Fwd: N&W Train Order Signals - "Calling On"
nw-mailing-list at nwhs.org
nw-mailing-list at nwhs.org
Sun Sep 24 20:13:05 EDT 2006
I am still trying to digest all this! Wow, what a bunch of information!
nw-mailing-list at nwhs.org wrote:
We call them "call on" signals. They are still in use today. I have them on
the westbound signals at Arthur and Montgomery. If trains are moving back to
back we can use the "call on" feature and get a "Restricted" signal into a
block that is already occupied by a train moving in the same direction as
the requested "call on" signal. I also have a "call on" signal at the west
end of Whitethorne (the west end of Whitethorne is now called "VPI Farm")
that I use to put the pusher up behind coal trains. It gives the pusher a
"restricted" signal into the block with the coal train and saves us from
having to block the switch and talk the pusher in behind the coal train
"according to the rule".
> >From: nw-mailing-list at nwhs.org
> >Subject: RE: N&W Train Order Signals - "Calling On"
> >On IX/XV/MMVI, scrivit Donizetti Tretelli:
> > >>
> >... The N&W also had a third arm (green in color) on some home
> >signals, and used it as the "calling-on arm."
> > >>
> >A "Calling On Signal" was also called a "follow up signal" or a
> >"come along signal." It is a signal displayed when the system of
> >interlocking does not allow for the display of a "good" proceed
> >signal, for instance when the first block in advance of the
> >interlocking is occupied. In essence, it allows the leverman to
> >"manually override" the interlocking system, and move a train even
> >when the system says "no."
> >It goes almost without saying that "Calling On" signals were/are
> >found only at interlockings.
> >The "Calling On arm" (if there was one provided) was always the
> >bottom arm on the semaphore mast. Frequently it was shorter than
> >the other arms above it (due to the fact that any train which would
> >received a proceed indication on this arm would be either stopped or
> >approaching it at a very low speed, and thus no great "range of
> >readability" was required.)
> >If no Calling On arm was provided on the signal, and the leverman
> >needed to advance a train, the rule required him to use a hand
> >signal with a lantern or flag or a certain color, and sometimes
> >issue a Clearance Card for the train.
> >A bit of background may assist here. The 1905 N&W Rule Book
> >contains no signal aspects and does not mention interlockings, which
> >to me says that the only signals on the railroad were simple
> >semaphores located at telegraph offices and that if there were any
> >interlockings on the N&W at that time, they were covered by Time
> >Table Special Instruction. The 1917 and 1930 Rule Books and heavy
> >on interlockings and give quite specific instructions and a full
> >list of signal aspects. Also, remember that this is before the days
> >of "remotely controlled" interlockings, and that almost every
> >interlocking was controlled from an on-site "tower" where there was
> >an operator/leverman on duty "working the levers."
> > The 1930 N&W Rule Book deals with "Calling On" signals in Rule
> > 906: "Slow speed permissive signals, when used at interlocking
> > plants, are attached to the semaphore mast of home signals below
> > the other signal indications, when home signals are used as block
> > signals, in addition to their function as route signals. They may
> > be either semaphore or position-light type and distinguished from
> > the regular home signals as shown in aspects. When displayed in
> > Proceed indication, it will indicate that the route through the
> > interlocking plant is properly lined up, but that BLOCK IS
> > OCCUPIED, and enginemen must proceed at restricted speed prepared
> > to stop short of train or other obstruction. Levermen must not use
> > this type of signal except when necessary to relieve or avoid
> > congestion within the limits of interlocking plants."
> >By contrast to the rather full and explicit 1930 rule quoted above,
> >the 1917 Rule Book gives a very simple rule to cover the same
> >thing. Rule 902 says: "A horozontal position of arm, or red
> >light, indicates Stop; a vertical position of the arm, either below
> >or above horizontal, or a white light indicates Proceed; a diagonal
> >position of the arm, either below or above horizontal, or a green
> >light, indicates Proceed with caution." <> >1917 the standard signal colors are not what we know today. Red was
> >used for Stop, but white was used for Proceed, and green was used
> >for Caution. The change from standard signal colors White/Green/Red
> >to Green/Yellow/Red was probably made very shortly after the 1917
> >Rule Book was issued.>>
> >What are the situations where display of a "Calling On" signal may
> >be necessary? (1) To put an assisting engine up against the rear
> >end of a train occupying the first block beyond the
> >interlocking. (2) To get an engine which has cut away from its own
> >train, "back against" its train (which is called an "engine return"
> >situation.) (3) To put a train into a block which is already
> >occupied by another train (which is called a "follow up"
> >situation.) (4) To put a train into a block where there is a "TOL"
> >(track occupied indication) due to a broken rail or similar cause.
> >How was this done in the interlocking tower (or at the "control
> >station," as da Hawss likes to call it in his Roo' Book these days) ?
> >(1) In the days of mechanical signaling, the display of a "Calling
> >On" aspect was accomplished by the manual operation of a lever which
> >pulled the "Calling On" arm on the signal to "proceed"
> >position. (Some railroads required that the leverman get permission
> >from the train dispatcher before displaying the Calling On arm,
> >because something was being done that the interlocking system did
> >not provide for.)
> >(2) At an electrically or electro-pneumatically operated manned
> >interlocking, the display of the "Calling On" aspect was usually was
> >done by depressing a large button located in the frame of the
> >machine, and almost flush with the front surface of the cabinet and
> >directly behind the signal lever, and then operating the
> >lever. (Other arrangements may have varied, but the above is my
> >experience with US&S machines.)
> >(3) On CTC machines of the US&S type, the display of a "Calling On"
> >aspect was usually accomplished by depressing a "calling on
> >button" below the signal toggle lever. I have seen machines where
> >one button was used for both "Calling On" and "fleeting" signals...
> >When depressed, it "called on," but when latched in the pulled out
> >position, it "fleeted" the signal. But I have also seen CTC type
> >machines where there was no "come along button."
> >In today's world of electric signaling and CTC, train dispatchers
> >give and crews act on "Calling On signals" all the time, but have no
> >idea of the significance, development or history of the
> >concept. Train Dispatchers don't have to deal with the concept of
> >"Calling On" because the control system itself deals with all the
> >variables. When a crew receives a "Restricting" signal aspect at an
> >interlocking today, it could be a "Calling On" situation.
> >The term "Calling On" is now almost lost from the vocabulary. The
> >last time I heard it used by an active railroader was one night in
> >the mid-1980s when I had duty in a tower during the detours
> >associated with a wreck. The operator told the train dispatcher
> >that he could not get a certain signal and the train dispatcher
> >replied, "Then Call Him On !"
> >There is an informative ICC accident investigation report in the
> >NARA archives concerning a wreck which occurred at Walton in the
> >1920s caused by the profligate use of the "Calling On" arm of the
> >eastbound home signal. Unfortunately, the on-line NARA website is
> >"down" as I write this and I cannot give the details from
> >memory. But the gist of the wreck was that the leverman had a new
> >"Calling On" arm on his home signal, but little guidance on how to
> >use it. With a train in the block just east of his tower, he gave
> >the "Calling On" signal to a following train, and the engineman
> >"took off" and ran into the train ahead, which was stopped at Walton
> >Transfer. If you can get that report, it will tell you a lot about
> >"Calling On" aspects.
> >So, Don, I hope I have not again told you how to build a watch when
> >all you asked for was the time of day. But you guys seem to like
> >reading the history behind all this stuff, and I certainly enjoy writing it
> >-- abram burnett
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