Signal Question and rule term
NW Mailing List
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Wed Oct 30 23:14:33 EDT 2013
it seems there were so many variables for each circumstance, trying to match
a signal aspect for it was an impossibility.
Just as a general observation most signals reflect track circumstances such
as turnout routing but gives you a clue about speed to operate,
doing a double duty, how the railroad directly says those signal indicate is
put in the rulebooks and what to do.
Advance medium might say a turnout is ahead, but it could be a track
condition indication a speed to run and no turnout, such as its the end of
the track ahead, or a sharp curve, or just a 2nd railroad crossing.
These are just a general observations.
----- Original Message -----
From: "NW Mailing List" <nw-mailing-list at nwhs.org>
To: <nw-mailing-list at nwhs.org>
Sent: Wednesday, October 30, 2013 4:42 PM
Subject: RE: Signal Question and rule term
> I have never understood why "medium" came about for aspect names on the
> N&W. It sounded big-time? The term has little relevance to how the
> diverging aspects were applied in the field. "Diverging" always seemed
> intuitive and a better fit for the relatively basic signal system the N&W
> used. Thank you for the background! I even caught the tease about the new
> CTC equipment--what stuff?
> And please, write that article.
> Grant Carpenter
> > Date: Wed, 30 Oct 2013
> > The matter can be summed up this way: The N&W Operating Rules for 13
> years used the word "Medium" in the names of three of its signal aspects,
> but that word didn't authorize "Medium Speed" (30 MPH) over the turnout.
> The speed over the turnout was "as prescribed" in the Time Table Special
> > The >>ONLY<< N&W Rule Book which uses the term "Medium" in naming signal
> aspects is the 1951 Rule Book. (Those aspects are Approach Medium, Medium
> Clear and Medium Approach.)
> > There is one other key ingredient of a Speed Signaling system which is
> missing: the N&W never used "Slow Speed" (15 MPH) signals over switches
> having No. 10 frogs. Slow Speed signal aspects (Approach Slow, Slow Clear,
> Slow Approach) are entirely missing from all N&W Rule Books. Given that
> N&W had two arms on its home and distant Position Light signals, and
> lamp spaces on its Position Light dwarf signals, it would have been quite
> easy (and beneficial) to have given Slow Speed signals where required, but
> they didn't do it. Nor did the N&W ever use Limited Speed (40/45 MPH)
> > For these reasons, it would probably be best to say that the N&W never
> had a real Speed Signaling system, the use of the word "Medium" for a few
> years notwithstanding.
> > As someone on this List remarked a few days ago, the N&W clung to the
> "semaphore mentality."
> > In one way, not using the equipment they had to its fullest potential
> a waste. But in another way, they didn't need a Speed Signaling system.
> Their interlockings were not complex and they did not operate trains on
> close headways. They got by with a simple system that did what they
> > Remember the old K.I.S.S. principle? "Keep it simple, Stupid!"
> > Nonetheless, I would really love to get inside the head of W.P. Wiltsee,
> the Chief Signal Engineer in the 1930s and 1940s, to find out what he was
> really thinking... especially with some of that stuff he ordered on his
> CTC equipment in the 1940s !
> > -- abram burnett,
> > frustrated electron jockey
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