Passing winds
Thread Starter
Joined: Mar 2000
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From: You live where
Passing winds
All,
I am interested in what winds Tower controllers use when giving wind checks to arrivals and/or departures, either routinely or when the conditions are different to the ATIS?
Is it the instantaneous wind ? If so, what are the parameters for this (over what period is this measured)?
Is it the mean wind? If so, again what are the parameters for this (over what period is this measured)?
Can anyone explain the difference between a gust and a peak wind? Are the same thing?
I am interested in what winds Tower controllers use when giving wind checks to arrivals and/or departures, either routinely or when the conditions are different to the ATIS?
Is it the instantaneous wind ? If so, what are the parameters for this (over what period is this measured)?
Is it the mean wind? If so, again what are the parameters for this (over what period is this measured)?
Can anyone explain the difference between a gust and a peak wind? Are the same thing?
Joined: Dec 1999
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From: LHR/EGLL
In the UK we pass the 2 minute average wind.
We can give the instant wind if we think it appropriate, or if asked, but we have to preface it: "Instant wind 020 10kts" to make it clear to the crews which wind they're hearing.
Gonzo.
We can give the instant wind if we think it appropriate, or if asked, but we have to preface it: "Instant wind 020 10kts" to make it clear to the crews which wind they're hearing.
Gonzo.
aceatco, retired
Joined: Sep 2002
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From: one airshow or another
An instantaneous wind is just that, the wind at that instant. As Gonzo said, we usually use the 2 min average unless sepcifically asked for an instantaneous reading. We use a 10 min average for the METAR report, which goes out on the ATIS.
A gust is defined by the Met. Office as a maximum wind speed over the corresponding 10 mins which exceeds the mean by 10 kts or more. Don't think I've seen a definition (in the UK) of a peak wind
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VA
www.stevelevien.com
A gust is defined by the Met. Office as a maximum wind speed over the corresponding 10 mins which exceeds the mean by 10 kts or more. Don't think I've seen a definition (in the UK) of a peak wind
----------------------
VA
www.stevelevien.com
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From: UK
Many years ago I used to operate into a northern UK airfield and I am convinced that the controller (who was also involved in management) used to pass wind checks appropriate to aircraft type. I recall one occasion in particular when, on announcing that I was diverting, the crosswind instaneously dropped to precisely the limiting speed for my type. Having landed virtually sideways on that occasion, I have often wondered the accuracy of his wind checks!
?
Joined: Feb 2003
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From: Oxford
I once requested a wind check on finals (I was pretty convinced the crosswind was beyond me) and got a series of instant winds, e.g.
Wind 060 at 18, 070 at 15, 060 at 18, 050 at 20
until short finals. These were presumably instant winds, and were very useful (i.e. I promptly went around and asked for a different runway!).
Tim
Wind 060 at 18, 070 at 15, 060 at 18, 050 at 20
until short finals. These were presumably instant winds, and were very useful (i.e. I promptly went around and asked for a different runway!).
Tim
when passing wind, I always try to relax my cheek muscles, I find this gives the best results. 
aceatco, retired
Joined: Sep 2002
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From: one airshow or another
Eyes
If your local flying club is at an airfield will full ATC then they are required to comply with CAP670 ATS Requirements. This in turn, with wind instruments, requires compliance with ICAO Annex 3 Meteorology if there are 'schedule journeys' by aircraft over 5,700 kgs although I think it is set to apply to all aerodromes with ATC soon. I assume Annex 3 mentions the two minute average.
Pause for breath.
If your airfield is FISO then they are recommend to comply with CAP670. If A/G then not. You might find that many do anyway, the only way to find out is to go and ask.
For the terminally bored, the reference is CAP670 ATC01 Annex A.
VA
If your local flying club is at an airfield will full ATC then they are required to comply with CAP670 ATS Requirements. This in turn, with wind instruments, requires compliance with ICAO Annex 3 Meteorology if there are 'schedule journeys' by aircraft over 5,700 kgs although I think it is set to apply to all aerodromes with ATC soon. I assume Annex 3 mentions the two minute average.
Pause for breath.
If your airfield is FISO then they are recommend to comply with CAP670. If A/G then not. You might find that many do anyway, the only way to find out is to go and ask.
For the terminally bored, the reference is CAP670 ATC01 Annex A.
VA
Thread Starter
Joined: Mar 2000
Posts: 829
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From: You live where
thanks so far, I thought I'd go for a cheeky title (pun intended) go coax some responses and with 274 looks so far, not a bad return.
Vintage, I'm interested in the 10 minute average that you use for the Metar, I gather your equipment does this for you, am I correct?
And how does a pilot know that I am giving a 2 minute average wind? Is this buried deep within an ICAO doc somewhere?
Vintage, I'm interested in the 10 minute average that you use for the Metar, I gather your equipment does this for you, am I correct?
And how does a pilot know that I am giving a 2 minute average wind? Is this buried deep within an ICAO doc somewhere?
aceatco, retired
Joined: Sep 2002
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From: one airshow or another
Vintage, I'm interested in the 10 minute average that you use for the Metar, I gather your equipment does this for you, am I correct?
The use of the 10 min and 2 min average is an ICAO SARP and contained in Annex 3, para 4.5.5.
VA
Joined: Feb 2000
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In a past life when I was errr 'younger' and based at a very northern UK airfield,
Wind gusting over 70Kt, at the start of an ACR430 half-mile SRA,
“Eight miles, check wheels, surface wind 300 56kt gusting 74kt, I will continue to pass wind though out the approach” !!!
Wind gusting over 70Kt, at the start of an ACR430 half-mile SRA,
“Eight miles, check wheels, surface wind 300 56kt gusting 74kt, I will continue to pass wind though out the approach” !!!
Joined: May 2001
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From: Spanish Riviera
........ and how many of us altered the beam elevation in a vain attempt to get rid of conflictors?
We could always wax lyrical about how we "progressed" onto the AR1, but then that would be another story................
We could always wax lyrical about how we "progressed" onto the AR1, but then that would be another story................
Joined: Jun 2001
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From: southampton,hampshire,england
ACR 430
G-A , I hope you didn't operate the 430 outside the max wind limit, or maybe you had protection. The older 424 used to do funny things in high wind and I wouldn't dare use even a 430 to provide a serious SRA with that wind. I award you the Air Traffic Hero Medal for one week only, after which it will be re-assigned.
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Missy
In them days it was two dial's direction and instant wind speed readout, you had to remember the gusts and guess the average!
055166k
Ooooow always protected, we are talking Sumburgh here so if it wasn’t protected it wouldn’t have been there very long! Record when I was there was 93kt gusts with sustained over 70kt! I think the 430 was given to Albania for further use after the ILS went in.
In them days it was two dial's direction and instant wind speed readout, you had to remember the gusts and guess the average!
055166k
Ooooow always protected, we are talking Sumburgh here so if it wasn’t protected it wouldn’t have been there very long! Record when I was there was 93kt gusts with sustained over 70kt! I think the 430 was given to Albania for further use after the ILS went in.
