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Canadian trail derails, starts inferno...
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kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
I do hope this is not too close to any of our Canadian Setizens... And thoughts going out to those it HAS affected. Train carrying flammable liquid derails, bursts into flames in Canada. "Freedom is just Chaos, with better lighting." Alan Dean Foster |
celttooth Send message Joined: 21 Nov 99 Posts: 26503 Credit: 28,583,098 RAC: 0 |
Oh my, we will be watching this one. |
Carlos Send message Joined: 9 Jun 99 Posts: 29718 Credit: 57,275,487 RAC: 157 |
Glad your safe Ian. This makes a good case for pipelines. They tend not to crash. |
kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
Glad your safe Ian. I was thinking the same thing, but apparently the environmentalists prefer a good train crash and burn once in a while. "Freedom is just Chaos, with better lighting." Alan Dean Foster |
James Sotherden Send message Joined: 16 May 99 Posts: 10436 Credit: 110,373,059 RAC: 54 |
And it looks like it was in a high density commercial and residential area to. [/quote] Old James |
kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
Sadly, they are currently reporting at least one death and several more unaccounted for in the aftermath. "Freedom is just Chaos, with better lighting." Alan Dean Foster |
Donald L. Johnson Send message Joined: 5 Aug 02 Posts: 8240 Credit: 14,654,533 RAC: 20 |
Sadly, they are currently reporting at least one death and several more unaccounted for in the aftermath. And a large chunck of the downtown area destroyed.... Donald Infernal Optimist / Submariner, retired |
Wiggo Send message Joined: 24 Jan 00 Posts: 34744 Credit: 261,360,520 RAC: 489 |
Yes, that doesn't look good at all. My condolences to all those effected. Cheers. |
John Clark Send message Joined: 29 Sep 99 Posts: 16515 Credit: 4,418,829 RAC: 0 |
Another horror ... my condolences It's good to be back amongst friends and colleagues |
kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
Latest news on CNN... At least 3 now confirmed dead, and they are fearing more. And, as it turns out, the train was UNMANNED. It had been parked for the night 7 miles away from Lac-Megantic, broke loose, and rolled runaway before it derailed. From CNN..Death toll expected to rise in Canadian town devastated by runaway train. "Freedom is just Chaos, with better lighting." Alan Dean Foster |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
And, as it turns out, the train was UNMANNED. That's just carelessness on the part of the last crew, unless it turns out to be defective brakes. The advantage of train over pipeline is flexibility of destinations. Once you build a pipeline from an oil field to a refinery, you're pretty much locked into sending all your oil from that field to that refinery. A train can go to many different places, and even have its destination changed en route. Also, pipelines take time to build, even after they get approved. David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
kittyman Send message Joined: 9 Jul 00 Posts: 51468 Credit: 1,018,363,574 RAC: 1,004 |
And, as it turns out, the train was UNMANNED. The BBC article that Chris posted a link to indicates that the 73 tanker cars somehow came uncoupled from the engines, and they then rolled downhill until they derailed. I am not a train expert. Air brakes on a truck self-apply in the absence of air pressure and can only be released by pumping the system up. So in the case of a system failure, the brakes are on. Do rail cars not work that way as well? "Freedom is just Chaos, with better lighting." Alan Dean Foster |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
And, as it turns out, the train was UNMANNED. It's not that simple, no. There are many circumstances where a train car needs to move without any air in its brake system. I don't quite understand it myself, but the basic principle is that each train car has an air reservoir. When the engineer releases the brakes, the brake pipe running the length of the train (via hoses between cars, of course) is charged up. The cars' reservoirs fill up, and a valve on the car admits pressure to one side of the brake cylinder to release the brakes. When the engineer applies the brakes, he reduces the pressure in the pipe and the valve on the car uses air from the reservoir to apply the brakes. When the engineer releases, the valve senses the increase in the pipe pressure (hastened by a main reservoir on the locomotive) and uses air from the reservoir to release the brakes. At the same time, it also directs air from the pipe into the reservoir to refill it. The pressure in the pipe and in the cars' reservoirs can bleed off over time if there is no locomotive connected to maintain it, or manually when necessary. I don't quite get it, but apparently it can even bleed off if there is a locomotive but no one keeping an eye on it. Therefore, it is standard practice, at least in my observation, for crews that are parking a train and leaving it for a while to set the hand brakes on at least a couple of cars. On a grade, they would set more of them and maybe even chock a few wheels. For the train to have separated from the locomotives, it sounds to me like someone must have been messing with it. Stopped trains don't uncouple themselves. This same someone may have also released the hand brakes, or the crew didn't set them, or didn't set enough of them. I now withdraw my earlier accusation of carelessness and will wait for the investigation to figure out what happened. This technology is well over 100 years old. It could be done better, but not without converting the entire continental fleet of hundreds of thousands of cars and locomotives to a new system all at once, which would cost billions of dollars, which would filter down to consumers as higher prices for products, energy, etc. For certain dedicated unit trains, there is a new system called ECP (electronically controlled pneumatic) brakes that has a wire running through the cars. The air pipe is always at full pressure and set/release commands are sent through the wire (which has the added benefit that all cars set or release at once instead of the pressure change having to propagate the length of the train). But cars equipped with ECP brakes can't be mixed with regular cars in the same train. Also, locomotives have to have special equipment installed to operate ECP brakes. David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
The pressure in the pipe and in the cars' reservoirs can bleed off over time if there is no locomotive connected to maintain it, or manually when necessary. I don't quite get it, but apparently it can even bleed off if there is a locomotive but no one keeping an eye on it. Therefore, it is standard practice, at least in my observation, for crews that are parking a train and leaving it for a while to set the hand brakes on at least a couple of cars. On a grade, they would set more of them and maybe even chock a few wheels. Addendum: my (non-professional) experience is with American railroads. I doubt the practices are much different in Canada, but they could be slightly. David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
James Sotherden Send message Joined: 16 May 99 Posts: 10436 Credit: 110,373,059 RAC: 54 |
Canadian and American train cars are routinly on each others tracks. So I would think they operate mechanicaly the same. Sounds like vandalism to me offhand. [/quote] Old James |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
Canadian and American train cars are routinly on each others tracks. So I would think they operate mechanicaly the same. Sounds like vandalism to me offhand. Mechanically yes (federal regulations in both countries, and Mexico, require it), but operating practices could have minor variations. David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
Canadian and American train cars are routinly on each others tracks. So I would think they operate mechanicaly the same. Sounds like vandalism to me offhand. And beyond the legalities, the Association of American Railroads (AAR) has standards that cars must meet to be interchanged from one railroad to another. In rare circumstances, such as an antique car moving to a museum, the railroads involved in a movement can agree to waive these rules, as long as their own inspectors deem it to be safe (and they might put restrictions on the movement). David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
cov_route Send message Joined: 13 Sep 12 Posts: 342 Credit: 10,270,618 RAC: 0 |
There is a picture that might be of the train before the accident. It is not for sure yet. I appears to be on fire. https://twitter.com/pascalrobidas/status/353549895988305920/photo/1 The caption reads "Image sent to RadioCanada of the train about 10 km from Lac Megantic (near Nantes) before it exploded". Lac Megantic is about 250km from me. 150 miles. |
Bill Walker Send message Joined: 4 Sep 99 Posts: 3868 Credit: 2,697,267 RAC: 0 |
I think that picture shows the fire well behind the loco in the foreground. From pictures on Canadian TV, there were only tank cars in the fire and explosion. There are a lot of questions to be answered. First one is why did the cars move. As earlier posts said, Canadian cars are mechanically identical to US ones, and operating rules are similar. It appears from initial interviews with the train crew that a block of cars somehow uncoupled from a stopped, manned train. Vandalism is one possibility, but not the only one. Another very big question is how do you get crude oil to explode? It is usually fairly hard to ignite, and then it usually burns rather than explodes. The cars derailed in a commercial district, maybe a runaway car struck a gas meter or an electrical device. There were still fires burning Sunday PM local time, so it may be a day or two before anybody can answer that one. |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
There is a picture that might be of the train before the accident. It is not for sure yet. I appears to be on fire. It looks to me like the headlight is dim and the ditch lights are off. This indicates to me that there was no crew in the cab (or possibly that they were approaching an oncoming train on an adjacent track). David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
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