Skip to comments.Insight: How a train ran away and devastated a Canadian town
Posted on 07/09/2013 4:43:49 AM PDT by thackney
...The locomotive caught fire, so firefighters shut off the engine to stop the flames from spreading. That slowly disengaged the air brakes, and the driverless train carrying 72 cars of crude oil rolled downhill into the scenic lakeside town of Lac-Megantic, derailing, exploding and leveling the town center.
At least 13 people were killed and some 37 are still missing, according to Canadian police...
He secured the train at 11:25 p.m. on Friday, setting the air brakes and hand brakes, according to MMA. Burkhardt said the engineer set the brakes on all five locomotives at the front of the train, as well as brakes on a number of cars, in line with company policy. Four of the train's engines were switched off, but the front locomotive was left on to power the airbrakes. The engineer, who Burkhardt declined to name, then retired to a hotel in Lac-Megantic.
Soon after, things started to go wrong. Nantes Fire Chief Patrick Lambert said the fire department got a call about a blaze on one of the locomotives at 11:30 p.m. He said the fire was likely caused by a broken fuel or oil line.
Firefighters reached the scene within seven minutes.
"It was a good sized fire, but it was contained in the motor of the train," Lambert told Reuters. "By 12:12, the fire was completely out."
But as they extinguished the fire, the 12 volunteer firemen also switched off the locomotive, in line with their own protocols, to prevent fuel from circulating into the flames.
One of the many unknowns in the story is precisely what happened next.
Lambert said the fire department contacted the railway's regional office in Farnham, Quebec, and spoke to the dispatcher...
(Excerpt) Read more at reuters.com ...
If an engine needs to remain ON then some train personell MUST remain behind?
The ignorance of the fire department was trumped by the lack of RR personell on hand.
Didn’t chock the wheels?
You beat me to it.
I live across the street from a set of railroad tracks that feed a power plant about a mile north of me. They park their engines there all the time at an idle and the crew jumps into a couple of cars waiting for them and leave, sometimes for an entire weekend.
The tracks are pretty flat but in really doesn’t take much of a grade, certainly enough to not be able to tell by eye, to get them moving I believe.
What a tragedy ... so much human error, even though everyone seems to have followed their own protocol.
Seems to me the RR dispatcher that got the call from the fire dept. should have contacted the engineer and he should have gone out to check the train.
There was another eyewitness report consistent with the story above. Paraphrasing, a group of people were exiting the bar and saw the train barreling into town, several wheels glowing red and smoking. He yelled “run!” realizing the train would never make the curve at its rate of speed.
So the glowing wheels would be consistent with the statement that several manual brakes [sadly and obviously, not enough of them] were applied and those would be the likely source of ignition as the tank cars ruptured. One of the photos of the aftermath showed a tank car pierced with a piece of rail.
I’m still not clear on the timeline, though. What is the actual span of time between the fire service turning off the engine and the actual runaway?
The town is devastated, the engineer is staying at a hotel in town, and what seems to me to be missing is the fate of the engineer, possibly an ironic ending or a really bad wakeup or both.
First thing I thought of, it doesn’t take much if the train is sitting still.
In trucks with air brakes, when the air pressure goes down the brakes come on automatically.
Evidently Trains are different.
Leaving a train with no one around seems a stupid thing to do. Any child or vandal could go on board and release the brakes. I cannot imagine something as expensive as a train left running with no one on board.
Ditto heavy equipment.
Question born of ignorance;
Don't the air brakes lock up when the air pressure in the system falls below a certain point?
Chocks wouldn’t help if it was an SUV train.
Missed your post while composing mine.
Chocks wouldnt help if it was an SUV train.
I’ll bite. What’s an SUV train? This better not be funny.
In the early railroad days runaway trains were common.
George Westinghouse set to work and developed the air brake system. On loss of pressure, the brakes on all cars were released and stopped the train.
Something is not correct about the reporting
Air brakes reduced the need for brakemen that turned the wheels on each car to set the brakes. Even though mostly un needed, railway unions required brakemen decades after they were not needed.
Something doesnt seem right with this explanation. In most air brake systems if there is no air pressure the brakes are ON or applied. Its the air pressure from the compressor that releases the brakes. If the engine is off the air compressor isnt generating air pressure which would mean the brakes are locked ON. In big trucks and even in my motor coach if the engine isnt running to produce air pressure to release the brakes it wont move.
Trains are not different, their brakes go active as the brake line pressure falls.
However, it takes energy to activate those brakes. Each car’s braking system has a reserve tank that holds pressure to activate that car’s brakes. These do eventually leak down if not recharged from the locomotive. If line pressure had not recently been brought up (to unset the brakes at some point), these reserves would have failed here and there, causing the train to lose massive amounts of braking force.
Trains are often left alone. Railroads are private property and they have their own police. Generally, people don’t mess with trains because they don’t want to be arrested and prosecuted. Engines generally are left idling to keep their pure water coolant from freezing (pure water cools better than antifreeze mixture, but there is a freezing risk associated). Recent software for many engines now allow the ECM to cycle the engine on and off to keep the coolant from freezing, saving some fuel.
Same way on trains. Without air the brakes are applied. Not the way the article describes.
This is like the movie Unstoppable.
In air brake systems there are brakes which are spring loaded into the "stop" position, which are activated by loss of air pressure and are used as parking brakes, and brakes which are activated by pressure in order to move into the "stop" position.
It would seem that enough brakes would be of the spring loaded parking type to prevent motion of a train (or truck) with no air pressure present in the braking system, since this is a major safety feature of the systems. But apparently that wasn't the case in this situation, perhaps due to the grade where the train was parked or some other factor.
This accident is another example of how minor problems can compound into a disaster due to human error and ignorance.
Also, here is my theory of what happened:
(1) Sufficient braking force was available when all engines were idling while train was stopped.
(2) An engine caught on fire, and it may not have been the first or last engine in the locomotive line. Fire department put it out and shut down engine.
(3) Braking force was lost on the engine that caught fire, and possibly all the engines after.
(4) Having been sitting for a long time, the car brake reserves were depleted, and loss of a engine and airline problem on that engine caused the brakes to get applied, using the reserve in the car tanks.
(5) Loss of braking on one or more engines allowed the train to begin to roll.
Once rolling, there was no stopping it, since all the brakes necessary were no doubt not going to work whether a engineer was on board or not.
I would guess the chock solution is about the only thing that could have saved the train, other than if the firefighters or railroad had recognized what was about to happen and manually set the car brakes (the wheels on each that can force the car brakes on).
That they went to print with the braking system explanation completely backward is a travesty of Journalism.
In trucks with air brakes, when the air pressure goes down the brakes come on automatically.
Evidently Trains are different.
I went to a talk long ago and far away about train brakes. I also recalled the brakes being actuated when the pressure went away.
It's a little more complicated than that. The brakes are actuated on a reduction in pressure, but the motive force for the application of the brakes comes from an air reservoir aboard each individual rail-car, not from a spring.
A procedure called "fanning the brakes" can deplete all of the reservoirs and cause total brake failure. Don't do that.
I believe it was an attempt at sarcasm based on an SUV being, in the minds of Liberals, an evil and unstoppable piece of machinery with a mind of its own. Not my post ... just explaining what I think he meant. Sometimes people attempt levity to keep themselves from crying.
The reason for the difference between trucks and trains is a result of the amount of braking force required, and limits in practicality.
The size of the springs, the force they exert, and the breaking force required for trucks makes spring actuated air released brakes unworkable.
The size and force of the springs required for a train would make it impossible to assemble the braking system. And certain breaking systems just would not physically work.
An air, or fluid actuated system is the only viable ways to do it.
Since you want the system to apply on loss of air pressure (the line is broken), then you want a reservoir on each unit that is used to power the brakes. And a control line that will engage the brakes if the control pressure drops.
The onboard reservoir will supply breaking force long enough for the operator to correct the line problem, or apply hand breaks.
If the control line is disconnected, and the car is just left there, then the pressure will bleed down and the car will start rolling. It isnt a mater of if, but just how long until it happens.
Yep, you nailed it...
levity to keep from going nutz what with all the other nutty things going on, covered in other threads, seemingly out of control
Sounds logical, the SUV having “a mind of its own” another of the Rush Limbaugh theorem or would that be another insanity of the left.
Something very strange about this incident. Crude oil isn’t all that flammable. Burns like hell once it is started, but needs a real boost to get it going.
I always was under the impression that it takes Air pressure to unlock those brakes. Or on the other hand if the air pressure goes down the brakes will lock up. The only scenario I can imagine is if the locomotive is removed that there is a way for the brake lines to remain sealed and a certain amount of pressure remains and keeps the brakes unlocked until the air finally bleeds off and the brakes lock up. It be interesting to hear an explanation from an engineer familiar with this process.
nice post...now “the rest of the story”
Though not proven at this point, there are background rumours that this incident may have been deliberate eco-sabotage by the anti-oil kooks.
Several groups in the US have already engaged in actions they use to stop the movement of North Dakota oil, and have not been shy about it - they call it “Fearless Summer”. An extremist group called 350 Maine set up a blockade 2 weeks ago - Maine is next door to Quebec.
See my post 9. Ruptured tank cars, a lake of crude comes in contact with red-hot steel wheels, combustion temps reached, sea of fire, intact tank cars start to boil, BLEVE, game over.
Thanks for that post on this thread.
Sadly, this doesn't even make the top 20 for me.
Shesh Some times, my brain is just not in full gear ..
. breaking force required for trains makes spring actuated air released brakes unworkable.
And switch out break for brake
I guess that is why the site has post preview. I guess I should actually use it once in a while.
On a truck yes, but on something as long as a train if the airline failed in the back cars the engineer wouldn't know. It would destroy the wheels obviously, and if he ever went over a wood trestle bridge like that he would probably burn it down behind him.
I was wondering the same thing. Also one article mentions an explosion, but I don't know if the author meant an "explosion" from collision noise or a 2,000 degree over pressure explosion.
Very Interesting. Keep me posted please.
If this was deliberate sabotage they are responsible for multiple murders.
This should give even more importance to the Keystone pipeline.
Perhaps a spring would work better.
No matter the brakes or whatever, a train should never be left alone. IMO.
The cost of one man left with the train is nothing compared to the damage done here.
Westinghouse's 1869 version, the straight or direct air brake, used air hoses to connect the cars. When the engineer turned on the brakes, air pressure turned the brakes on in each car of the train. Of course, if the hoses leaked or disconnected, the train lost braking power.
With air brake 2.0, Westinghouse turned things around. Air pressure kept the brakes off. The engineer reduced pressure to put the brakes on. This built-in safeguard meant a loss of pressure would stop the train automatically. That applied to leakage and to the situation where cars came unhitched: Loose cars would brake to a stop. The system went into use in 1872 on the Pennsylvania Railroad.
FRED lets engineers know about pressure conditions at the end of the train nowadays (it used to be the guy who road in the caboose).
FRED stands for flashing rear end device, and FRED has a radio transmitter and regularly reports conditions on the air line.
I had wondered how the crude got caught on fire.
A heavy train will roll even if a few cars have hand brakes on.
In a word, no.
"An air brake is a conveyance braking system actuated by compressed air. Modern trains rely upon a fail-safe air brake system that is based upon a design patented by George Westinghouse on March 5, 1868. The Westinghouse Air Brake Company (WABCO) was subsequently organized to manufacture and sell Westinghouse's invention. In various forms, it has been nearly universally adopted."
While billed as "fail safe" the Westinghouse air brake system can and does sometimes fail, leaving rheostatic brakes (which don't work w/out engines), manual brakes (which were engaged but on only a few cars), and emergency brakes (which are dependent on air pressure which fell to zero when the engine was shut down). Unlike truck brakes which apply with spring pressure and release when pressure is applied, train air brakes are applied and released by raising and lowering the pressure in a line that runs the length of the train. The individual cars apply their brakes using an air reservoir on each car in response to changes in the "train line" pressure.
Doesn’t sound too fail-safe to me.
I really do believe no train should be left running with no one in it.
All trains have a device on the last car that monitors air pressure and is in radio contact with the head end. It attaches to the air line and is mounted on the knuckle.
It’s called a FRED Unit, which stands for friendly rear-end device. (Sounds kind of gay.)
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