Originally Posted by
EXDAC
ICAO Annex 3 - Meteorological Service for International Air Navigation - says as below. The limit you mention, exists in b)2) only. It seems to me that the case discussed in the thread - VRB16KT - was reported according to b)3).
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4.1.5.2 In local routine reports, local special reports, METAR and SPECI:
a) the units of measurement used for the wind speed shall be indicated;
b) variations from the mean wind direction during the past 10 minutes shall be reported as follows, if the total variation is 60° or more:
1) when the total variation is 60° or more and less than 180° and the wind speed is 1.5 m/s (3 kt) or more, such directional variations shall be reported as the two extreme directions between which the surface wind has varied;
2) when the total variation is 60° or more and less than 180° and the wind speed is less than 1.5 m/s (3 kt), the wind direction shall be reported as variable with no mean wind direction; or
3) when the total variation is 180° or more, the wind direction shall be reported as variable with no mean wind direction;
c) variations from the mean wind speed (gusts) during the past 10 minutes shall be reported when the maximum wind speed exceeds the mean speed by:
1) 2.5 m/s (5 kt) or more in local routine and special reports when noise abatement procedures are applied in accordance with the PANS-ATM (Doc 4444); or
2) 5 m/s (10 kt) or more otherwise;
d) when a wind speed of less than 0.5 m/s (1 kt) is reported, it shall be indicated as calm;
e) when a wind speed of 50 m/s (100 kt) or more is reported, it shall be indicated to be more than 49 m/s (99 kt); and
f) when the 10-minute period includes a marked discontinuity in the wind direction and/or speed, only variations from the mean wind direction and mean wind speed occurring since the discontinuity shall be reported.
Originally Posted by
Joe R
This came up in a recent discussion. Tower/ATIS reported a wind of VRB with 16 knots. Do your operators have explicit regulations in the OM-As / OM-Bs how "VRB" needs to be taken into account and whether you are allowed to land?
In my outfit there is no explicit regulations but generally such a wind is considered as tailwind. So landing is not allowed.