Air Brakes on the Alberta Coal Branch

This story was published a year ago on another blog that I maintain. I'm re-posting it
here today because I received an email from a gentleman who was commenting on the use of "retainers".


It was nearly 20 below on a cloudless November night, We had picked up our train of limestone at the mine and were making about 25 or 30 mph along the undulating track of the Alberta Coal Branch. The fireman leaned forward and told me to lace up my boots and get my parka and mitts on.
"You gotta go back and put up the retainers", he said.

I smiled, and said, "I'll be ready to go when the train stops".

"You don't understand, kid" he said, "Get your gear on now..., and get going.” “The train isn't going to stop".

"It will stop if there's going to be any retainers put on," I said.

I have done some pretty scary things in my career, but going 'over top' from one cross-hopper to another while putting up retainers ranks among the most frightening things I could imagine. There are no handrails up there…just an eight inch wide, frost-covered steel cap on the side walls of the open top cars that were waddling along in the dark, Rocky Mountain Foothills.




The photo above was taken by Ray Matthews has been published In CNLines SIG.

***The smoke was common on trains descending long grades. The brake shoes got so hot they'd turn the wheels blue. Sometimes, we'd have to stop for twenty minutes to let them cool down so the wheels wouldn't fracture and break up.***

I soon realized that perhaps I was just being a 'chicken'. If was really true, as the engine crew insisted that brakemen had been putting on retainers 'on the fly' on The Branch for years and not a single fatality had been reported. Well, none had been reported, but there were a few old Edson railroaders around who were missing some fingers. Slim Amundsen told me once that he had lost his putting out a short flag on the passenger train. He was putting down the torpedoes when the engineer on his train released the brakes, and the slack ran out, taking off three of his fingers!!!

I'd figure it out, I thought as I stepped out of the warm cab into the frozen night. Flipping the switch on my trusty trainman’s lantern, I stabbed the feeble light into the darkness looking for the best way to get myself from the rear platform of the locomotive and onto the ladder on the end of the car. Shaking off the vision of my body laying between the rails in numerous pieces after I had fallen from the top of one of those bouncing, twisting, rocking cars, I leaned out and grabbed at the nearest hand rail.

My hand found a hand rail on the car and held on tightly. Swinging across the void between the engine and the car, I planted my boots on a ladder rung and immediately "gave thanks."

I knew how retaining valves, or “retainers” worked….sort of. Lots of railroaders had mentioned them; told stories about using them on steep grades long before the advent of modern brake systems.




Please note: Retaining valve mounted on the end of the car immediately to the left of the hand brake wheel.
Photo source unknown. BH Collection

They always finished their stories with "But, you know...we don't have to use 'em anymore since they got the new 26L brake valves on the engines". Well, here I was trying to keep my balance on the top of a pile of crushed rock in an old steel open-top hopper that was jolting down the track in the middle of nowhere. Where were those old railroaders with their stories now?

26L brake valves incorporate a 'pressure maintaining' feature which is designed
to hold, or maintain the pressure in the brake pipe and its associated brake valve components on each car in the train.

The braking system of each car is made up of many components such as pipes, fittings, rings, gaskets, pistons, cylinders and much more. At every fitting, there is the potential for air to escape from the system and since train air brakes are kept in the release position when the system is fully pressurized, any loss of air pressure will allow the brakes to be applied. Therefore, system leakage, if not kept under control will cause the brakes to apply and...if there is too much leakage, and the brake control valve in the locomotive cab cannot replace the air at a controlled rate, the train will stop and can not be moved safely.

All right!!! Now I know that the highlighted link below is going be an eye-opener for many of you. The readers of this blog range from the very young to....well, those of us who have gone to seed! Some are railroaders and some used to be railroaders. But you wouldn't be here if you didn't have the "bug". The link below will give all of you an idea what it was like to be an engineer in the days before the advent of 'second generation' diesels. There were many of the older locomotives in service in the era that was my favourite and the time when I earned my engineers certificate. And, yes grandpa, I had to know and understand every component you'll find at that link, and much more! Enjoy.

The predecessor of the 26L brake valve was the 24RL brake valve. Initially, the 24RL did not have a pressure maintaining feature, but I understand that in the few years prior to its demise, a pressure maintaining feature was introduced in the 24RL. Some CN enginemen used a tricky 'engineer magic' thing they called Feed Valve Braking,where they utilized the 24RL brake valve and the supply valve that controlled the amount of air, or total pressure that the brake valve was able to pressurize the train air brake system to. The use of Feed Valve Braking was frowned upon by the railroad and was not allowed by Transport Canada, but it worked.

Retaining valves are just a little piece of equipment. They’re a small metal valve with a smallish diameter pipe coming out of the bottom and running to somewhere in the brake apparatus within the steel framework that supports the end of the car above the trucks that house the big steel wheels that carry the whole thing on the rails. On the side of the valve, is a small handle that pivots and can be set at “exhaust”, “low” or “high” pressure settings.

Its function is to trap a bit of air in the air brake system so that, when the brakes have been applied and then released, a small amount of “brake effort” is retained on that individual cars’ brake system until it's released by returning the valves handle to the "off" position once again. Retainers were used when heavy trains, such as aloaded Rock trains like this one from Cadomin Alberta could be safely brought down long steep grades by maintaining some brake effect on the train all the while recharging the air in the train's brake pipe and reservoirs. The idea is to keep the train speed under control, thus preventing runaways that would result in demerits being handed out to the crew, or worse.

Normally, the train would be stopped a safe distance from the top of the hill prior to descending the grade. At this time, the trainmen would start out from both ends of the train, climbing each ladder in turn, to the brake platform and setting the retainers. Generally, this meant a delay of from twenty minutes to three quarters of an hour depending on the length of train, weather conditions, etc. The same thing would happen at the bottom of the hill after safely descending the grade. The train would be stopped and the trainmen would return to their respective ends of the train, all the while replacing the retainers handles to the normal, or “off” position.




This procedure was what the Uniform Code of Operating Rules called for. This procedure was what any mother would want her son to do under the circumstances. But this was not what this Coal Branch crew did. They “put up” and “took down” retainers “on the fly” no matter what the conditions, the time of day or the season. On the fly!... I have to tell you that I was terrified and was quite sure that I would not survive the night; because I had fallen from the top of a wildly swaying car.

I desperately clung to the frozen steel of those cars with phosphate dust burning my eyes and frost stinging my ears. Fumbling in the dark, and focusing on getting this job done...one car at a time, I eventually came upon the tail end brakeman. He had completed his share of the job and was standing on the drawbars in between the cars, holding onto a grab iron with one hand while he smoked a cigarette with the other. I huddled in silence in the blowing snow and dust, choking on the thick brake smoke and the tail end brakeman hooked one arm over the end of the car and casually smoked a cigarette while we waited for the train to snake its way to the bottom of the hill.

Once there, we parted company, that brakeman and I; he headed off through the thick brake-shoe smoke toward the caboose, removing retainers from each car as he went. And I headed back toward the engine, doing the same.

Not a word was spoken in the cab for the remaining hours and miles back to the yard in Edson.

After yarding the train, I put the engine on the shop track. Gathering my kit from the floor of the cab, I headed across the rail yard toward the office.

The conductor stood silently watching me as I entered the booking-in room at the station. I set my grip down on the bench and stepped gingerly up to the operator's wicket to check the train register and the train lineup for the trip back to Jasper.

Pulling himself up to his full height of six foot three, and leaning a bit in my direction, he said "If you're not goin' to cooperate with me son, you needn't bother takin' a call for the 'Branch' again". “You Jasper boys aren’t welcome here 'cuz you don’t want to do as you’re told”, he said as he turned his head and spit a long black streak of tobacco juice toward the trash can in the corner, narrowly missing my arm when he let fly. Tobacco juice and saliva, resembling a minor oil spill ran in a jagged track over the papers and cold cigarette butts that had been discarded there.

“I won’t be back if I can help it”, I said, coldly.

"That's for damn sure". he said. A blast of icy, winter air brought snow scurrying into the room as if trying to escape the minus 25 degree Edson winter. The door closed behind him.

I felt sure that it would be better to be laid off and taking unemployment benefits than to take a call to join his crew on the Branch again.

Checking my watch, and bemoaning the fact that the town of Edson had rolled up the sidewalks, effectively closing every eatery within walking distance, I sat down on a long, hard bench in the passenger waiting room.

With at least a couple of hours to wait before the first westbound freight might show up to take me back to Jasper and my warm bed, I took a deep breath and closed my eyes.

I thought of my family back home in Ontario.

A Rock On The Track, Or Not!

From 1995 to 2000, I worked as an engineer on CN's Okanagan Division between Kamloops and Kelowna, both in B.C., with headquarters in Vernon.  The majority of the assignments were day jobs that started and ended in Vernon, and the rail traffic that was collected in the Okanagan was hauled to Kamloops by the only night job which left Vernon just past the supper hour.  Arriving in Kamloops after midnight, the same crew would make up their southbound train and leave for Vernon, hopefully arriving there within 12 hours of going on duty in Vernon the evening prior.  As often as not, one of the day jobs would have to climb into a vehicle and head out into the hills to find "the south" and bring it into town.  More on that another time.

This story is about one of the trips I made as the hogger on 455 and 454, Vernon to Kamloops and return.

There was nothing unusual or outstanding about this trip.  A warm night, late in the summer; the weather was good and our train was all made up on the main line with power on and air test completed.

We had our paperwork in hand and climbed aboard the lead locomotive of three SD40-2's that would take us to Kamloops and back home again.  When the SBU on the last car announced that the entire train was moving, I announced on the CPRail radio channel that we were entering CP territory and would be travelling northward from Vernon to Armstrong.  This was a requirement when making a movement on "joint track" where two or more railroads share running rights on each other's tracks.  With fifty or more cars in tow, we made our way slowly over CP's rather rather poorly maintained railroad.  After stopping at Larkin siding to pick up forty cars of forest products that one of the day shift jobs had collected at the mill, we advanced a few more miles to Armstrong where we re-joined CN's Okanagan subdivision.  From Armstrong to Campbell Creek we were the only train on the road.  All we had to contend with were the steep grades, the last one was from Monte Lake, descending 1240 feet to the CPR mainline at Campbell Creek; a distance of sixteen miles.

This hill, at least by CN standards was quite steep at 2% for much of its run and seldom less than 1.5% and was limited to a maximum of 25 miles per hour.   There is a tight horse shoe curve in the middle of it that is restricted to 15 miles per  hour.

There is a bit of mathematics and good ol' seat of your pants running involved in what comes next.  In train air brakes, the braking system is charged up to approximately 90 pounds per square inch.  This keeps the brakes in "released" position until needed.  When I want to apply brakes to the train, I reduce the air pressure in the brake pipe system and the brakes will be applied to the wheels throughout the train.  The degree to which the brakes are applied is dependent upon the amount of air I take out of the system.  For example, a 'minimum' brake application is obtained by reducing the brake pipe pressure by 6 to 8 pounds per square inch.  A minimum brake application really doesn't have much effect on speed reduction; rather, it serves to stabilize the slack that abounds in a long train.  With the slack under control, the engineer can then apply the brakes a little heavier without so much risk of damage to cars and lading.  The use of "power", or throttle during a brake application and/or release can affect the train's handling and stopping distances.

I mentioned "mathematics" in the paragraph above, and I think that it needs to be explained before we go on.
Through an extensive process of trial and error, locomotive engineers have developed operating practices that dictate certain parameters which enable safe handling of trains on grades, and in many other situations.  These operating practices are not dissimilar to the way we drive our cars on the roads and highways.  When you're travelling on a city street at 50 kilometers per hour (30 mph +/-) and the traffic light ahead of you changes from green, to yellow and then to red...you have to begin a process that's not unlike that of an engineer.  Your right foot (in North America) moves from the accelerator pedal to the brake pedal where you apply a small amount of pressure.  This begins to slow the vehicle down and you "read" the rate of decline in speed with a view to stopping at a predetermined spot that hopefully, lies before the red light and not beyond it.  If you find that you've applied too much pressure on the brake pedal and will stop before you wanted to, you can then reduce the amount of pressure on the pedal.  Using the brake and accelerator (throttle) in this fashion, you'll bring the vehicle to a safe stop in exactly the spot you had planned for.

Engineers handle their trains in much the same way as you handle your car, except for a couple of points.  In many cases, the starting point at which the braking process must begin is critical.  But it's not just knowing where the 'tipping point' is; there are other factors that must be taken into account such as the length of the train, the train's weight, the number of loads versus the number of empties, the presence of snow on the ground, the depth of the snow, when was the last time you used the brakes and the number of cars you have on the train that are running with the brakes having been "cut out" due to mechanical problems.  As well, the engineer should have a fully charged brake pipe before beginning the descent to the bottom of the hill.  If you've used the brakes within fifteen to twenty minutes prior to beginning the run down the hill, you will have less braking capacity to call on when  you need it.  Also, if there is snow on the ground, and the snow is either blowing and drifting, or is standing deep above the rail head, it's a pretty good bet that snow has built up between the brake shoes and the wheel treads.  This factor, among all others can present the greatest threat to the crew because, when the brakes are applied the snow gets jammed inside the retarding surfaces and becomes a thin layer of ice!  Now, faced with a very serious dilemma, the engineer slams the brake valve hard over into "the big hole", putting all of the train's brakes into emergency.  This does not reduce or eliminate the ice that has formed between the brake shoes and the wheels, but compresses it further, making it even more dense.  In time, the ice will melt, and the brakes will come on, but by then, it's usually too late.  The train, which until then was under control,  is now a runaway and the crew will either jump off if they feel they can survive the plunge, or will ride it out and hope for the best.

Not to be-labour the point, but in keeping with CN's practice, none of the locomotives in our consist were equipped with dynamic brakes.  We would have to rely on train and engine air brakes to bring us down the hill to a stop, just clear of the CP mainline at Campbell Creek.

Not to worry, I had made a few trips on this run and was getting the hang of it.  The conductors were no longer riding with one hand on the emergency valve in front of their seat, but they didn't allow themselves to fall asleep, either.

With the speedometer holding at  23 mph, the engine passed mile post 28.  This was the time to set the brakes for the run down the hill. I drew seven or eight pounds of air from the 'equalizing reservoir' in the locomotive's brake valve.  The movement of the piston in the equalizing reservoir, in turn allowed air to escape from the brake pipe, causing the brakes to begin to apply in each car in the train.  The sound of rushing air filled the cab as the brake pipe pressure was reduced.  The brake pipe pressure gauge on the control stand dropped accordingly.  Pressing the engine brake handle down, I bailed off the pressure in the locomotives brake cylinders so that there would be no brakes applied on the engine.  I reduced the throttle a bit and watched the speedometer.  At the same time, the load meter on the control panel showed a drop in amperage in the traction motors that are hung on each driving axle and the big diesel engine behind the cab reduced it's rpm's accordingly.

As more of the train followed the engine past the 'tipping point' at the crest of the hill, our speed began to increase slightly.  At 30 mph, I took another couple of pounds of air from the brake pipe and reduced the throttle one more notch.  Out of a total of eight throttle positions, or notches, I had used up two of them.
Working power and air, I got the train settled in at a comfortable 27 miles an hour...just two miles an hour over the speed limit.  Now, less than a mile from the beginning of the 15 mile per hour slow order on the horse shoe curve, I begin to reduce the power, one notch at a time.  I watched the speedometer for the beginning of a drop in speed  that would bring us to somewhere near the 15 mile an hour requirement on the sharp curve.  The speed was dropping, but not enough, so I shut the throttle off and began to add engine brake, five pounds at a time.  Because of the curvature of the track in this area, I didn't want to put too much engine brake on, because it would cause the slack to run in.  The slack, which must be kept under control at all times, had been kept stretched out by using train brakes against locomotive power during our descent.

If the slack ran 'in' too hard, it could cause sufficient thrust against the rails in the curve to force the rails to roll over causing a derailment.  If the slack ran 'out', it could cause the train to break apart.  Fortunately, ten to fifteen pounds on the independent (engine) brake was enough and the train slowed to 15 just as the engine entered the curve.  I carefully released the engine brake and began to add power, carefully stretching the slack and pulling the train through the curve.

Soon, we were back up to 25 miles an hour and drifting toward the bottom of the hill with the throttle in the fourth notch.

In the last few hundred yards of the hill, the grade eases to less than 1%.  In order to stop the train, all I had to do was reduce the throttle to idle and the train would come to a nice stop, with the slack stretched.

There was a busy road crossing about 3/4 of a mile from the CPR mainline crossover switches, and I had to stop the train at the crossing where we were met by a taxi that would take the conductor to the switches.

By the time the train stopped at the bottom of the hill, the conductor had already obtained a CPR clearance and copies of any pertinent train orders and bulletins that might be in effect.  Once the taxi delivered him to the  switches,  he lined all the cross-overs and gave me a big proceed signal with his lantern.  When I released the brakes, the train began to roll ahead.  I held the speed in check, using the engine brake to gather the slack while the fully loaded train pushed from behind.  As the slack was being collected, the train was gaining momentum.  When the speed reached 15 miles per hour, I made 12 pound brake reduction to keep the trains' speed at that speed while we navigated the switches and crossovers from the Okanagan sub across the eastbound main line and onto the westbound  mainline.

After the entire train had cleared the crossovers, I stopped the head-end at a small private crossing, about two miles along on the westbound mainline.  The conductor soon arrived in the taxi, and climbed aboard once again for the run to the city of Kamloops where we will leave CP tracks and re-enter CN tracks for the run out to Kamloops Jct. where the Okanagan sub meets the Ashcroft sub and the Clearwater sub.  Yarding the train in a clear alley, we "change ends" on the locomotive consist.  We'll be taking the same power back to Vernon, so we'll be operating from the opposite end on the return trip.

We back the engine onto the southbound train and cut in the air.  While we're waiting for the Carmen to finish servicing the VIA train that's standing on the main in front of the station, we walk over to the yard office for a cup of coffee and a chat with whoever might be hanging around.

A couple of hours later, we were back on CN track, grinding slowly up the hill from Campbell Creek to Monte Lake.  I don't recall how many cars we were bringing back to Vernon, but the total tonnage was close to the maximum for those three locomotives.  We were down to 6 or 8 miles an hour and I was riding the manual sanders button to keep the wheels from slipping.  One wheel slip could cause the train to come to a very quick stop and we'd have to take our train up the hill in two separate runs.

The conductor and I turned on the cab lights, he to read the Vancouver Sun, and me to try to finish a book I was enjoying.  If all went well, we would be climbing the hill for the better part of two hours.

At one point in the climb, we crept along a steep rock face of basalt.  It was a stable formation, so I wasn't concerned about falling rock, but out of natural caution, I took my eyes from my book and looked at the track ahead.  And there, right on top of the rail in front of me was a rock the size of a mandarin orange.  I mentioned it to the conductor and he took a quick look at it and returned to his newspaper.  Jokingly, I suggested that we stop and remove it from the track.  He smiled and said that I should keep my eye on it because it would probably just hop off the rail to avoid being run over.

Illuminated by the very bright lights on the front of the locomotive, the "rock" that was sitting on the rail began to move!!!    When we were within 20 feet from it, the "rock" turned and looked at us.  It was a small bird and it wasn't making any attempt to leave.  Concerned for its safety, I flipped the ditch lights on and off.  It didn't fly away.  Instead, it shuffled a little closer to the edge of the rail.  Reaching for the air horn handle, I gave a short blast on the whistle.  It seemed to be un-phased, and peered over the edge of the rail toward the gravel ballast under the track.

Then, just as it seemed inevitable that the bird would be crushed flat beneath the steel wheels under the locomotive, a small mouse bolted from beneath the rail ... and the bird leaped from the track and pounced on the mouse, lifting it off the ground and flying away with it.

I had just seen my first Northern Pygmy Owl!
http://en.wikipedia.org/wiki/Northern_Pygmy_Owl

This photograph has been provided by Andy Cassidy who lives in the Vancouver Area.  Andy caught this Northern Pygmy Owl feeding at.... yes, his backyard bird feeder!!!  And it wasn't there for the seeds.

The conductor said that the little fellow is often out there sitting on a rail, waiting for the train to come along.  The noise, bright lights and ground-shaking vibration caused by the big locomotives clawing their way up the mountain, causes the prey to panic, break and run for it. The little owl was waiting for this moment and capitalized on it.   The rodent and the owl disappeared into the darkness beside the engine.