Our goal is to operate the Pacific &
Eastern in a prototypical manner and one of the major concerns on the
full sized railroads is keeping trains a safe distance apart.
We've all seen graphic evidence of the results of two trains trying to
occupy the same space at the same time and it's not pretty. Over
the years railroads have developed a system of Operating Authority to
allow trains to move safely over the line and keep them
separated.
A
Brief History of the Evolution of Operating Authority
Timetable and Trainorder (TT&TO):
Back in the glory days of steam, trains ran on a published schedule
with strict rules regarding where they could be at particular
times. The telegraph was the main means of communication between
stations. Station agents would "OS" (on sheet) by telegraph when
a train passed through their station so that Dispatch and other
stations down the line could keep track of trains. If a train got
behind or there was an extra, Train Orders were hooped up to passing
trains giving them instructions to do things at times and places
outside of Timetable direction. The Timetable gave a train the
authority to move down the line and the Trainorder modified that
authority as conditions changed. With many trains moving over a
single track line, this could become cumbersome. Misreading a
trainorder, and it was easy to do, could lead to disaster. So,
railroads implemented a signal system to provide an additional layer of
protection. The most basic signal system is Automatic Block
Signals (ABS) such as we use on the P&E. So, if you had a
authority from the timetable or a trainorder and the signal was green
you went. But, it didn't matter what the signal indication was if
the timetable held you at a station until a particular time and there
was no trainorder directing you to do otherwise. The TT & TO
continued to be the authority, not just the signal system. Today,
it's rare to see TT&TO in operation except on tourist
operations.
Interlockings: Where
tracks crossed or lines merged, there was often more complex trackwork
and a tower was built with an operator who manually controlled both
turnouts and signals. We've all seen pictures of towers with a
bank of large levers to throw switches and signals. The switches
and signals were interlocked so that only one route could be aligned
through the plant at a time. Authority through Interlockings was
granted by signals set by the towerman. He controlled all
movements through his plant. There are no Interlockings on the
P&E, existant or planned..
Centralized Traffic Control (CTC):
As communications improved, it became possible for a dispatcher to
actually control the position of switches and the aspects of signals
along the line from a central location, typically a Division
Headquarters. When the Dispatcher was ready for your train to
proceed, he gave you the signal and away you went. In CTC
territory the signal indication becomes your Authority to
proceed. Signals in CTC are also used to direct trains into
sidings, overtake other trains and protect MOW crews working out on the
main line. In CTC, ABS is overlaid so that a Dispatcher cannot
inadvertently line trains into each other. The SP main on either
side of Klamath Falls is CTC, but not in the yards. On the
P&E there is no CTC, with the closest CTC signal being at the west
end of the SP main, below Texum (where the track disappears into Mt.
Helix).
Basic
Authority in the Modern Era
As radio communications
improved two newer forms of authority emerged,
DTC and TWC. Both systems rely on the use of radios and more
recently cell phones, to grant operating authority over a sections of
track. Both systems involve a communications between the
Dispatcher and the Conductor/Engineer where a form is completed and
read back for accuracy.
Direct Traffic Control (DTC): A
fixed section of track, often between sidings, is marked with signs
denoting the beginning and end of that particular "Block". A
block may include all or part of the main through a station with a
siding. Authority is then given, usually by radio, to operate
through a given block or series of blocks. Sometimes, joint
authority may be granted with other trains or maintenance of way.
Joint Authority implies reduced speed and keeping an eye out for other
trains and MOW crews. DTC was the operating authority of choice
on Southern Pacific's branch lines. But, as with TT&TO signal
aspect alone did not convey authority.
Track Warrant Control (TWC):
TWC relies on mile posts and/or station names/and or speficic points
(e. g. East Switch Derby) to grant authority
It's otherwise similar to
DTC. Both systems can direct traffic into sidings and allow for
various contingencies with assorted lines on the forms. TWC is
more flexible than DTC, in that a train may be given many miles of line
with just "from MP ABC to MP DEF" or segments of track much shorter
than typical DTC blocks may be authorized as conditions require.
GN, SP&S and BN all use(d) TWC for their non-CTC equipped
lines. And, once again, on signaled lines, TWC grants authority,
not the signal aspect.
Yard Limits: Being
within Yard Limits constitues a form of operating authority in and of
itself. Yard limits
are not controlled by Dispatch, but rather by the Yard Master, when on
duty. All moves are to be made at restricted speed with each
train watching out for other trains and personnel.
On the P&E, there are several sections with Yard Limits. Each
are or will be noted with a large yellow "Y" sign, although for now,
yellow posts suffice for yard boards.
From West to East:
- Siskiyou Staging -- Southern Pacific yard up to about half way to
where the line breaks through into Medco. The SP Yard Master is
in charge of this area.
- Medford/White City -- P&E from where the SP authority ends
half way down the north wall, through Medco and Crater Yard, through
White City and to just before Nick Young Road before Eagle Point.
The Crater Yard Master is the contact for the Crater Yard area.
If the Medco switcher is out working, he's the contact before
proceeding through Medco. And, if the White City switcher is
working, he's the contact for trackage around White City.
- Butte Falls -- From just east of McNeil Creek trestle to part way
up the hill to the tunnel. When the Butte Falls turn is in town,
he's the contact. When he's not around, proceed at restricted
speed.
- East of Keno to end of the line -- From the East Switch at Keno
(bottom of the helix), on through Pelican Yard and across Lake
Ewanua. The Pelican Yard Master will coordinate movements through
this area. If the Klamath Mills job is out between Pelican Yard
and Keno, he'll need to be contacted as well.
Once the P&E crosses Lake Ewauna, it ends with both wye tracks
switching onto the Southern Pacific main line. The SP main is in
Yard Limits also, so authority to enter the main must be grated by the
SP Yard Master. The SP main at this point is ABS territory so all
rules as pertaining to signals apply. There will likely be one
addition to ABS rules. Some signals, especially when crossing
over the SP main to enter the SP or BN yards, may display a flashing
red aspect. Flashing red is
Proceed
at Restricted Speed as opposed to a hard red dictating Stop and
Proceed at Restricted Speed. This is to facilitate movement
across the SP main without unnecessary stopping.
To access the BN trackage in Klamath Falls, one must first get
authority from the SP Yard Master to enter the SP main and cross over
to the switching lead (middle track). Then the BN Klamath Falls
Yard Master must be contacted for authority to enter BN trackage.