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

["David Proctor" <daproc@spam_this.umpires.com>]

Simon L wrote in message <36C2994C.CFC8B247@es.co.nz>...
>This raises an question of interest, namely what signaling schemes are used
in Aus.

NSW is simple - the top aspect tells oyu if you can pass THAT signal - the
bottom one gives you warning of the next one. It is historically interesting
(although irrelevant to this conversation - email me at daproc@umpires.com
if you want the info)  as to why this happened.

Basically - NSW has two aspect signalling in MOST heavily trafficked areas -
providing Green (G), Yellow (Y) and Red (R) in both aspects.

The basic stop signal is Red over Red (R/R) - prior to this, a driver would
receive a caution - G/R, indicating that he can pass this signal (upper
Green) but that the next signal was at stop (lower red) - before the G/R, he
would receive a G/Y - and before that a G/G - in some areas of limited
overlap, there would be two G/Y's in a row.

There is more to it than that, but I will leave it to our resident experts
to fill in the rest of the details.
(Over to you Dave Johnson!)

DaveP