Re: Signalling in Victoria

[Eddie Oliver <eoliver@efs.mq.edu.au>]

> I stand by my statement that the overwhelming majority of US roads use the
> GCOR. Add up the route miles and see for yourself.

Let's get the data and do exactly that? But we need to look at things
other than pure route mileage, e.g. traffic density.

> Conrail and CSX are the only 2 biggies that use speed signalling.

And they are only a trivial minority of the US scene, in your view? They
might well disagree, as would their tonnage statistics.

Virtually the whole of the eastern side of the country is NORAC, just
like the western half is predominantly GCOR. The Northeast Corridor, for
instance, is NORAC - and it is actually owned by Amtrak. 

> <<  whereas I say that it is route signalling only if
> there is an explicit indication of WHICH route applies (not merely that
> it is one of possibly several diverging routes) >>
> 
> And that is precisely what GCOR gives you. If there is more than one diverging
> route you get another light for that track, (top to bottom, left to right)

Examples of specific locations please? Are you saying there are some
four- or five-headed signals out there in GCOR territory?

What do you get going into (say) Los Angeles Union Station? 

> I don't know who you know in the US but for your information, I've never heard
> any train crew, road foreman, train master etc ever talk about "route" or
> "speed" signalling.

I was talking about signal designers and signal engineers, not running
staff. Obviously the question does not arise on any one road; it is a
comparative matter. There is no reason for (say) a road foreman to enter
into any categorisation about such a matter. However if you go for a job
on a NORAC or CROR road and try to tell them that you propose to run
their trains by GCOR, will you expect them to employ you?

> Although I would hope that signal designers are at least
> familiar with international conventions.

Indeed. 

> Your defintion of route signalling would be a little confusing in Victoria due
> to the existence of quite a few 3 pos. signals which do tell you exactly which
> route you are taking by means of a route indicator.

Indeed, so Victoria is nowadays effectively route-signalled in a few
places, e.g. parts of North Melbourne and entries into the underground
at Richmond Junction. It is a classic case of hybridisation, and since
they seem to be installing progressively more route indicators, they
seem to have decided that the route information is worthwhile having.

> Using your definition, VR 2 pos signaling was not route signalling because
> discs could take you many places and at some locations a home signal could take
> you to more than one location.

Labels of route and speed are not normally applied to what might be
called incomplete signalling systems, i.e. where neither speed nor route
information is conslusively displayed - and consequently one may have to
take pure shunting signals out of consideration in any such debate,
since they often contain much less information than do running signals.
For instance no one would dispute that NSW is route-signalled, but there
are some shunting signals (admittedly relatively few) which do not
convey route information. 

Similarly I think you would find that even in your GCOR context, there
are dwarfs (which we would call shunting signals) which can display only
slow speed indications with absolutely no route information; but despite
the general flow of this debate, I would not attempt to use that as
evidence to support the speed versus route distinction.