Re: "lost" trains

["nobody" <dweebken@NOSPAM.yahoo.com>]

The incidents don't always happen in electrified areas, though I've not
heard of many mishaps outside the electric system. The colision between a 48
class and an endeavor on the main south is an example of this, the supposed
"near miss" just after Glenbrook on the southern line is another. I know for
a fact that electrical circuits exist in signals well past the end of the
elecric system, paricularly up north. The Beresfield crash happened in an
area with electric signals (interesting to note the arm meant to trip the
brakes of a train which could have stopped the beresfield incident isnt on
that line even though it is one of the most busy and has the heaviest trains
in NSW).
The theory is a good one, however there are things it doesnt answer, like if
a locomotive disappears where there is none of the problems like you
mention. But it does answer other questions. The 1988 incident where an
interurban hit a train hauled by 3801 on the Cowan Bank was apparently
blamed on the use of sand on the locomotive preventing any short circuit.
Perhaps the old rail grinders that used to be attached to trains could see
service again! Not that a complete check of every wheel in NSW would go
astray.

Brendan

Brendan


"Keith Malcolm" <keithm@commslab.gov.au> wrote in message
keithm.48.38614947@commslab.gov.au">news:keithm.48.38614947@commslab.gov.au...
> with regard to trains, light engines etc "disappearing" from track
diagrams, I
> wonder if the sensitivity (or shunting) of track circuit relays might be
> significant?
>
> Perhaps shunting of the track by wet dirty ballast could cause false
operation
> of signals and "corrective action" involving reducing the sensitivity of
the
> relays might result in "lost" trains or intermittent false operation of
> signals.
>
> Also, is it significant that such events appear to occur (in NSW at least)
in
> the electrified area? (Perhaps there are no track circuits outside of the
> electrified area - I wouldn't have thought that to be the case.)
>
>
> Keith G Malcolm
> 23 Dec 99
>