[PRCo] Re: WP signals

[Edward H. Lybarger]

True, but I have every reason to believe they were vigilant. The safety
record supports it.

-----Original Message-----
From: pittsburgh-railways-bounce at lists.dementia.org
[mailto:pittsburgh-railways-bounce at lists.dementia.org] On Behalf Of Dwight
Long
Sent: Wednesday, November 24, 2010 12:05 PM
To: pittsburgh-railways at dementia.org
Subject: [PRCo] Re: WP signals

Ed

That would make sense and would be a good safety feature.  It would,
however, require vigilance on the part of the "signal maintainer" to replace
burnt out bulbs because it would increase the strain on the remaining lit
ones significantly.

Dwight

  ----- Original Message -----
  From: Edward H. Lybarger
  To: pittsburgh-railways at dementia.org
  Sent: Wednesday, 24 November, 2010 08:43
  Subject: [PRCo] Re: WP signals


  The left-hand operation was determined more by geography than anything
else.
  If it was safer to go left, they did.  Many of the LH sidings were along
  highways and at the foot of grades where there could be derailment issues.

  I suspect that WP used signal bulbs with a shunt that allowed a complete
  circuit to be maintained if a bulb burned out, just like the PCC cars do.
  They could not afford to have a dark block, and as Dwight says, there were
  very few accidents.

  Ed

  -----Original Message-----
  From: pittsburgh-railways-bounce at lists.dementia.org
  [mailto:pittsburgh-railways-bounce at lists.dementia.org] On Behalf Of Dwight
  Long
  Sent: Tuesday, November 23, 2010 8:38 PM
  To: pittsburgh-railways at dementia.org
  Subject: [PRCo] Re: WP signals

  Phil

  I don't know what the frame of reference was for this post, but I can add
  this:

  Yes, there were two "paddle" switches in the West Penn system--one turned
  off the lights in the section just vacated and the other turned them on in
  the section ahead. West Penn often operated their spring switch-equipped
  crossing sidings left-handed so that the motormen could lean out the door
  and throw these switches when located in the space  between the tracks.
  This, however, was not universally true.

  The system over the years presented very few problems from "signal
failure."
  But it was not a fail safe system.  Such a system would have had the
lights
  on constantly except when the block was occupied.  In that manner, signal
  lights out would have meant that a car could not enter the block.

  The biggest problem was that the lights were connected in series, just
like
  old fashioned Christmas tree lamps, and if one went out, all did.
However,
  the most likely time for one to fail was when first switched on from cold,
  and motormen were not permitted to pass into a non-lit section without
  dispatcher authority. The problem was mitigated somewhat by running the
  voltage at less than for what the lamps were rated.

  Second sections were rare on WP, but one could follow into the block on
its
  leader, maintaining visual contact but with sufficient distance to stop if
  the leader did.  The alternative, for a not-too-close following section,
or
  an excursion car, was to wait for the leader to vacate the block ahead
  (lights out!) and then proceed as normal, lighting up the block before
  entry.

  There were intermediate lights at places such as curves with limited
  visibility, etc, but this of course did not help the spacing problem with
  following moves, just alerted the motorman if an opposing car had ignored
  the crossing point and entered the block.

  Human error as well as electrical error was always a potential in a system
  as primitive as this.  However, on the up side, WP motormen were very
  professional, conscientious, and alert to their surroundings, the
schedules
  and normal crossing points, and the like.  Such a system would probably be
  asking for a collision with today's far less well trained and disciplined
  work force.

  What prompted this enquiry?

  Dwight
    ----- Original Message -----
    From: Phillip Clark Campbell
    To: pittsburgh-railways at dementia.org
    Sent: Tuesday, 23 November, 2010 19:59
    Subject: [PRCo] WP signals


    I assume that releasing the signals behind at a siding and
    activating the signals ahead were separate functions.  The
    drawing suggests they 'may' work simultaneously.  This is
    in regards to the manual signals.
    With 30-60 min headways there isn't much problem with
    following cars, just opposing.  Did this system of signals
    present many problems?  Did WP have cornfield meets
    from signal failure?

    How were signals handled when a second section was added
    to a schedule?  Did both cars occupy the single track at the
    same time?  Spacing could be a problem with all the curves.
    I could see the first car forgetting about the second section
    then shutting down the signals at the next siding.  This could
    allow an opposing car to meet the second section on single
    track.


     Phil
    Without  a   'coast'   but  not  a   'cause.'