Surface wind

[parkfell]

Quite often when the day is windy the Aerodrome Controller will pass updates on the surface wind after the landing clearance has been given.

Question : Are there defined variations in wind direction and/or speed which require updates to be given?
Is there any guidance as to when the last wind information is passed?

[niknak]

I'm not aware of any specific requirements, but if I am in the tower and having given landing clearance the wind varies by more than 10 deg or 5 knots, I'll pass it as an instant wind.
That said, if the pilot requests a "final wind check", that is precisely what they will get and no more.

Pilot input/comment would be useful.

[Sparkle]

If it's a very gusty day frequent windchecks from the tower are helpful all the way down.
If the w/v doesn't vary that much then frequent windchecks can become a bit of a nuisance. As with a lot of things you get a feel for it.

If the pilots don't acknowledge then they prob have their hands full. I usually doubleclick, so not to offend, as once happend.

[vintage ATCO]

Have to say unless the wind is varying greatly I don't bother unless asked. Most of our customers can tell me the wind is 203deg 42½kts at 652ft! Anyway the RT is normally busy and someone else is being told to continue with a wind check, it gets broadcast often.

[Sudden Stop]

I think that unless requested by the pilot, it'll come down to what the controller on duty thinks is relevant. If, as it's been said, it's gusty and the a/c has been cleared to land for a while (perhaps into a head wind), i'll give another check as the a/c gets closer or if there something significant (as niknak states), especially in crosswind or close to a/c limits situations.

[ecj]

1. The times it is useful to pass updates on the wind does to some extent depend upon the size/weight [sorry - mass] of the aircraft.

2. If the conditions includes gusts [as defined] and/or the direction is varying by more than say 20 degrees either side of the mean, this is also useful. But further updates are really only useful when there is a significant change to what has already been passed.

3. Continuous updates repeating no further relevant information is distracting below say 500 ft. You are now mentally prepared and can "feel" what the conditions are like, and if you want any update you can always ask.
Numbers tend to be irrelevent at that stage, unless of course it is a limiting wind of the aircraft concerned - either absolute maximum or demonstated cross wind limit.

4. Whilst the two minute average gives you a good idea of what to expect, instant winds are also useful.:oh: