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Boyington
30th Mar 2021, 14:39
Can someone please explain what is the 45m and 60 m highlighted in the chart.
Thanks
https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/774x1032/img_20210329_wa0014_7616d55eba183420ec40b3014b6b9eeb04354a67 .jpg

pattern_is_full
30th Mar 2021, 15:56
See labels above those numbers: FULL - ALS out

ALS = Approach Lighting System

If the ALS is fully working, the required RVR or visibilty is 45m - if the ALS is not working (i.e. "out") the required visibilty/RVR has to be 1200m

Reason being - the very intense approach lights leading to the runway threshold can be seen from over a thousand meters farther away than the regular runway lights, in fog, snow, or other heavy precipitation.

tradewind
30th Mar 2021, 18:40
When required, ceilings are depicted prior to the associated visibility. Ceiling is always shown in smaller size in front of the RVR or VIS.

Equivocal
31st Mar 2021, 18:36
Thanks tradewind. I'm only an ex-controller but it had me puzzled - good to have a sensible explanation.