Re: Signalling Questions in Brisbane?

["MattyQ" <mattyq1009@dingoblue.net.au>]

<signal_spotter@my-deja.com> wrote in message
8ju0m9$847$1@nnrp1.deja.com">news:8ju0m9$847$1@nnrp1.deja.com...
> QR <snip> (is) putting the home signals right on the points (ala
> NSW practice) therefore requiring the overlap to be proved before
> swinging it

This is not always the case. There are many interlockings where the running
signal protecting the points is a certain distance in the rear of the points
they protect. In almost all cases, a "Leading Shunt" signal is located at
the points. Take, for example, a crossing loop on the Gold Coast Railway.
Due to the 140km/h road speed, the home signal is approx 1200m to the rear
of the points and the overlap takes up all of that 1200m. A leading shunt is
located at the points. Starters are about 100m from the points which is
enough to warrant including the points in the overlap.

Designers of the GCR need shooting. They bluntly refused to allow "Warner"
routes in the home signal which prevents simultaneous entry. So now, where
trains are timed to cross and one is running a minute late, the other
usually has to sit outside at the home, wait for the opposing train to
arrive, wait for the points in the overlap to time out, wait for the route
to set up then proceed into the station. This further delays the train about
3 or 4 minutes. In peak hours, that translates into about 3500 passenger
minutes lost.

Apparently this was done because the designers didn't like the idea of
Warner routes in 140km/h territory. HELLO!!!!!!!! Dynamic Speed
Indicators!!!   Speed proving!!!  Approach clearing!!!  SAFE!!!

(Note to Ian Signaldesignengineer - I would disavow any affiliation with
this design if you want to maintain your credibility!!!)

--
Matt Smith
Brisbane Australia.

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