middle siding signals

NW Mailing List nw-mailing-list at nwhs.org
Thu Apr 20 09:16:12 EDT 2017

     Is there a westbound signal hidden by the passenger train?

     While this piece of railroad looks like all 3 tracks have bonded 
circuits, other parts of the system had center or passing sidings that 
were not, and often were designated as "running tracks". On late comer 
NKP, you could come off CTC via a power switch and enter the running 
track. Speed limits on them were up to 50 mph. At each end could be a 
bonded circuit a few hundred feet long. If it were occupied, a following 
movement entering the running track would get a "restricting" signal, if 
not a "diverging approach". Rule 99 was in effect on running tracks.


On 4/19/2017 10:39 PM, NW Mailing List wrote:
> Jim,
> I would suggest that the Restricting aspect is for a call-on signal.
> One would be looking downgrade when looking east at Villamont, so 
> grade signals would not apply, plus grade signals are automatics, 
> these are controlled (but note lack of "S" plate). They have a full 
> compliment of diverging aspects at point-of-switch to govern middle 
> track pull-in, so the middle track is bonded and signaled. A dark 
> middle track would rate hand-thrown turnouts and no signals.
> Actually, note that the track layout is not exactly symmetrical, but 
> favors an easier alignment/higher speed pull-in off of the eastbound 
> and standard crossover for pull-out to the westbound. One exception to 
> above is if a spring switch is on the pull-out, it must be installed 
> using the easier alignment and the signal would lack diverging aspects.
> Before the Virginian merger, I believe a train's worth of eastbound 
> loads were set off here (and further east?) to fill tonnage for 
> subsequent eastbounds. That is a whole lot of back and forth thru 
> controlled signals displaying Stop and Stay into occupied blocks of 
> the middle track and EB Main, so to cut down on phone traffic and 
> expedite matters, the dispatcher can override the Stop and Stay 
> indication with Restricting, called a "call-on" signal. The Pocahontas 
> Division was littered with these where pushers would routinely get on.
> Grant Carpenter
> On 4/19/2017 10:44 AM, NW Mailing List wrote:
>> Mr. Powers,
>> Thank you for your response.  I understand your comments on 
>> geography.  My remaining question is why would it be advantageous to 
>> allow an Eastbound movement to proceed at restricted speed on the 
>> East-bound main and not be advantageous to do so for an Eastbound 
>> movement on the West-bound main?  The layout of the middle siding 
>> appears to by symmetrical with respect to both mains and I am trying 
>> to understand why the signalling should be different.
>> Thanks for your help,
>> Jim Cochran
>> On Wed, Apr 19, 2017 at 8:26 AM, NW Mailing List 
>> <nw-mailing-list at nwhs.org <mailto:nw-mailing-list at nwhs.org>> wrote:
>>     Jim,
>>         A restricting signal indicates the right to proceed at a
>>     restricting speed. That aspect does not deal with geography, it
>>     deals with trains ahead and track circuit continuity. It sits one
>>     position above "stop and proceed", which only deals with trains
>>     ahead - you must stop and then proceed at a restricting speed.
>>     Below that is "stop and stay". If there is a yellow plate with
>>     the letter "G" on it below the signal head displaying "Stop and
>>     stay" on the mast, a train on an ascending grade can pass the
>>     signal without the stop, ready to stop short of a train ahead.
>>     All the above very fine delineations of keeping your speed safely
>>     in check.
>>         From the photo, I cannot tell what track the furthest EB
>>     signal controls. If it has a dummy mast to one side of it, it may
>>     control the center siding, and most likely be like an
>>     interlocking home signal and not have any aspect allowing a stop
>>     and proceed.
>>         Wm J Powers
>>     On 4/19/2017 6:54 AM, NW Mailing List wrote:
>>>     I believe the attached photo may show the West end of the middle
>>>     siding at Villamont (confirmation would be appreciated).  My
>>>     question concerns the East-bound signals that are visible. The
>>>     signal for the East-bound main is capable of displaying the
>>>     RESTRICTING aspect while the one for the West-bound main is
>>>     not.  In my understanding, one reason for the RESTRICTING aspect
>>>     was to allow a train to proceed without coming to a complete
>>>     stop on  a grade where it might have been very hard to start
>>>     again.  Since this stretch is signalled for bi-directional
>>>     running, why would the signal for the West bound main not also
>>>     be capable of showing RESTRICTING?  It seems like the grade
>>>     would have been the same for East-bound movements regardless of
>>>     which main they were using.  Any thoughts?
>>>     Thanks, Jim Cochran
>>>     Moderator:
>>>     http://www.nwhs.org/mailinglist/2017/20170419.midpasside.jpg
>>>     <http://www.nwhs.org/mailinglist/2017/20170419.midpasside.jpg>
> ________________________________________
> NW-Mailing-List at nwhs.org
> To change your subscription go to
> http://list.nwhs.org/mailman/options/nw-mailing-list
> Browse the NW-Mailing-List archives at
> http://list.nwhs.org/pipermail/nw-mailing-list/

This email has been checked for viruses by Avast antivirus software.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist6.pair.net/pipermail/nw-mailing-list/attachments/20170420/effeb16b/attachment-0001.html>

More information about the NW-Mailing-List mailing list