FIVE WAYS THE LAC-MÉGANTIC CRASH CHANGED HOW WE SHIP CRUDE BY RAIL

[Euclid]

I would expect that the criminal trial will pursue the question of whether securement was routinely compromised on the MM&A as a part of company culture, and the engineer was just following that culture.  By charging two not only the engineer, but also two of his supervisors, it opens the door to pursuing the question of whether the securement fault was only a one-time violation by the engineer; or whether he acted accordance with some type of company sanctioned procedure.

However, it is disconcerting that in the news of criminal charges, there is no mention by the police of a push-pull test being performed or omitted. It leaves me wondering if the police even understand that element of the securement rule.

When you have special instructions on a railroad that talk about requiring a minimum number of handbrakes at different locations and with different tonnages, it would be easy to perceive that as being the only requirement.  It would be extremely easy and likely for an outsider to interpret it that way.  It might even be possible for a railroad culture to interpret that way with the aid of a little rationalization.  Just the sound of the special instruction leaves the impression that it fully addresses the securement requirement, when it is actually only a part of the requirement.           

[edblysard]

Your last paragraph is without a doubt the most honest and intelligent comment any of you folks have made about this.

Although I don’t know of any engineer or conductor who would leave a train up there without the proper handbrake test, obviously this is what happened, but I am pretty sure he, (Harding) felt it was secure as he left it, after all, he went to the bottom of that same hill, took a room and went to sleep, with the train he left aimed right at himself.

The GCOR, Norac book of rules, and the Canadian rule book all have a procedure on securing a train, they all say the same basic thing, they all insist on a test and all include the phrase “sufficient number of brakes to secure against movement”…if the rule had been followed, we wouldn’t have anything to discuss.

Granted, there are extenuating circumstances and events beyond the control of the engineer, but still, had the rule been followed, nothing the fire department could have done, short of releasing the hand brakes, would have caused the run away.

Yup, the train could have been left down in town, but I bet the city didn’t want it there, they are noisy and smoke and create a nuisance…blocking the main was not a issue, it was blocking the same main up on the hill.

Did the FD screw the pooch by shutting off the lead unit?

Probably didn’t help matters much.

Should the dispatcher have sent a maintenance guy out to fix the lead unit before it caught fire?

Yup, but they didn’t, they sent a MOW guy out to see if it was really burning….lots of events that could have changed the entire outcome, any one could have prevented it, but the basic screw up was not setting enough handbrakes and not testing the ones that were set.

The securement rule wasn’t followed, simple as that.

All the inventions, EPC brakes, split rail derails, berms, wheel chocks, or the Force would have made no difference without the test.

[Euclid]

schlimm

Again, note that operating personnel on this thread appear to have differing opinions.   That implies pretty strongly that the best procedure is hardly a uniform, settled issue.

The Lac Megantic discussion always leads into the topic of air brakes because they played a role in that wreck.  In my opinion, the discussion of airbrakes is nearly beyond the ability to communicate on a forum because of the amount of detail that comes into play, and the common failure to fully define ones terms in the discussion.  It leads to constant miscommunication and misinterpretation. 

Adding to the problem of discussing airbrakes relating to the Lac Megantic wreck is that nobody knows exactly how the airbrakes were applied or why they released, so there are multiple possible scenarios.  So you are right that many knowledgeable people disagree about the role of airbrakes in the MM&A runaway.  There are many differing opinions, as you say.

However, you are asking about the proper train securement procedure, and that has nothing at all to do with airbrakes.  Airbrakes only come into play in the Lac Megantic wreck discussion because they were relied upon illegally as a substitute for the proper securement procedure.  So all of the disagreement over the role of airbrakes does not mean that there is disagreement over the proper securement procedure.  I do not recall any disagreement over the issue of proper securement. 

I should have also mentioned in my explanation of proper securement above, that there is usually a minimum number of handbrakes required at various locations and various train tonnages and makeup.  That minimum takes precedence over a successful push-pull test. 

In the case of the Lac Megantic runaway, it has been reported that the engineer did not set the minimum number of required handbrakes.  All of the news that I have seen on the Lac Megantic wreck has focused on the minimum number of required handbrakes at Nantes.  I have not seen anything reported stating that a push-pull test was required, nor whether one was performed.  On one hand, that is moot because the engineer failed to set the minimum number required regardless of any results from a push-pull test.

However, it would be possible to set a number of handbrakes that passed a push-pull test, and yet have that number fall below the required minimum.  If that is what the engineer did, it would reflect quite a bit differently on him; as opposed to failing to set the minimum and also failing to perform a push-pull test.  So the complete lack of mention of anything to do with a push-pull test seems to leave the story somewhat inconclusive. 

Also interesting is that the news has reported what other engineers have described doing to secure trains.  They talked about a prescribed number of handbrakes, and none that I have read about have mentioned doing a push-pull test.  Leaving out that component of securement Rule 112 violates the rule. 

So, overall, that suggests to me that there may have been a culture of omitting the push-pull test and relying on the precedent of trains not running away in the past with a certain number of handbrakes applied.  Or there may have been a culture of relying on airbrakes to hold a train, and downplaying the role of handbrakes as being only a backup.    

[blue streak 1]

Will Davis gives us a very good idea of failure analysis.  Limited exposure to it in job certainly says he is correct.

[schlimm]

Euclid

schlimm

A quick check on posts suggests the need for a uniform policy on safety with a stopped and shut down Bakken train.   There are several different opinions expressed on here as to the proper procedures.

There is a uniform policy, and it is actually pretty simple.  The discussion of what happened to the air brakes on the ill-fated MM&A oil train is anything but simple, however that has nothing whatsoever to do with proper securing of the train.

To achieve proper securement, you set hand brakes until you have enough set to hold the train with air brakes completely released on the train and the locomotive. The achievement of sufficient hand brake resistance is determined by a push pull test with the locomotive, plus a sense of judgment that the enough resistance has been achieved to prevent the train from rolling away once it is deemed to be secured.  That is basically Rule 112 in Canada.

What I am waiting for is the final report by the TSB of Canada and their analysis of the securement.  A few years ago, they basically said that Rule 112 is impossible to comply with on high grades.   

Again, note that operating personnel on this thread appear to have differing opinions.   That implies pretty strongly that the best procedure is hardly a uniform, settled issue.

[Euclid]

schlimm

A quick check on posts suggests the need for a uniform policy on safety with a stopped and shut down Bakken train.   There are several different opinions expressed on here as to the proper procedures.

There is a uniform policy, and it is actually pretty simple.  The discussion of what happened to the air brakes on the ill-fated MM&A oil train is anything but simple, however that has nothing whatsoever to do with proper securing of the train.

To achieve proper securement, you set hand brakes until you have enough set to hold the train with air brakes completely released on the train and the locomotive. The achievement of sufficient hand brake resistance is determined by a push pull test with the locomotive, plus a sense of judgment that the enough resistance has been achieved to prevent the train from rolling away once it is deemed to be secured.  That is basically Rule 112 in Canada.

What I am waiting for is the final report by the TSB of Canada and their analysis of the securement.  A few years ago, they basically said that Rule 112 is impossible to comply with on high grades.   

[MidlandMike]

dehusman

Just remember not all crude is the same, the ONLY crude that has had problems is the Bakken crude.  The crude from every other formation that railroads have been hauling for over  a century does NOT have those same problems. 

There is also a problem with Congress and the FRA just throwing solutions out there just because they are cool and high tech without thinking about whether they would have solved a problem.  ECP wouldn't have prevented Lac Megantic, it wouldn't have prevented Casselton, it wouldn't have prevented the release in Kentucky.

While the Bakken is highly flammable, it is not unique.  The Canadian TSB report on Lac Magantic analysed the tank car contents for flammability, and showed how it was comparable to other very light crudes such as condensates.  There is also potential for condensates to be rail hauled, as there is a big demand for them as dilutant for tar sands oil.  While oil has been hauled for over a hundred years, it has been a couple of generations since it was a significant source of rail traffic.  Even then there were crude tank car explosion/fires as shown by a photo in a previous Trains forum on CBR a few months ago.  As I recall it was near Columbus OH in about the 1940s.  No crude oil should be thought of as an inert product.

As has been pointed out by other posters, railroads have gone thru similar problems with propane, ethanol, and other more explosive/flammable cargo.  I believe that railroads will get thru this too.

[Ulrich]

Maybe they could do the crew change at the bottom of the hill instead of at the top? 

[Euclid]

zugmann

Euclid

  Maybe the handbrakes could be retained for that setout, but securement could just as well be accomplished by use of the single control, pneumatically powered brake lock to secure the car with air brakes set fully and mechanically locked in the set condition, just like securing a whole train.

Again - don't handbrakes set brakes mechanically?  I'm still lost with your definitions and nuances.

I am talking about a powered brake locking system for every car in a train.  It is set on or off from a single control inside the locomotive cab.  You set the air brakes, and then set the brake lock to locking position.  It mechanically locks the air brakes with a spring powered lock.  The lock is released by compressed air, and set by exhausting air. 

Just to be clear, once the brakes are locked, they are not depending on compressed air to hold them in a set application.  It just needs an air set to perform the locking procedure. 

The conventional handbrakes can be retained because they can be set without coupling air and charging the brake system in circumstances where this would be more work than just setting a handbrake.     

But as I mentioned earlier, this is for a highly specialized, dedicated oil unit train consisting of non-interchangeable equipment.  The point is to satisfy the public and regulatory demand for oil train safety.  Overall, this specialized train will have the following features:

1)      More crashworthy tank cars.

2)      ECP brakes.

3)      Single control parking brake.

4)      Zero-slack couplers without draft gear. 

[blue streak 1]

Although not a final solution there is a quick partial fix. Split rail derails with a suitable berm beyond the derail any location where trains  ( not just oil ) are parked. ?  Note on past trip UP was already installing such at haz mat locations even on uphill grades . 

 

 

[CN6218]

  I glad to see someone in the Energy source of the future Industry so interested in trains.  So my question to you:  Are you CANDU or PWR;  enriched U-235 or just ground U-238.

  And when will decentralized LFTRs become commonplace, and which nation will build the first one?

   We (the world) are a petroleum economy.  We cannot do without those polymer carbon chains.  All our tires, petrochemicals, cosmetics, MEDICINES, have a start with crude oil/natural gas. Many of the black tank cars you see on the railroads are carrying the sludge at the bottom of the distillation towers from our Oil Refineries.  This thick black gold is so important to the Cosmetics, Petrochemical, and Pharmaceutical Industries, that they simply call it their "Feedstock"   But no new oil in large quantities has been discovered, and what we have found is getting harder and harder to find and extract.  As costs increase and the price of Transportation fuels  escalates, alternative sources of energy will need to be brought online.

   Nuclear in a decentralized, extremely safe system, with no 20,000 year half life of the waste products of neutron bombardment and atom splitting, will be front and centre. 

  The LFTR (Liquid Flouride Thorium Reactor) is the answer. 

   Coal may be used specifically for making synthetic liquid fuels; thus the need for a Nuclear system to provide our electricity.

[Euclid]

efftenxrfe

I stipulate that hand brakes set on  locomotive units  and a couple of cars held the train, (here's the catch) in combination with the engine's independent. (only the locomotive's brakes) securerment existed

The independent brake was supplied straight from the air pump. If the pump was shut down by a zealous firefighter,  those brakes would leak off.

Your scenario may be correct.  If anybody knows what actually happened to cause the air brake release, the details have not been made public.  What is known by the simple fact that the train rolled away is that there were insufficient handbrakes to hold it.  The Canadian securement rule calls for enough hand brakes set to prevent the train from rolling with air brakes fully released. 

I have seen news reports commenting that the engineer was highly experienced and competent.  So there is no obvious indication of why he would have substituted air brakes for handbrakes in the achievement of securement.  Certainly that decision saved time.

Regarding your characterization of a “zealous” fireman shutting down the engine:  It is a red herring to blame the firemen for shutting down the one running engine, even if the resulting loss of its compressor caused the loss of air brakes.  The fire department had been trained by the MM&A Railroad that the first thing they are to do when encountering a locomotive fire it to shut down the engine(s). 

The firemen did exactly what they were supposed to do, and MM&A had a representative on site with them to make everything known to company management.  MM&A supervisors knew that no engines were running before the train ran away, and they did nothing about it.    

[Euclid]

Any runaway is bad, but location also matters.  I cannot imagine myself feeling comfortable leaving a full train of flammable oil perched on a six-mile hill above a town bisected by the railroad on a speed-restricted curve.  For me, this would have been a major red flag, and I would have insisted on the utmost attention to establishing an infallible securement policy; and making sure it was always properly executed. 

[Will Davis]

Well, I can tell you one certain parallel between the nuclear accidents, and this rail accident, right now, and that's this:

A heated, and likely very productive, debate among those involved in the field as to what went wrong, right down to the nuts and bolts and second by second actions of persons involved.

Now, I only say "likely" productive because it appears that the discussion is occurring without all the facts being known.  That's right - if every single event, the condition of all the brakes on all the cars, etc. were recorded there'd be little debate as to what actually happened.  This exactly parallels the events (early on) at Three Mile Island, and even now concerning Fukushima Daiichi.  Work continues to develop a complete timeline, and only with dismantling of the plants will we finally have the answers as to what exactly happened and when.

This will apparently never be possible with the Lac-Megantic rail accident, so that defaulting to the two normally publicly discussed "fixes" is where the public debate will go.  That means the public says, in order:

•Who did what wrong?  Why did they do it wrong?  Did they know they were doing something wrong?

•Why didn't the equipment prevent such an accident?  Isn't it designed safely?

The first point can go from moment to moment actions on the part of the crew, to operating rules on the railroad, to industry-wide practices and inspections.  It branches to regulatory oversight as well.

The second goes not just to the cars (the tank section) but to the entire railroad train as a whole in the public eye, who see it as the entity whose runaway launched the accident.  Note:  For a long while, the public saw the earthquake as the entity which launched the Fukushima accident.  It was not; it was the tsunami that initiated all of the events that caused the accident.  Finding and identifying the actual triggering event is key in re-establishing public trust.  It's pretty clear the railroaders here are trying very hard to figure out just what exactly happened to start this specific event, and then apply that to railroading everywhere.

(Aside:  For those who have a more than passing familiarity with nuclear issues, the second of my points above has moved up the tree to include the overall safety / viability of every Mk I containment building used on boiling water reactors, anywhere in the world - whether this discussion is legitimate or not, I leave for a future time.  I have my opinions.)

When the industry loses control of the above debate with the public, it can and will default to an overreaching status such as "do we need nuclear power at all" or else, here, "do we need to ship oil by rail at all?" 

Rail has the added DISadvantage, if it can be believed that rail could have a safety perception disadvantage over nuclear, of actually being located right in and around populated areas.  You don't have exclusion zones around plants like we do.  This brings the risk right into people's laps, so that they're more, rather than less, likely to personally and emotionally adopt a "not in my back yard" type of mindset that would lead to "well, then no oil by rail at all" as an end result.  People don't like percentages of risk when it's their kids on a swingset 500 yards from a rail line.  They only want to hear "never."  This mindset would continue even in the face of skyrocketing gasoline prices, etc. should all oil shipment by rail cease, until some breaking point were reached wherein the safety risk would be topped by the need to travel for work or food.

And that's where risk perception comes in.  We all know, at least vaguely, that something like 30,000 people are killed in auto accidents every year in the USA, but we will still jump in the car to run to the store for a case of soda if we're out, then come home, then later run back out to get a movie at the RedBox, then come back home, etc.  We marginalize the risk based upon our perceived notion of how often that happens when compared with the general, normal day we usually have.  It's the "yeah, but I'm careful, that won't happen to me" sort of thing.  This is much easier when we have the choice - we can say, "well if I was that worried I wouldn't go out - heck, I don't drive when it's icy out."  This is impossible when the rail line nearby ships oil cars at times and proximities we certainly have no control over.  So then "if I can't control it, I'll stop it" becomes the mindset to mitigate risk.

Anyway, I hope that I haven't derailed (yuk, yuk) the discussion here, but I continue to notice the parallels and I certainly hope that some of what I've written makes some sense to folks who both work in railroading and have to deal with the public.  This is all coming from our experience, and if you're in railroad PR I'd certainly like to read your perceptions and reactions, and interactions with the public.

-Will Davis

[narig01]

Some kind of off the wall thoughts.

What about a chain to run from the car around the rail to literally tie a car down. Yes I know chains can snap.
As I said this morning what about chocking wheels. Yes I know tiring down the brakes is the preferred way. And yes I know hand brakes are important.

Thx IGN

[tree68]

I've long since come to the conclusion that the Lac Megantic train ran away because the engineer was ultimately depending on the independent to hold the train.  Once the main res pressure dropped to zero, well over half of the axles on the locomotives (those not held by handbrakes) lost their brakes.

Combined with the insufficient handbrakes and the possibilities mentioned here for any service application of the entire train going away, there reached a point where there weren't enough brakes applied to hold the train.  

Some sort of whole-train locking capability, perhaps to hold a full service application on the cars, probably would have prevented the incident, as long as it did not require positive air pressure to maintain that lock.

[zugmann]

Euclid

Oh I see.  I thought you thought I was leaving out the couplers.  Maybe the handbrakes could be retained for that setout, but securement could just as well be accomplished by use of the single control, pneumatically powered brake lock to secure the car with air brakes set fully and mechanically locked in the set condition, just like securing a whole train.

Yeah, couplers would help that, too. 

Again - don't handbrakes set brakes mechanically?  I'm still lost with your definitions and nuances.

[Euclid]

zugmann

Euclid

Then go ahead and set it out.  What's the problem?

You took away the handbrakes.  How am I supposed to tie it down?

Oh I see.  I thought you thought I was leaving out the couplers.  Maybe the handbrakes could be retained for that setout, but securement could just as well be accomplished by use of the single control, pneumatically powered brake lock to secure the car with air brakes set fully and mechanically locked in the set condition, just like securing a whole train.   

[zugmann]

Euclid

Then go ahead and set it out.  What's the problem?

You took away the handbrakes.  How am I supposed to tie it down?

[efftenxrfe]

May I go back to the tragedy?

A train was left stationary, sufficiently secured....to prevent movement then.... and later an hour or so, it moved downgrade, derailed, blew up, "Oh, the tragedy of it!" Lakehurst , NJ.

The securement failed, and a lot of words here  have tried to explain it.

Air brakes....I used 'em" for 42 yrs and taught 'em" at the Engine Service Training Center, SPT's.

Distilling... brake cylinder power is distributed by a device that gets commands to  decrease or increase  of pressure in a control pipe which diverts pressure from a storage vessel into the cylinder which controls the  brake piston, rigging and brake shoes, this on each car and locomotive
The controlling pressure pipe is satisfied....until leakage changes the state of the system..

I stipulate that hand brakes set on  locomotive units  and a couple of cars held the train, (here's the catch) in combination with the engine's independent. (only the locomotive's brakes) securerment existed

The independent brake was supplied straight from the air pump. If the pump was shut down by a zealous firefighter,  those brakes would leak off.

Got a problem with a run-away caused catastrophe?

Were the train brakes set when the engr. got in the taxicab to go to get rest?

.

[Euclid]

zugmann

What if I need to set out a shop with air brake issues?

Then go ahead and set it out.  What's the problem?

[Randy Stahl]

Yes, I understand that but in these scenario's with depleted air and run away trains with odd tapers and gradients , an over reduction (you would think) would get the control portions moving. Agreed that with a fully charged train with a normal gradient an over-reduction is just a dangerous waste.

[BigJim]

Randy Stahl

You would think that the brakes would apply with a over reduction beyond full service but that is not always the case. It depends on the rate of reduction.

That cannot happen because the aux. res. and brake cyl. have equalized. The aux.has applied all the air to the brake cyl. that it can supply. That is why it is called a full service application. Any further reduction is just wasting air from the aux. res.
The only other way to apply more braking effort is to have enough air to initiate an emergency application.

[jeffhergert]

Randy Stahl

Here's something else I learned nearly a year ago. When the rate of the reduction of the brake pipe is very low , lets say a turbine operated EOT and normal train leakage the car brake may not apply. Lets give it 5 hours to leak to zero.

As I now see it there are THREE rates for brake reductions: Leakage rate (on a train without an air supply).

Service rate and emergency rate. As I said with a train off air or on a cut of cars with bottled air the leakage rate may not be enough to initiate a brake application.

 

When a locomotive on a train pumping air shuts down or dies for any reason the air will leak off. Lets say that you have a leak on the train that is slight, perhaps 30CFM. Eventually the brake pipe will leak down and the maintaining feature will keep the brake pipe charged until the brake pipe  equalizes with the main reservoir. (90 psi brake pipe-90 psi main res, point of equalization). If the leakage continues the next thing to equalize are the locomotive brake cylinders (72 psi brake pipe-72 psi main res-72 psi brake cyl) If the leakage continues all three systems will leak at the same rate until there is nothing left in anything.

Once the brake pipe is exhausted there is no way to initiate any kind of brake application, certainly not even a penalty or emergency. You can't go lower than zero. 

 

You would think that the brakes would apply with a over reduction beyond full service but that is not always the case. It depends on the rate of reduction.

 

I was very surprised when I did the experiment with 5 locomotives and 80 cars that the turbine operated EOT didn't cause enough leakage to set the train.

I've had a portion of a train, say about 20 or 30 cars, can't remember the exact number, where the air turbine EOT set up the brakes after an anglecock partially turned while moving.  On the other hand, I too have had about an 80 car portion where the brakes didn't set up because of the air-EOT after the train line became blocked.  Amazing to watch the EOT drop by about 1 lb every few minutes while the rest of the train is in full service.  That kind of situation is why the requirement for EOT's on most trains to have the capability for the engineer to place the train in emergency through the EOT.          

[Euclid]

dehusman

Euclid

You mention a case where brakes in emergency bled off in less than one minute.  First, I am greatly surprised that it could leak off that fast. 

So were we.

You must have heard compressed air leaking loudly in a major flow of leakage in order for the cylinders and reservoir to lose their pressure in one minute. 

Not really if it was from multiple points and there really wasn't a huge volume of compressed air.

I also do not understand why you are making a point about an emergency application leaking off, together with a point about the trainline leaking off.  With brakes left in emergency, the trainline is 100% exhausted, so there is nothing to leak off. 

Sure there is.  Go read how air brakes work.  When the brakes are applied (regardless of the type of application) air is vented into the cylinders, pressurizing them and pushing the piston out, which causes the brake shoes to be pushed against the wheels through a mechanical linkage.   Did you catch where the air pressure is?  Its in the cylinders.  If there is no pressure in the reservoirs because it was vented into the cylinders and there is no pressure in the train line because the emergency application vents to atmosphere, the only place there is pressure is in the cylinders, the things keeping the brakes against the wheels.  When the air leaks out of the cylinders (either back through the brake valve, through the seals on the brake rod or the brake piston), the cylinder loses pressure and brakes release.

Yes, I fully understand that and have no need to go read about it.  And I understand that air leaks off.  I also think it is important to distinguish whether you are talking about air leaking of from the trainline or air leaking off from the cylinders and reservoirs.  You seem to be going back and forth with explanations involving both types of leakage almost as though the results are the same. 

For instance, you started out by saying:

“If the engines were shut down and the train line bled off then there was no air pressure in the system to apply the brakes.”

You are talking about leakage from the trainline leaking off.  You say that the loss of that air would leave no air in the system to apply the brakes.  I disagree.  The loss of air in the trainline causes the brake valve of each car to divert its air to the cylinder, thus applying the brakes.  It does not leave the system with “no air pressure to apply the brakes,” as you say it does.

But even after all this reasoning where you are telling me that the leak off of the trainline leaves no air in the system, you turn right around and lecture me about how the system still has air part of it after the trainline leaks off.  Frankly, it seems like you are going out of your way to create points of disagreement for their own sake where there is nothing to disagree about.

For instance, I said:  

“I also do not understand why you are making a point about an emergency application leaking off, together with a point about the trainline leaking off. With brakes left in emergency, the trainline is 100% exhausted, so there is nothing to leak off.”

When I said “there is nothing to leak off,” I meant leak off from the trainline.  After all, I was responding to your point that dealt exclusively with leakage from the trainline in your quote above in blue.

So when I speak of nothing left to leak off from the trainline after an emergency application (which is true) you turn right around and bring up the air left in the reservoirs and cylinders that hold the brakes on as if this somehow refutes something I said. 

You seem to be disagreeing with me, but I simply cannot pin down the point of disagreement.  I believe this began when I said this in regard to my earlier comment about not knowing if ECP brakes would have prevented the MM&A runaway:

“I do not conclude that because Locomotives were shut down, ECP or not, same thing would have happened. You may be right about that, but ECP brakes are charged and controlled differently.”

I stick by that.  I am simply saying I don’t know, when I said I do not conclude…  I could not reach a conclusion until I knew exactly what caused the MM&A train brakes to release.  You seem to be concluding that ECP brakes would not have made a difference.  Yet if there was a trainline pressure wave that released the brakes, then surely ECP brakes would have prevented the release because they are not controlled by trainline pressure changes. 

[jeffhergert]

Jerry Pier

A very important requirement, not noted is that an unattended triain should be placed in "Emergency" not full service. The Lake Megantic train would have sat there fro a week or more in that state without any risk of a run-away. it takes a little longer to recharge the train but that is minor factor  for the removal of risk. )I wrote on this at the time of the crash but it bears repeating.)

Placing the train in emergency when unattended is not a US requirement. Yet.

When securing a key train, our additional requirements are for a more detailed job briefing with the dispatcher and the engineer taking the reverser out of the cab with him if we can't lock the cab doors on the lead engine.  Trailing units don't need their doors locked or the cab searched for reversers that may be in the cab.

The way our job briefing check list is printed out (first part for securement of any train, second part with additional key train requirements including specific items and verbiage for the job briefing) and reads, many engineers are taking the reverser any time they can't lock the doors on any unattended train. 

Railroads have agreed to limit crude oil trains to 40 mph in high threat urban areas, including a 10 mph buffer zone.  On the Blair Subdivision there is a zone a few miles long that has the 40 mph for such trains.  It's out in the middle of nowhere, but probably touches the 10 mile buffer zone for the Omaha metro area.   

Jeff   

[Randy Stahl]

Here's something else I learned nearly a year ago. When the rate of the reduction of the brake pipe is very low , lets say a turbine operated EOT and normal train leakage the car brake may not apply. Lets give it 5 hours to leak to zero.

As I now see it there are THREE rates for brake reductions: Leakage rate (on a train without an air supply).

Service rate and emergency rate. As I said with a train off air or on a cut of cars with bottled air the leakage rate may not be enough to initiate a brake application.

 

When a locomotive on a train pumping air shuts down or dies for any reason the air will leak off. Lets say that you have a leak on the train that is slight, perhaps 30CFM. Eventually the brake pipe will leak down and the maintaining feature will keep the brake pipe charged until the brake pipe  equalizes with the main reservoir. (90 psi brake pipe-90 psi main res, point of equalization). If the leakage continues the next thing to equalize are the locomotive brake cylinders (72 psi brake pipe-72 psi main res-72 psi brake cyl) If the leakage continues all three systems will leak at the same rate until there is nothing left in anything.

Once the brake pipe is exhausted there is no way to initiate any kind of brake application, certainly not even a penalty or emergency. You can't go lower than zero. 

 

You would think that the brakes would apply with a over reduction beyond full service but that is not always the case. It depends on the rate of reduction.

 

I was very surprised when I did the experiment with 5 locomotives and 80 cars that the turbine operated EOT didn't cause enough leakage to set the train.

[BigJim]

Randy Stahl

BigJim

dehusman

If the engines were shut down and the train line bled off then there was no air pressure in the system to apply the brakes. 

If you believe that, you have absolutely no idea how the brake system works! 

 

He's right Big Jim. When the brake pipe is zero there's no reduction left to initiate an emergency brake application. You can't go lower than zero. Even though the emergency portion of the reservoir is charged there's no way to actuate it.

It's an easy experiment, next time you cut away from a cut of cars don't let them dump. Instead close the angle cock, cut away and open the angle cock slowly until the brake pipe is empty.. now try getting them to go into emergency.

No, he is not Randy.
You are speaking of something entirely different. As the trainline, that was at one time charged, leaked down, the brakes applied until they reached a full service application. Period! 

[BigJim]

dehusman

If the engines die, there is no source of air.  Its bottled.

If the automatic brake is applied, the air is not bottled at all. The pressure maintaining feature would continue to try to maintain the equalizing reservoir pressure setting until it could do so no more.

dehusman

Once the engines died the train was essentially a cut with the air bottled.

No it wasn't. Once the main reservoir leaked down below equalizing reservoir pressure the brakes would continue to further apply until they attained a full service application.  

[Randy Stahl]

BigJim

dehusman

If the engines were shut down and the train line bled off then there was no air pressure in the system to apply the brakes. 

If you believe that, you have absolutely no idea how the brake system works! 

 

He's right Big Jim. When the brake pipe is zero there's no reduction left to initiate an emergency brake application. You can't go lower than zero. Even though the emergency portion of the reservoir is charged there's no way to actuate it.

It's an easy experiment, next time you cut away from a cut of cars don't let them dump. Instead close the angle cock, cut away and open the angle cock slowly until the brake pipe is empty.. now try getting them to go into emergency.