Derail Operation -- *Pittsburgh Traction* Video shows this nicely!

[Jim Holland]

Greetings!

	The function of South Hills Junction changed over the years.  In PRCo
days the junction served as a relief point and trolleycars sat
unattended for a period of time (although I think it would be safe to
assume that this would be against the rules - don't get off the car
until the relief boards!)  I *suggest* that this is the *primary* but
not the only reason for the derails.
	With the advent of the lrvs and with the move of operations to South
Hills Village, reliefs are not made at SHJ and the cars are not
unattended so the real need for a derail has vanished.
	And if we argue that a derail is still need at the new SHJ to prevent
runaways, what about a car which safely passes the derail under control
only to *run-away* seconds later.  It can then be argued that there
should be several derails in the down-hill tunnel ride!

Fred Schneider wrote:

> So what does it matter.  When the Port Authority took over, the laws of
> physics changed.  Derails are no longer needed because cars cannot possibly
> run away on a 6 percent grade.  All of this is obsolete material!
> (Cynicism comes with old age.)

>                 -----Original Message-----
>                 From:   Jim Holland [mailto:pghpcc at pacbell.net]
>                 Sent:   Friday, February 25, 2000 6:43 AM
>                 To:     PRCo -- WP -- JTC -- The Big *3*
>                 Subject:Derail  Operation  --  *Pittsburgh Traction*  Video  shows  this nicely!

> Greetings!

> On 1999.12.16 at 09.31 AM Eastern time, John Swindler said:::::::

>	As for derail signal, center was red, but impression is
> that upper signal was white.  Would feel more comfortable if someone
> could check an old operator's manual rather then trying to rely on
> memory from 30+ years ago.

>	The video shows two different cars going thru the
> derail within about 5 minutes of each other.
>	The center light appears red.  It appears as though
> once the car has passed thru the switch contactor while the motorman was
> depressing the track switch toggle, the red light remains on while the
> light below it comes on.  Colors are not easily discernible on video unless
> head-on and this is somewhat from the side, but the intensity of the
> bottom light is quite strong and appears white.
>	John had previously indicated that there was a time
> delay before the switch set.  Within several seconds, both the red and white
> light go out and the top light comes on; this top light *might* be green.
>	As soon as the front truck is on top of the derail,
> the top light goes out and the red light comes back on.  When the trolley pole
> passes the contactor on the far side of the derail, the derail sets
> again for the *turnout-to-nowhere* - ie, derail!

James B. Holland
------- -- ---------
        Pittsburgh Railways Company (PRCo), June of 1949 -- June of 1953
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