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!
Ben Blevins

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".

See ya,
Russell Dickerson

> >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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