[Newsbot]

Title: Engineer in Lac-M�gantic train disaster suspended
Category: Misc CDN
Posted By: martin14
Date: 2013-07-10 13:49:48
Canadian

[martin14]

Looks like the engineer will get hung out to dry.

[Zipperfish]

Opening gambit by the company. Keep the level of blame as low as possible. I don't think it will work for a disaster of this magnitude. Didn't work for Exxon or BP.

[Lemmy]

Doesn't jive with what's being reported here in Maine. The news here suggests that the blame lies with the fire department who shut off the engine and set the whole business in motion, literally.

[Zipperfish]

Lemmy Lemmy:

Doesn't jive with what's being reported here in Maine. The news here suggests that the blame lies with the fire department who shut off the engine and set the whole business in motion, literally.

I was curious about that. I would have thought the brakes would be designed "fail-close" (that is, if power (air pressure) fails, the brakes are on; it takes power to relieve the brake).

As stated earlier though, it's not uncommon for disasters of this magntiude to be a result of cascading failures.

[martin14]

Zipperfish Zipperfish:

Lemmy Lemmy:

Doesn't jive with what's being reported here in Maine. The news here suggests that the blame lies with the fire department who shut off the engine and set the whole business in motion, literally.

I was curious about that. I would have thought the brakes would be designed "fail-close" (that is, if power (air pressure) fails, the brakes are on; it takes power to relieve the brake).

As stated earlier though, it's not uncommon for disasters of this magntiude to be a result of cascading failures.

I thought the same, that's how trucks are set up.

But trains are different.

[xerxes]

Zipperfish Zipperfish:

Lemmy Lemmy:

Doesn't jive with what's being reported here in Maine. The news here suggests that the blame lies with the fire department who shut off the engine and set the whole business in motion, literally.

I was curious about that. I would have thought the brakes would be designed "fail-close" (that is, if power (air pressure) fails, the brakes are on; it takes power to relieve the brake).

As stated earlier though, it's not uncommon for disasters of this magntiude to be a result of cascading failures.

It usually is. Read up on any kind of air crash and often its a bunch of minor oversights that culminate in a disaster.

[peck420]

Zipperfish Zipperfish:

I was curious about that. I would have thought the brakes would be designed "fail-close" (that is, if power (air pressure) fails, the brakes are on; it takes power to relieve the brake).

They are supposed to fail close. If that train had a standard break setup, it would have had to sit for days before enough air seeped from the reservoir tanks for the brakes to disengage.

None of that, though, explains why the manual brake wasn't engaged?

[BartSimpson]

xerxes xerxes:

Read up on any kind of air crash and often its a bunch of minor oversights that culminate in a disaster.

I've noticed that relationships tend to work the same way.

[Unsound]

Not surprising the engineer is the first to suffer consequences here. Of all the principals involved he'll have the least amount of money for lawyers.

That said he shouldn't be working right now anyways. An incident like this will leave scars, and whether it's his fault or not he shouldn't be trusted with control of that kind of machinery until he's had a chance to recover mentally and emotionally.

As Zip said, I expect that this will turn out to be a result of several things going wrong at the same time. Bad policy followed by poor execution of said policy sounds about right.

[Xort]

A train will have brakes on the engine much like your personal vehicle which are mostly used for stopping smaller loads of cars because:

The main stopping system are air-brakes on every car. When the line pressure drops the brakes are applied, to release the brakes you must raise the line pressure and wait for all the brakes to release. This takes a while so most short trains doing local deliveries or yard work tend to use the engines' mechanical brakes more than the air brakes.

On top of that, every car has a hand brake that will gab one wheel set / axle on one of the trucks. Each engine also has hand brake(s) that can be applied. (some engines have more than one)

You can stop the train on air brakes which will apply every air brake on every car (other than those which are bypassed, which can not be a hazardous material car, their air brakes must work) and then leave the train for up to 3 hrs (IIRC) on the air brakes (by regulation, in reality you can leave the train for about 3 weeks and it's still going to have all the brakes on hard). You can also apply a set number of hand brakes which is normally 10% + 1 for a flat grade. Although local regulations can set a number higher than that. IE in windy places it's often much higher.

From what I have heard this train had 5 engines, and IIRC every one of those engines must have had a hand brake applied. Then the cars must either have had the air brakes on, or a set number of hand brakes, then train must have done a bump test before the crew could leave.

Or I should say that's the rules for a Class I railroad.

I heard that the engineer applied 7 hand brakes to the engines, the conductor would have had to have applied hand brakes to the cars as well.

It's possible that the air brakes were not applied because they wouldn't cover the full time the train would have been left stopped, so only hand brakes were on.

~

As for the fire, you should have been able to burn all the engines to the ground and the cars still should not have moved. Nothing done to the engines should have made any difference. Either the air brakes should have been on, and/or enough hand brakes should have been applied to keep the train stopped. Engine brakes are not counted as being part of the braking force for a stopped train. (for a class I RR)

That said, anyone can walk up to a stopped train and pull a hand brake release. If you ever see a stopped train somewhere without a crew chances are great that you could release all the brakes and let it roll.

[Proculation]

peck420 peck420:

Zipperfish Zipperfish:

I was curious about that. I would have thought the brakes would be designed "fail-close" (that is, if power (air pressure) fails, the brakes are on; it takes power to relieve the brake).

They are supposed to fail close. If that train had a standard break setup, it would have had to sit for days before enough air seeped from the reservoir tanks for the brakes to disengage.

None of that, though, explains why the manual brake wasn't engaged?

The president of the MMA said that the engineer told them he applied 11 hand brakes before going to the hotel. But, he concludes that that was not the case since the train would not have ran away. That's his explanation for the suspension.

But there are other rumours. Since the fire department stopped the engine, the air-brakes were supposed to be activated, the "fail close", since the pressure was off. I've read that another employee of MMA who was there with the firemen may have restarted the engine after the fire was extinguished thus maybe releasing the air brakes.

The hand brakes question is still not answered tho.

[Public_Domain]

[DrCaleb]

martin14 martin14:

Zipperfish Zipperfish:

Lemmy Lemmy:

Doesn't jive with what's being reported here in Maine. The news here suggests that the blame lies with the fire department who shut off the engine and set the whole business in motion, literally.

I was curious about that. I would have thought the brakes would be designed "fail-close" (that is, if power (air pressure) fails, the brakes are on; it takes power to relieve the brake).

As stated earlier though, it's not uncommon for disasters of this magntiude to be a result of cascading failures.

I thought the same, that's how trucks are set up.

But trains are different.

Yea, in reading about the 3 way valving they use, it seems they use a differential in air pressure to open or close the brakes. If there is a leak in the lines, and the locomotive isn't keeping the lines at pressure, they will leak and slowly open. Opposite of the air brake systems on heavy trucks.

[DrCaleb]

martin14 martin14:

Zipperfish Zipperfish:

Lemmy Lemmy:

Doesn't jive with what's being reported here in Maine. The news here suggests that the blame lies with the fire department who shut off the engine and set the whole business in motion, literally.

I was curious about that. I would have thought the brakes would be designed "fail-close" (that is, if power (air pressure) fails, the brakes are on; it takes power to relieve the brake).

As stated earlier though, it's not uncommon for disasters of this magntiude to be a result of cascading failures.

I thought the same, that's how trucks are set up.

But trains are different.

Yea, in reading about the 3 way valving they use, it seems they use a differential in air pressure to open or close the brakes. If there is a leak in the lines, and the locomotive isn't keeping the lines at pressure, they will leak and slowly open. Opposite of the air brake systems on heavy trucks.