We can't change rule brakers so we'll punish people who follow rules

This week's post is based on some thoughts I've had after reading the TSB report on the Quebec rail disaster last year... I don't like to touch politics but the investigations and aftermaths have been very political events...

It's been over a year since the rail disaster in Quebec. The TSB investigation report is finally out and is publicly available on their website (if you do care to read, Google it, it's not linked here).

I didn't read it in great detail or try to analyze every little section. My intelligent reading stopped at the early part in the report where it stated that the locomotive engineman performed a handbrake effectiveness test with locomotive independent brakes applied. The rest of the report became a formality from there.
A simple Google search will yield some quite detailed information on freight train brake systems in North America. Briefly speaking, for a conventional freight train, there are 3 sets of brakes. Two of which are pneumatic, 1 mechanical.

The pneumatic brake system that is responsible for brakes on the entire train is referred to as the Automatic Brake, it sets up and releases automatically according to the pressure in the brake pipe that runs through the entire length of the train. The brake pipe is also the air supply for two reservoirs where the brake cylinders take air from. During a service brake application,brake pipe pressure decreases at a controlled rate, automatic brakes come on, brake pipe pressure decreases some more, automatic brakes come on a little tighter. The most common brake pipe pressure at a released state is 90 psi, this number can be adjusted for different railroads' needs. In this case, all the air comes from what's called the Auxiliary Reservoir on the freight car. Braking force reaches a maximum or equilibrium as the pressure in the Auxiliary Reservoir and the brake cylinder equalize (hook up a filled balloon with an empty one, they'll equalize to the same size with the same pressure within). When brake pipe pressure drops dramatically, an emergency brake application initiates and the Emergency Reservoir comes into play and adds more air in the brake system, take a third, bigger balloon, and add to the 2 that have equalized, the equalized balloons become a little bigger until the reach the same size as the slightly deflated third balloon. Due to mechanical limits in the control valve, a complicated mechanical valve that controls the freight car brake system, emergency application can't be initiated when brake pipe pressure is at around or below 40 psi. As I mentioned, brake pipe pressure rises, brakes release. For North American freight train brake systems, this release comes all in one go. You can't release the brakes bit by bit as opposed to them being applied. This is also due to certain mechanical limits in the one brake pipe system that the railroads have adopted for more a long, long time. So far, this system has proven to be reliable and cost effective. Remember, North American railroads are private enterprises. There is money to be made and there are shareholders to be pleased.

Existing operating rules in Canada, called the Canadian Rail Operating Rules, requires trains to be secured without air brakes. The Rules require that a sufficient number of hand brakes are applied and their effectiveness tested by means of releasing all air brakes and cause or allow the slack to adjust.

I don't think I need to say much more at this point, with the fact that the MMA engineman had performed a hand brake effectiveness test with independent brakes on the locomotives fully applied.

However as we all know. Government these days aren't elected based on policies and abilities to lead the country into a better future. Voters, like shareholders, appreciate showmanship, unsustainable slashing of upfront and visible costs, and incoherent, illogical arguments catered to the lowest common denominator.

Naturally, instead of looking for ways to improve enforcement and compliance of current rules, should they be followed Lac Megantic would have not happened, the government must, in good spirit and ultimate wisdom, introduce crowd pleasing regulations that put more restraint and complexity on railroad operations. As if somehow this entices ones who are too lazy to follow rules properly embrace them now.


M-NL said…
What I don't understand about train brakes is that they are not fail safe under all conditions. No air also means no brakes. Ever since Westinghouse created the basics of the current system this hasn't changed.

Road vehicle air brakes are fail safe: no air means that the parking brakes are on. It means that trains with disconnected air pipes are always on the parking brakes. Also you can't run out of air while descending a grade. Even though that's inconvienient for shunting, it would have prevented a lot of accidents.

Adding a similar system to trains doesn't even break compatability: Full braking is realised at around 70% of full brake pipe pressure. You could create a spring release that releases the parking brakes when the pipe pressure exceeds something like 25% of full pressure.

But like you mentioned: both railroads and politics are only interested in economics. Only really major accident will change their minds. Lac Megantic incredibly wasn't really major enough.
Ken Wadden said…
Actually a sufficient number of 'parking' or mechanical- manual hand brakes would secure a train from moving anywhere. Without the air brakes charged or applied. So long as the tonnage and terrain where it's to be left are taken into account.

Apart from the lack of a push-pull test, the hand brakes cranked with the pneumatic system applied ( each car should have air system drained i.e.bled off to ensure hand brake effectiveness )and that seven rather than the required nine were manually secured nothing would have prevented the tragedy under the circumstances.
It would have taken at least triple that number. MMA, Transport Canada and the TSB should have accounted for it.

Yes the automatic / pneumatic brake system on today's freight trains do have their failings. Yet to become an industry standard in North America is an air brake system that has been around since the 30's. Electro-pneumatic brakes. Generally in use on single commodity, heavy haul unit trains outside of Canada.

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