euclid
I have NOT been saying all along that tank cars are inherently more prone to derailments than any other type of rolling stock.

I suggest you go back and reread your own posts. You keep saying wrong things and then deny that. You are in need of some reality checks. Yes, some of us think you are nothing more than a troll.

Norm


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Posted by Euclid on Friday, November 6, 2015 1:54 PM
Norm48327
I suggest you go back and reread your own posts. You keep saying wrong things and then deny that. You are in need of some reality checks. Yes, some of us think you are nothing more than a troll.
 

Norm,
I suggest you seek some anger management counseling. 
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Posted by Norm48327 on Friday, November 6, 2015 2:05 PM

Euclid
 
Norm48327
I suggest you go back and reread your own posts. You keep saying wrong things and then deny that. You are in need of some reality checks. Yes, some of us think you are nothing more than a troll.
 

 

Norm,
I suggest you seek some anger management counseling. 
 

It has nothing to do with anger Bucky. I'm not the only one who is fed up with your inane ramblings. If you can show us some qualifications and experience we may take you seriously.

Norm


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Posted by schlimm on Friday, November 6, 2015 2:08 PM

Amid all the shouting, one thing seems clear: none of the usual suspects  on this forum have the self-stated credentials or expertise to be in a position to go beyond or dispute what actual experts at the TSB and NTSB have said in the various reports.  And that means myself, Euclid, PDN, Dave Husman, Norm, buslist, wizlish or any others I have overlooked.  

C&NW, CA&E, MILW, CGW and IC fan

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Posted by Euclid on Friday, November 6, 2015 2:21 PM
Norm48327
 
 If you can show us some qualifications and experience we may take you seriously.
 

Norm,
You are taking me too seriously already. 
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Posted by Euclid on Friday, November 6, 2015 2:30 PM
schlimm

Amid all the shouting, one thing seems clear: none of the usual suspects  on this forum have the self-stated credentials or expertise to be in a position to go beyond or dispute what actual experts at the TSB and NTSB have said in the various reports.  And that means myself, Euclid, PDN, Dave Husman, Norm, wizlish or any others I have overlooked.  

 
Well, I was originally skeptical of the TSB conclusion that tank cars are more prone to causing track damage, and to being derailed by track defects.  But after having this confirmed by Buslist and Dave Husman, I will accept the TSB conclusion.  Tank rigidity is the problem, and apparently nobody has solved that problem yet.  So, obviously this is why so many oil trains are derailing. 
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Posted by Norm48327 on Friday, November 6, 2015 2:45 PM

schlimm

Amid all the shouting, one thing seems clear: none of the usual suspects  on this forum have the self-stated credentials or expertise to be in a position to go beyond or dispute what actual experts at the TSB and NTSB have said in the various reports.  And that means myself, Euclid, PDN, Dave Husman, Norm, wizlish or any others I have overlooked.  

 

Schlimm,

My credentials are that of an aircraft mechanic (Airframe & Powerplant with Inspection Authorization). Everything I know about railroading, which, in reality, is little, I have learned from a few friends who are actually employed by railroads.

I participate here with the hope of learning more about the art and science of the rails; not to be fed tons of uninformed speculation. The real railroaders have given up and left the forum because one poster says they don't know what they are talking about. Quality information is lost and replaced qith uninformed opinion.

Norm


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Posted by schlimm on Friday, November 6, 2015 2:51 PM

Norm48327
The real railroaders have given up and left the forum because one poster says they don't know what they are talking about.

I think there are more than a few "real railroaders" on here quite regularly: Don Oltmann, BaltACD, Jeff Hergert, Larry (Tree), Ed Blysard, to mention just a few.

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Posted by Paul of Covington on Friday, November 6, 2015 8:23 PM

   I don't remember who said what or who claimed that who said what any more in this thread, but I'm getting a kick out of it.

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Posted by Murphy Siding on Friday, November 6, 2015 8:43 PM

Paul of Covington

   I don't remember who said what or who claimed that who said what any more in this thread, but I'm getting a kick out of it.

 

Didn't you say that earlier? Stick out tongue

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Posted by Randy Stahl on Saturday, November 7, 2015 7:29 AM

schlimm

Amid all the shouting, one thing seems clear: none of the usual suspects  on this forum have the self-stated credentials or expertise to be in a position to go beyond or dispute what actual experts at the TSB and NTSB have said in the various reports.  And that means myself, Euclid, PDN, Dave Husman, Norm, buslist, wizlish or any others I have overlooked.  

 

Shlimm, I am also a career railroader. I have worked in most of the operating departments and I have a degree in electrical engineering (high power) . I do not claim to be an expert on this topic but I have some experiences that qualify me to make educated guesses including operating loaded oil trains.

 

Anyhow, the point I wanted to make is that even though I have some credentials, I still learn from the posts made by yourself and others here. At the very least they make make me rethink things that I thought I already know about. Many times a post here will start a discussion among the other rail professionals that I know. So even Bucky , although his posts can be tedious sometimes have causes some very interesting conversations at work.

As for the topic , I still haven't seen enough good evidence to support the TSB theory. All trains damage the track, thats why we have MOW departments.

I think all of my replies on this topic have been along the same line of thinking, I have an open mind just show me some real evidence!

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Posted by dehusman on Saturday, November 7, 2015 8:06 AM

schlimm
 
Norm48327
The real railroaders have given up and left the forum because one poster says they don't know what they are talking about.

 

I think there are more than a few "real railroaders" on here quite regularly: Don Oltmann, BaltACD, Jeff Hergert, Larry (Tree), Ed Blysard, to mention just a few.

I've said I work for a railroad many times.   I'll let you dig through the 8000+ posts to find it. 

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Posted by Euclid on Saturday, November 7, 2015 8:11 AM
So, to answer the question posed in the title of this thread, the final conclusion of this thread is as follows:

1)   Oil unit trains do cause more track damage than all other types of trains. 

2)   Oil unit trains are more prone to derail than all other types of trains.

 
The reason for these facts is that tank cars lack the flexibility needed to supplement the wheel load equalization that occurs with all other types of freight cars.  Therefore tank cars have insufficient wheel load equalization.    
Insufficiently loaded wheels cause the remaining wheels to be overloaded, and this causes track damage, defects, and irregularities.  
Insufficiently loaded wheels are more prone to derailment than are properly loaded wheels when passing over track damage, defects, and irregularities.
This conclusion has been confirmed by the TSB of Canada, and nobody participating in this thread discussion disagrees with it. 
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Posted by Paul of Covington on Saturday, November 7, 2015 8:13 AM

Devil

Murphy Siding
 
Paul of Covington

   I don't remember who said what or who claimed that who said what any more in this thread, but I'm getting a kick out of it.

 

 

 

Didn't you say that earlier? Stick out tongue

 

    Murphy, why are you claiming that I said that, and what are your credentials for saying so?Devil

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Posted by Norm48327 on Saturday, November 7, 2015 8:16 AM

dehusman
I've said I work for a railroad many times. I'll let you dig through the 8000+ posts to find it.

Dave,

To clarify; my statement was in reference to those who threw up their hands in disgust and have left the forum. As I recall, there were several.

Norm


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Posted by Norm48327 on Saturday, November 7, 2015 8:21 AM

Euclid
This conclusion has been confirmed by the TSB of Canada, and nobody participating in this thread discussion disagrees with it.

Then it would seem logical that there is no need for further posts in this thread, but I'm certain you will clarify your position.

Norm


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Posted by dehusman on Saturday, November 7, 2015 8:31 AM

Euclid
This conclusion has been confirmed by the TSB of Canada, and nobody participating in this thread discussion disagrees with it.

Euclid has spoken!  So shall it be written!

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Posted by Wizlish on Saturday, November 7, 2015 9:29 AM

Euclid
So, to answer the question posed in the title of this thread, the final conclusion of this thread is as follows:

1) Oil unit trains do cause more track damage than all other types of trains.

2) Oil unit trains are more prone to derail than all other types of trains.

The reason for these facts is that tank cars lack the flexibility needed to supplement the wheel load equalization that occurs with all other types of freight cars. Therefore tank cars have insufficient wheel load equalization. Insufficiently loaded wheels cause the remaining wheels to be overloaded, and this causes track damage, defects, and irregularities. Insufficiently loaded wheels are more prone to derailment than are properly loaded wheels when passing over track damage, defects, and irregularities. This conclusion has been confirmed by the TSB of Canada, and nobody participating in this thread discussion disagrees with it.

I hope you all are proud of what you have done to poor Euclid.  Looking back I am surprised at how often he had made quite cogent requests for clarification, mostly to be met by a combination of hectoring disdain and perhaps intentional misunderstanding of what he actually needs to understand the answers.  The red herring about qualifications or credentials hasn't helped the discussion at all,except perhaps to drive away anyone who has technical competence and a respect for civility at the same time.

The issue with 'torsional rigidity' of tank cars supposedly causing an increased propensity for actual derailments ought to be easily-enough checked, as the code for it is already in programs like NUCARS, Vampire, ADAMS and so forth.  It should be possible for someone here who works with these programs and understands software to tell us exactly what the magnitude and type of the 'corrections' for stiffness, fundamental frequencies, etc. are, and then determine whether this is of sufficient magnitude (personally, I think it is not, but take that as no more significant as starting a scientific inquiry with the null hypothesis) to produce sufficient wheel (not axle, not truck frame, not spring) unloading ... or other forces in the car/truck dynamical system, perhaps induction of hunting or lozenging? ... that would produce a statistically-significant increase in the observed propensity to derail.

There's a very common parallel to this in dynamic augment in steam locomotives.  Because the axle load is so substantial on most American road power, even high levels of reciprocating imbalance do not produce 'bouncing' of the drivers, or even unloading of the axle sufficient to produce uncontrollable wheelslip (we can leave duplex-drives aside for now).  I cannot believe that anyone with even a smidgen of engineering experience would equate the added torsional stiffness of a tank car over a typical closed car like a covered hopper with the wheel loading that the weight of the car imposes -- through the springs and the longitudinal equalizing action of the sideframes -- on the wheeltreads.  But as I keep saying, it doesn't matter what I think, it matters what the math says.  And fortunately the math works whether or not the person using it has a BSeng degree or PE cert.

To Norm in particular,and to those who work regularly with vehicle-dynamics software: yes, your credentials may apply in the present context.  There were people who thought Chapelon was unqualified to discuss steam because his degree was in EE.  There's not much to be said for that.  It is certain to me, however, that an aircraft powerplant mechanic is likely to be far more qualified to understand an engineering issue than, say, someone with a medical degree.

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