Middle Track Operation on the N&W

[NW Mailing List]

All this talk about the middle tracks is fascinating.  I'm amazed that the
middle track at Juniper is still there.

If the middle tracks were controlled by the towers, then the operator would
have to unlock the switches before a train crew could throw them if they
were Electric Lock hand throw switches, which I think they were before the
CTC conversion.  The US&S T-21 with Electric Locks and pipeline operated
derails were the standard appliance on N&W territory for decades.  Much of
that equipment was reused after the CTC conversions at industrial sidings.
They are almost all gone, but a few still remain in service to this day.

If anybody at the archives ever runs across any old signal department
prints of those towers, I could interpret the signal logic to figure out
how  they had it engineered to work.  But, I've yet to find anything
anywhere near that old.

Ben Blevins
 On Feb 4, 2014 5:21 PM, "NW Mailing List" <nw-mailing-list at nwhs.org> wrote:


> I am looking for information on exactly how the N&W operated its Middle

> Tracks.

>

>

> DEFINITION: A middle track was a track, located between two signaled main

> tracks, provided so that interior slow trains (freights) could get off the

> main track when they "fell back on the time of" a following superior train

> (e.g. a First Class train.)

>

> EXAMPLE of the Use of a Middle Track: Extra 2042 West, a tonnage train,

> leaves Elliston on the Westbound Main Line not far ahead of No. 25's time.

> Making a slow run up Christiansburg Mountain, the crew of Extra 2042 West

> pulls into the Arthur Middle Track and lets No. 25 proceed around them

> without delay. The crew of the Extra West does not have to be instructed by

> message or Train Order to do this -- the rule told them what to do. Rule

> 86: "Unless otherwise provided, an inferior train must clear the time of a

> superior train in the same direction not less than five (5) minutes; but

> must be in the clear at the time a first class train, in the same

> direction, is due to leave the next station in the rear where time is

> shown." (Over the years, there were all kinds of permutations on this rule,

> allowing Extra trains to run ahead of Third and Fourth Class trains, and

> the like, without clearing. But those permutations are not germane for the

> question I'm raising.)

>

> QUESTION: My question is this... What provision did the N&W make to

> prevent opposing trains from entering the same middle track at the same

> time, and coming to a nose-to-nose Mexican Standoff?

>

> ONE OBVIOUS SOLUTION is to provide "middle crossovers" (escape crossovers)

> somewhere along the middle track, and designate the east portion of the

> middle track for the use of westbound trains, and the west portion of the

> middle track for the use of eastward trains. This is what the N&W did on

> long middle tracks which had the capacity for holding two trains.

>

> ANOTHER SOLUTION would be to designate certain middle tracks as for the

> use of only eastbound (or only westbound) trains, "unless otherwise

> provided," which meant unless otherwise instructed by the Train Dispatcher.

>

> A THIRD SOLUTION, and the one I think the N&W used, was to provide some

> form of signal protection against opposing trains pulling into a middle

> track simultaneously. So that, if an eastbound had opened the switch to

> enter a middle track, the switch at the far end would be electrically

> locked and could not be used by a westbound for pulling into the same

> middle track. IT IS THIS THIRD SOLUTION that I am curious about... IS THIS

> WHAT THE N&W DID? HOW DID THE ARRANGEMENT WORK?

>

> Middle tracks generally went the way of the DoDo Bird with the advent of

> CTC, the reduction in passenger trains, and the era of "Stuart Saunders

> reductions."

>

> So, to REITERATE THE QUESTION, does anyone know how the N&W operated

> middle tracks NOT equipped with middle crossovers?

>

> Sorry for the longwinded question, but it asks about a situation which

> needs a rather full explanation.

>

> -- abram burnett

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