OverRun,
Then I trawled through the AIP online, and the aerodrome charts in the DAPs and they don't show it (links below for non-Oz PPRUNERs)
The AIP does indeed show the light spacing.
The Entry for Broom YBRM clearly states that the light spacing on Runway 10/28 is 90m.
You can see it for yourself at
http://www.airservices.gov.au/public...7-Mar-2005.pdf
Which is the appropriate part of the AIP for that kind of information.
When making an assessment of visibility for take-off, if one assumes that the light spacing is 60m then one will never be taking off with less than the required Visibility/RVR.
However, one must remember that an important part of the pilot assessment is that a suitable number of lights are visibile to enable the flight path orientation to be maintained. In that respect the spacing is meaningless. Thus any cockpit assessment must be based on having a suitable number of lights visible regardless of the spacing.
When departing from an aerodrome with no ATC, and no operations staff in poor visibility, how can one ensure in light winds and fog that a) There are no obstructions on the runway or b) some other pilot isn't counting the runway lights at the same time on the other end!
Where I spend most of my time, low visibility operations require safeguarding.
Regards,
DFC