Re: Crossing loop design (r.e. Southern Aurora crash)

[David Johnson <trainman@ozemail.com.au>]

Tony Gatt wrote:

> > Autos can also be straight up and down in NSW with a letter A underneath the
> > signal as seen on the East Hills line.
>
> I think ppl are talking about Auto only signals. Not Home signals acting as
> auto's..
>

There are situations where there is a reflective A plate on a signal.  These are
often at places that used to be home signal, but now aren't.  They are also used in
locations where space is at a premium - like the underground.

> You will find "permissive homes"  where the interlocking can be taken out of
> manual operation, Parramatta etc.. You will even find them at Circular Quay...
>

The Illuminated A lights in the underground are NOT there so that Sydney box can run
in auto.  They are put there, so that in an emergency, Sydney Box can turn off all
the A lights, and the signals will go back to stop.  No trains can trip past those
signals while the A light is out.

--
David Johnson
CityRail Guard
trainman@ozemail.com.au
http://www.ozemail.com.au/~trainman/