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!
*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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