Monday, April 22, 2019

Appleford to Big Timber: 06:26 - 06:59

Running #420, the Upbound Freight, on the Daylight Pass Railroad

October 20 1954: 06:26 – 06:59

Without waiting for the station agent to clear them for the main, (the time-table they are operating under already does that as long as the semaphore is down and their departure time has arrived.) #420 is rolling through the east switch at 06:26, just 5 minutes after the Upbound Express departs going the same way.

This is cutting things close, closer than most railroads will allow, but if the Freight doesn’t get a move on it may not leave enough time for its switching duties at Big Timber before the Downbound Express gets there. Besides, the speedy Express is already a mile and a half mile up the line and gaining. it’s going to take a while to get the freight up to speed, and even that is still quite a bit slower than the Express, so there is no chance the freight will catch up unless the Express stalls. Even if that happens, at the slow speeds the Freight runs there will be plenty of time to get it stopped, especially since the Express operator knows they are coming and will be flagging the rear* if that happens.

*Or more likely, have one of the younger, and more spry passengers do the flagging for them since the Express Operators tend to be old men with tons of seniority. The up and downbound Express’ meet at Rockhouse and the operators will swap with each other there. The Daylight based operator taking over the Downbound Express while the Three Creeks based operator takes over the Upbound Express. This will have both operators back at their respective homes by 09:00 where they will have the rest of the day to themselves until they report for the evening run at 17:00. Again, they will swap places at Rockhouse and each will be back home for the night by 20:30. This schedule pays less than 8 hours a day but since they are hauling passengers, they are paid at a higher rate, and operating the high-priority, lightweight Express’ with no switching, and no ‘going into the hole’ to wait for higher priority traffic to go by, is about the easiest job on the railroad.

As soon as they clear the switch and recover Dean who has had to reline it* Tom sets about getting the train up to speed and setup while also performing the required running brake-test. At the same time Jake shuts off the blower, adjusts the flame, and keeps an eye on the boiler pressure and back there in the depot the day-shift station agent calls down to the dispatcher.

*Switches have a through route and a diverging route. The through route is normally straight and the diverging route is curved. (One exception to this is the equilateral, or Y switch on which both legs are curved, but the DP has none of these, not even on the Y up at Cutoff.) The bible of just about every railroad, including the DP, requires that switches always be left lined for the through route when the crew is finished with them and it’s the train-crew’s responsibility to see that happens.

“OS Appleford,” the agent says loudly into the phone’s mouthpiece, and hence into the dispatcher’s ear who has an open line to all the OS’s, “show number 420 departed eastbound at 06:26”

Down at his desk in the Goat Crossing yard office the dispatcher, wearing a headset with boom-arm microphone attached, responds “DS showing number 420 depart Appleford 06:26,” while at the same time making a notation on his train-sheet then moving  the magnet representing Upbound Freight #420 from the Appleford dot to a spot just to the left of the Upbound Express magnet already on the line connecting Appleford and Big Timber on his steel backed schematic of the railroad.

By the time all this behind the scenes work is finished Ronald is back on his perch on top of the tender, and since he is the only crewmember riding backwards, is the only one that notices that, though the freshly risen sun hasn’t yet chased back the shadow of the mountain here around Appleford, it has turned the San Andres range far to the west a light golden color.

“It’s getting towards the end of the month so remember to watch for torpedoes,” Tom hollers across the cab to Jake a few miles later as he keeps an eye out for the white W post that lets him know to start whistling for the level-grade crossing coming up that is protected by nothing but stop signs and crossbucks.

Most every engineer has, and will, run something over during their career, and Tom is no exception. The sound of metal being crumpled and shredded as an engine hits a vehicle and drags it along is bad enough, but when the collision is between engine and animal, or especially engine and person, the meat-grinder sound of flesh and bone being ground up in the running gear is the stuff of nightmares.

The experience, no matter how many times it happens, (Four in Tom’s 24 years in the right-hand seat, 2 relatively minor injuries by some miracle, 1 arm amputation at the elbow, and 1 fatal.) is not a pleasant one, tending to stick with a man for the rest of his life and populating his dreams, but there are some members of the public that just don’t grasp the concept of railroad right of way and use the tracks like a city sidewalk, or don’t understand that when hundreds of tons of train verses a couple tons of car, the car is going to lose every time.

In the crew lounges or bars you will, in the aftermath of one of these incidents, hear railroaders hoarsely cracking that removing people like that from the gene pool is a service to human kind, but that morbid humor is simply the same defense mechanism you get from cops and ambulance drivers, and behind the obligatory and half-hearted laughter they are usually hurting.

Fortunately, once past Goat Crossing there just aren’t that many people up on the mountain except around the depots where the trains run little faster than a walk anyways. And once you get outside of Daylight the DP main-line has very few grade-crossings, and this one coming up, where the new highway crosses the tracks for the third time, is the last until they are approaching the outskirts of Three Creeks, and that one is a mostly unused rocky trail to an abandoned cabin. But being the last easy access to the tracks, this crossing coming up also makes it a popular spot for the company weed weasels* to set up a test. They like the idea of a leisurely drive up the highway to the crossing so they only have to hike the tracks a short distance in either direction to get set up.

*The people charged with ensuring that other employees are complying with the stacks of rules and regulations that abound on railroads have a whole lot of names, weed weasel, for their habit of hiding in the weeds to spy on crews, is one of the mildest.

The Federal government require a certain number of ‘tests’ per month and since weasels, the kind that work for the railroad anyway, tend to be lazy buggers, they procrastinate until the end of the month starts looming then suddenly cram in their full quota in the last week or so, and this is why Tom reminds Jake to watch for torpedoes.

Torpedoes are small packets of explosive that can be strapped to the top of a rail with a pair of soft metal straps. When run over by a wheel they go bang, much like a cap in a toy gun but a whole lot louder. They are used to warn approaching trains of an issue on the tracks ahead. The noise alerts the engine crew to run at ‘restricted speed’ which isn’t a set speed limit but a requirement that the train be run at such a speed that it can be stopped in half the distance they can see down the tracks.

When conducting this particular test the weed weasels will set out torpedoes, usually two of them spaced close together to ensure the crew hears them but some weed weasels will only put out one, even though on the DP this sort of adversarial behavior is discouraged. Then they move down the track a ways, (After running over a torpedo the engineer is required to maintain restricted speed for a minimum of two miles.) often just around a curve where they can’t be seen until the train is close, and set a fusee or red flag in the track. The engineer must stop his train before running over either. Failing to do so will usually get you an unpaid vacation.

This morning no weasels are out and about, at least not here, but just beyond the grade crossing is a sharp dip in the track where a short trestle crosses a river, (In this parched part of the country it doesn’t take much to qualify as a river, but regardless, this trestle should have been raised and rebuilt years ago to level out the track.) which forces Tom to put a light set on the brakes while bailing off and pulling with the engine to prevent the slack running in as the cars free-fall down the dip behind him then slamming back out as they are dragged up the other side. This, of course, is not good for maintaining speed so he releases the brakes as soon as the house-car is on the trestle, which marks the bottom of the dip.


As #420 climbs up out of the dip we’ll leave the crew to their duties for a moment to discuss the braking system on a train, which can be confusing at first since it seems to operate backwards. And on top of that has a couple idiosyncrasies not seen on automobile brakes which can get the engineer into trouble if not paid attention to.

The automatic brakes on a train use a reduction in the pressure of the train-line that runs the full length of the train, called the brake pipe on some railroads, to set the brakes by signaling the triple-valve on each car to use air from that car’s auxiliary reservoir to pressurize the brake cylinder, setting the brakes. The major advantage of this seemingly upside down logic is that if the train breaks apart for any reason the train-line also breaks, releasing all its pressure and automatically setting the brakes.

The heart of a train’s braking system is the triple-valve found on every car. It has been improved several times since Westinghouse was granted a patent for the first example in the mid 1800’s, getting more complicated each time, but in a greatly simplified explanation of how it works, the triple-valve wants to maintain a balance between the pressure in the train-line and the pressure in the auxiliary reservoir on each car.

In the illustration above the pressure in the train-line has been reduced below that of the auxiliary reservoir. The higher pressure of the reservoir pushes the slide which is the heart of the triple-valve to the right, opening a port that allows air from the reservoir to enter the brake cylinder. When the pressure in the reservoir drops enough to equal that of the train-line the slide is nudged back to the left just enough to close the brake cylinder port. If the train-line pressure was dropped by a little bit the brakes are applied with a little bit of force. If the pressure in the train-line was dropped by a lot the brakes are applied with a lot of force.*

*Here’s where the reservoir to brake cylinder relationship of 2.5 to 1 kicks in. if the reservoir is too large the volume of air that has to be released from it to equalize pressure with the train-line is more than the brake cylinder can accept and the brakes would be slammed on full no matter how small the pressure reduction in the train-line. Conversely, if the brake cylinder is too large relative to the reservoir the brakes can never set hard.

When the pressure in the train-line is higher than that in the reservoir, such as when releasing the brakes by raising the pressure in the train-line, the slide valve is pushed to the left.  This does two things. First it connects the brake cylinder port to the exhaust port, releasing the pressure in the brake cylinder and allowing the spring to push the brake-block back off the wheel. Second it opens up another port called the feed groove that allows the train-line to slowly re-pressurize the auxiliary reservoir * and get it ready for the next brake application.

*This has to be done slowly otherwise the rush of air from train-line to auxiliary reservoir causes a drop in the train-line pressure which sets the brakes all over again!

The maximum amount of brake application with the 70 pound train-line pressure used on the DP’s Consolidations is 50 pounds in the brake cylinder achieved with a 20 pound reduction of the train-line pressure. At this point the pressure in the auxiliary reservoir and the brake cylinder is the same 50 pounds and reducing the train-line pressure any more has no effect on the amount of braking force. In virtually any case a 20 pound reduction is more than enough to stop a train. (A 15 pound reduction is usually the max an engineer will use and anything more than a 12 pound reduction is considered hard braking.)

OK, that’s how the automatic braking system on a train works, but buried in that description are a couple of idiosyncrasies that, if not paid attention to, can get an engineer into real trouble.

First off, with this system, though the brakes can be applied in a controlled manner, setting them in proportion to the amount the pressure in the train-line is dropped, there is nothing gradual about releasing the brakes on a train. In other words, if you have set the brakes too tight you can’t just lift you foot a bit and back them off a little like you can with a car. You have to release them completely then set them all over again, which leads directly to a second idiosyncrasy, namely, the engineer has a limited amount of air to work with.

Suppose the we’re rolling down a steep grade with a heavy train and use a full 15 pound reduction to hold the train, putting 37.5 pounds into the brake cylinders, (remember that 2.5 to 1 ratio of auxiliary reservoir to brake cylinder.) So far so good. We have 37.5 pounds in the brake cylinder and 55 pounds in the auxiliary reservoir. From here we can still dump an additional 5 pounds on the train-line if we have to and get the full 50 pound max into the brake cylinders and probably bring the train to a full stop - unless we’ve let the brakes get so hot first that they have lost their effectiveness.

But let’s suppose that isn’t needed and we successfully lower the train down the steep grade with our initial 15 pound reduction, but a bit further down the hill the grade eases off a little for a couple miles and we find that the amount of braking we have, 37.5 pounds in the brake cylinders, is too much here, even with the engine bailed off and pulling on the train in an attempt to keep it moving.

Since we can’t back the braking effort off gradually, we have two options, stop the train, tie it down with handbrakes, release the brakes, and start from scratch after letting the auxiliary reservoir pressure return to a full 70 pounds. Or we can keep the train moving by releasing the brakes completely and resetting them using the air we have left in the auxiliaries.

Choosing the first option means stopping the train for a good while, probably more time than the timetable might allow for, so, in order to keep the conductor, dispatcher, and road-foreman (The engineer’s boss.) off our backs we may be inclined to go for the second option.

But when we release the brakes the train is going to speed up quickly since it is still going downhill, and we need to reset them again, like right now! Only this time we’re starting with the reservoirs at only 55 pounds instead of the full 70 pounds because we can’t keep the brakes released long enough to pump the reservoir pressure back up.

Even with a reduced pressure, when we make a 10 pound reduction on the 55 pounds of pressure we has left we still gets 25 pounds in the brake cylinders and the train speed is back under control.

But don’t get comfortable yet because it gets worse!

It’s not long before the grade steepens again, the train starts speeding up and there’s that right-hand curve coming up that we don’t want to fly off of, so we dump 5 more pounds. Now we’re back to the same 37.5 pounds in the brake cylinders that was keeping things under control on that first steep grade. But, with only 40 pounds left in the auxiliary reservoirs we have essentially used up all our braking power and have nothing left in reserve. So from here on out, if we need more brake we're shit-outa-luck!

This process of releasing and resetting brakes before the system can replenish the pressure in the auxiliary reservoirs happens often enough that there’s a term for it, it’s called ‘pissing away your air’.

For a few minutes it looks like things might be working out.  But the brakes, already hot, are heating up even more, which reduces their holding power and now we are on the verge of a runaway with only one  option left.

The AB brake system, which replaced the K brake,* is an attempt to account for this ‘idiosyncrasy’ of our train brakes by adding emergency reservoirs on each car along with a slightly more complex brake-valve. When sensing a rapid drop in the train-line pressure the triple-valves on these cars will dump the pressure in the emergency reservoir, so far untouched so still at 70 pounds, into the brake cylinders.

*The K brake, developed around 1900, was simply the original Westinghouse brake with all three components, reservoir, triple-valve, and brake cylinder, combined into a single unit. It did not improve brake performance or address any of the shortcomings of Westinghouse’s original design, but did simplify and streamline maintenance, though if any one part went bad the entire unit had to be replaced, so in practice it actually drove up maintenance costs. The AB brake, which did address one major shortcoming of the Westinghouse and K brake, (As well as going back to the separate components stratagy) was developed in 1930 and by 1953 was required on all interchange cars. The trick here is that at this time (1954) the DP still owns many cars built with K brakes that they can still run because they don’t interchange them with any other railroads.

Assuming there are enough AB cars on our train all we have left in our pocket now is dumping the last of the air out of the train-line in a last-ditch effort to get stopped.  If we're lucky that last desperate pressure reduction will be rapid enough to trigger the emergency reservoirs to dump their air into the brake cylinders on enough cars to get the train to stop.

Except –

To activate the emergency reservoirs there has to be a rapid drop in the train-line pressure, it doesn’t really matter how much pressure is dropped, just that it drop in a big hurry. In the normal ‘service’ position of the brake control valve air escapes the train-line through a small hole, letting the air out slowly so the engineer can control brake applications, too slowly to create the sharp pressure drop that will trigger the emergency reservoirs. The ‘emergency’ position of the brake control valve has a big hole (Going into emergency is called ‘big holing’) which lets the air out of the train-line quickly enough to trigger the emergency reservoirs. – But the Consolidations don’t have an emergency position on their pre-AB braking system control valves so it doesn’t really matter how many AB cars are in the consist. The only way to trigger the emergency reservoirs on them is if Otis, way back there in his house-car with no direct communication with the engine, opens his big dump valve and the triple-valves see this last gasp of pressure escaping as a signal to go into emergency.

Of course, assuming it does work, going into emergency often means flattened wheels, broken couplers, damaged cargo, and sometimes even derailment.*

*Propagation delays due to friction delaying air-flow inside the train-line mean that the cars on the front of the train, closest to the engine where the pressure is first dropped, stop first while the cars behind are still going full speed, creating the same chain-reaction collision scenario you get when the automobile in front stops faster than the following autos can, often with the same resulting mess. Or, if the reduction comes from Otis opening his valve, the cars at the rear of the train slam their brakes on first while the rest keep right on rolling. This is where couplers get broken.

To complicate the braking of a train just a little bit more, the engine has two different braking systems on it. The automatic, which works exactly like the brakes on the rest of the train by applying brakes when pressure in the train-line is lowered, and the independent which uses what’s called straight air.

Straight air means that pressure is taken from the main reservoir and fed directly into the brake cylinder through the independent brake valve. The advantage of doing it this way is that pressure can also be released from the brake cylinder in a controlled manner through that same independent brake valve, giving the engineer the ability to decrease as well as increase braking effort in a controlled manner, very important since the independent brake is used for train-handling, primarily controlling when and how fast the slack runs in or out.


When we catch up with #420 again she has a full charge of air in her braking system and it’s just about a mile and a half beyond the trestle-dip. About half way between Appleford and Big Timber

 Here the grasslands have been pretty much left behind, replaced by second-growth forest, mostly various pines and Douglass Fir, but with some hardwoods mixed in as well.

The area was heavily logged in the first few decades of the century, with a steady stream of loaded disconnects carrying logs down the mountain against an equally steady supply of empty disconnects headed back up. But the old-growth was eventually logged over, then in 1938 the massive sawmill down in Daylight burned down and wasn’t rebuilt, effectively ending large-scale logging in the area.

Over the past two decades the second-growth forest has been largely left alone and has filled in nicely. It’s a welcome change from the basin some 1500 feet below. This time of year the scattered hardwoods are putting on a show of color anemic by New England standards, but here in the southwest, highly appreciated.

The track-profile for the 7.8 miles between Appleford and Big Timber is similar to the track from Goat Crossing to Appleford. Initially the train is climbing a gentle grade of slightly less than 1%, but then it hits a steeper grade. Without the weight of the boxcar they left at Appleford #420 is quicker to accelerate and will not be slowed as much on the steep grade, but the difference is subtle because the car they left behind only lightened the train by about 21 tons, which still leaves them on the heavy side.

In addition there’s a long right-hand curve in the middle of the steeper part of the grade as the track nearly doubles back on itself while making the final push up to Big Timber. Curves increase rolling resistance and slow trains as flanges grind against rail* and the solid axles drag one or the other of the wheels, which is either turning too fast or not quite fast enough depending on whether it’s on the inside or outside of the curve, along the track. And curves on steep grades make it even more challenging to keep the speed up.

*The wheels are profiled, or 'coned', such that when running on flat and straight track the weight of the car above tends to center the wheels between the tracks and the flanges don't touch the rail, creating extra drag, but on curves the profile is not enough to keep the wheels centered and the flanges come into action by rubbing against the side of the rail.

This same "coning" helps the wheels, connected together by a solid axle, roll around curves without one or the other dragging. The wheels will naturally shift towards the outside of the curve which means the inside edge of the outside wheel, which is its largest diameter, is riding the outside rail while the outside edge of the inside wheel, its smallest diameter, is riding the inside rail. When that happens the outside wheel travels farther per revolution than the inside wheel, getting them around the curve without either one being dragged. But this only works when the curves are gentle, and not all curves on the DP are gentle!

Despite the challenges, when they ease off the main onto the west end of the siding at Big Timber, they are only running one minute behind schedule.

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