AMOSSG/4-SN No. 12

Appendix

APPENDIX

RELEVANT REGULATIONS CONCERNING THE REPORTING SCALE OF RVR IN METAR/SPECI

1.	ICAO Annex 3, Fourteenth Edition, July 2001

1.1	Para 4.12.7:

—	"The reporting scale shall consist the increments of 25 m for runway visual range below 400 m, increments of 50 m for runway visual range between 400 m and 800 m and increments of 100 m for runway visual range above 800 m. Any observed value which does not fit the reporting scale in use shall be rounded down to the nearest lower step in the scale."

Note.— See also ICAO Doc 9328-AN/908; Manual of Runway Visual Range Observing and reporting Practices, sec. edition - 2000, amendment 1, regulation 11.4, Steps of reporting scale and table 11-3.

2.	WMO No 306, Manual on Codes, 1995 edition, FM 15 METAR/FM 16 SPECI

2.1	Para 15.7:

—	"The groups RDRDR/VRVRVRVRi and RDRDR/VRVRVRVRVVRVRVRVRi

Note.— No regulations or reporting scale is available for the encoding of the group under
conditions, where the visibility has values up to and including 800 metres.

Description symbolic letters VRVRVRVR Runway Visual Range, in metres (FM 15,
FM 16) "Values up to and including 800 metres shall be reported in steps not greater	than 60 metres but not smaller than 25 metres, and those above 800 metres in steps	of 100 metres."

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