Originally Posted by
jmmoric
We had a long discussion with carriers about wind given by ATC, when it comes to velocity, so far it sits with:
We will provide the latest wind direction and velocity, icluding variations to velocity of 10 kt or more.
We will update the information of wind, if the velocity changes by 10 kt or more.
So with a wind of 230/19 kt, and a maximum of 28 kt, the maximum will not be given. Changes to the wind will be given when it gets up to 230/29 kt.... which effectively mean, you may get the 230/19kt, and may end up landing with 230/28-37kt without any updates.
The reasoning from carriers was, that this span is included in the calculated limitations of the aircraft.
That's right, and as far as I can remember that protocol on the reporting of gusts in METARS has not changed in around fifty years. Reported wind speeds are, of course, mean speeds, unless annotated as gusts. As you imply, pilots should be aware that gusts less than 10 kt above the mean speed are simply not reported on METARS or ATIS, although they may be by ATC officers to individual aircraft on Tower frequencies. Similarly, be aware also that gusts can also be negative, i.e. the wind may drop temporarily and significantly below the reported mean wind. Again, a helpful Tower controller will warn aircraft of this.
As far as this discussion on GS-mini is concerned, the wind speed for insertion into the PERF page is always the mean wind speed. Inserting a gust speed would increase the Vapp by less than it would decrease GS-mini. That in turn would result in lower managed IAS readings throughout the approach.