NW-Mailing-List Digest, Vol 108, Issue 13

[NW Mailing List]

I have thoroughly enjoyed the series of Ron Davis track upgrade photos thru Roanoke. The process, the changes, the signals and all the other aspects that Ron points out have been both educational and enjoyable.


I have two areas of questions I would like to ask about and both are well shown in the first photo of Ron's most recent batch ... Roanoke Junction 5-3-2014. 


That photo looks east from the Tenth Street Bridge and offers a nice straight, heavily compressed shot to the point where the tracks split three ways ... up the Shenandoah, more or less straight ahead to Lynchburg and Norfolk, and right to Winston-Salem. 


I am not sure how the tracks are numbered here in real life and, to avoid confusion, for my question I will label the tracks from left to right A-B-C-D-E with A & B heading north up the Shenandoah toward Hagerstown, C & D heading east to Lynchburg and Norfolk, and E turning south to Winston-Salem.


For the most part, the switches in this photo are for crossovers which allow trains coming in from any track at the bottom of the photo to be able to proceed out on any track leaving the top of the photo. In addition to those crossover switches, there is a yard switch at the east end of track B just before it curves to the left, and then over on track C, the second switch from the bottom begins the second leg of double track heading toward Lynchburg. That switch strikes me as duplicitous to the crossover switch two switches farther up in the photo.


I have a hunch and I'd like someone to shoot it down or corroborate my guess.  Let us call the "duplicitous" switch C2 and the route-necessary crossover switch C4, both being on my C track and being the 2nd and 4th switches from the bottom of the photo. Also, for the sake of this question, consider that all trains are heading toward the top of the photo, tho they could be heading either direction. Here goes.


If train RO-LB on track A or B is heading to Lynchburg it would need to take two or one crossover to get on track C and, for this example, will stay on track C out of town. 


Train RO-WS on track C heading to Winston-Salem would need to wait for train RO-LB to clear switch C4 "if" switch C2 had not been installed. Because switch C2 is installed, both trains can operate without getting in each others' ways. So, I am guessing that the "duplicitous" switch C2 is not duplicitous at all because it is there to allow both trains to run at the same time. Is that close to what NS track designers were thinking or is C2 really duplicitous after all?


My other question involves two signal posts positioned between the large overhead 3-track signal bridge and the concrete bridge just to the east. Both single signal posts face oncoming WB trains (as 180-degrees opposed to the overhead signals). The signal to the right of track C seems to directly face track D. The signal to the left of track A appears to indicate for track A.


My questions here are:


1 -- Why are these "short" signals here and not on the other side of the concrete bridge? Are they short for visibility under the bridge? They are hardly visible in the west view from the people walkway. Or, are their short heights optical illusions due to the compression of the long lens?


2 -- To which tracks are these two signals sending signals?


Thanks for the assists ... Bob



Bob Loehne
8007 Maxwelton Drive
Huntersville, NC 28078
800-611-1218 
oezbob at aol.com 





 
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