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Freight Yards: What Are All Those
Tracks?
by Richard Lake
In the previous article I wrote about human factors
in freight yards. Before I get into the topic for this
article on yards, I want to direct your attention to the
January 1996 issue of the Bulletin, pages 29 and
30. Pat Harriman has two one-night projects which are
exactly the kind of structure I was referring to. If you
are looking for a simple project to add life to your
yard you can’t go wrong with either of these
structures.
As my personal struggle with layout design continues
there is another aspect of freight yards that every
modeler needs to consider. What are all those tracks
for? A large yard is a maze of track and switches and
the plan and purpose is hard to see. I remember my first
couple of weeks as a fireman in Armourdale as a time of
total confusion. I was never sure where we were, where
we were going, or what we were going to do once we got
to some section of the yard. This made it really
interesting for the switch crew the first time an
engineer allowed me at the throttle for some switching,
but that’s another story. The point of all this is
very simple. A major yard facility looks very confusing
but there is a purpose behind each and every track
within the yard limits and that purpose helps to
determine location, access and size for each track.
Receiving Tracks
The first set of tracks to consider in designing a
yard are the receiving tracks. These tracks do exactly
what the name implies, they receive inbound freight
trains. There should be at least two receiving tracks,
one for eastbound trains and another for westbound.
There may need to be more tracks if the number of trains
arriving each day is large enough that switching
operations will be unable to clear these tracks before
the next trains arrive.
Receiving tracks are located immediately adjacent to
the main line with easy access from the main into the
yard. If the main line is double track, there have to be
crossovers to allow trains into the yard. Also, the
receiving tracks must be located so that access from the
main does not block yard leads. In real life, railroads
want to get trains into the yard as quickly as possible
so that needed servicing and switching can be done and
the next train sent on its way. If movement into the
yard requires using a yard lead, the inbound freight
might be held up by switching operations, thus blocking
the mainline. Also, the time it takes for a long train
to move into the yard will tie up the lead and hamper
switching operations. Neither of these situations is one
that leads to efficient operation and on the prototype
would make the yardmaster and trainmaster very unhappy.
Receiving tracks should be long enough to hold the
longest train you intend to operate plus enough
additional length to allow for engine movement. Inbound
freights should be able to pull into the yard without
having to make a cut to double part of the train over
into a second track. Typically, any moves made within
the yard limits is done by a switch crew. Breaking an
inbound freight would take extra time and tie up the
yard. The additional room allows engines to cut off for
movement to the service facility. This means that there
also will have to be switches allowing access to a
runaround track for road power to escape from the
receiving tracks. Also, for those of us still operating
in the days when a caboose was always present, the
runaround track allows a switch crew to remove the
caboose from the train and set it out on a caboose
track. Once the road engines and caboose have been cut
off and are out of the way, the inbound train is ready
for switching. The road crew have done their job and now
the yard crews take over.
Train Yard
The departure yard in Armourdale was called the train
yard. It is really a yard within the yard and it is the
heart and soul of railroad operations. Classification or
sorting is done in the train yard, taking through loads
from the receiving tracks and new loads received through
interchange and assembling them into outbound trains.
Within the train yard some tracks may be designated east
and westbound to help clarify the direction the trains
will travel on departure. But the train yard has many
more tracks than just those designated for outbound
freight. Additional classification tracks are needed to
set out loads and empties for transfer to other roads,
for repair, or for delivery to local industrial sidings
or team track unloading.
The train yard lead needs to be as long as possible
to allow the switch crew to pull the maximum number of
cars out onto the lead for switching operations. The
fewer cuts that have to be switched the more rapidly the
switching operation can be accomplished. In the train
yard the tracks nearest the main line are usually
designated for outbound trains. Like the receiving
tracks, these tracks need easy access to the east and
west bound main line and in a way that does not tie up
the yard lead as an outbound train pulls out onto the
main. Ideally, departure tracks will be long enough to
contain the longest freight — but they don't have to
be. They should be as long as layout space will allow to
limit the number of tracks that have to be coupled to
make up that train. In railroading, time is money and
each time you couple on to another block of cars it is
necessary to pump up the air on the new cut. Also, while
doubling is going on, the train yard lead will be in use
which prevents switching operations. Yet another
complication to consider while coupling adjacent tracks
to make a train is this: the train yard lead and/or
track extending from the lead must hold the entire train
within the yard limits. An air test has to be completed
before you are allowed out of the yard, blocking the
main just isn’t done.
The number of tracks contained in the train yard is
dependent on a number of factors. The first factor is
the space available on the layout. If you have lots of
space for a yard, then long tracks capable of holding
entire trains is not a problem and you will need fewer
tracks. If space is at a premium, as it is for most of
us, then a larger number of shorter tracks becomes
necessary. The second factor to consider is the number
of departing trains. If you only plan to operate one or
two trains in a session, then two outbound tracks will
serve and it might be possible to get by with only one
designated departure track. If you plan to send three or
four trains out during an operating session then more
tracks are needed. A final factor that has to be
considered in yard design is where to place exchange
loads, local deliveries, etc. In a large yard, some of
the tracks in the train yard serve as temporary storage
for these cars but there would be a separate set of yard
tracks, known as the transfer yard, with its own lead to
complete the classification process before these cars
are delivered. The transfer yard is another complex
operation in its own right and so will have to wait for
another article. Until that time, keep the switch crews
busy and the trains running on time.
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