Airbus Alert Height - What is it?
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@ cdc1172
ATIS
Off topic indeed but, as it has become very silent here for the moment, I give you an answer in here anyway. I think maybe a moderator will be so kind to put it in an other place later…
Before an aircraft departs from or arrives at an airport the crew usually listens to an Automatic Terminal Information Service. Specific information, (runway in use, weather, operational info, etc.) necessary for the crew on board to know, is automatically and continuously broadcasted on a VHF frequency in the air communication band and/or through the frequency of a navigation ground beacon.
The spoken message is either dictated on a tape by a human or created by a computer-generated voice. The message comes in a standard specific format, well known to pilots.
From time to time the details of the information changes. (For example: runway in use, wind, temperature or the unservicebility of a navigation beacon) So an altered, updated message will be recorded and broadcasted. All messages will be given a different letter code to identify the message. After message A, the next updated message will be message B. When updated again, message C will be broadcasted and so on… The whole alphabet is used.
Now, what you are talking about hearing around you all the time, is that pilots say to the tower or radar that they have “received information BRAVO…!” (Message B…) so that the controller can confirm (He woud reply:"Information BRAVO corect...!") that the crew has received and thus has knowledge of the latest and correct information.
Or that the controller says: “Information CHARLIE (Message C…) is now current…!” so that the crew can verify the “ATIS” again if they had just listened to the previous information BRAVO (and thus the ‘old’ information, that is no longer current…)
Example of an ATIS message:
“This is Luton information TANGO, time 06:20;
airport/operational information, locator LTN out of service;
runway in use 23; runway damp, damp, wet; braking action, good, good, medium to good;
wind 290 degrees 16 knots gusts 26 knots;
haze; visibility 3000 meters;
clouds broken at 800 feet, overcast at 1200 feet;
temperature minus 3 degrees, dew point minus 8 degrees;
QNH (pressure) 1008 millibars;
on first contact advice ATC that you have received information TANGO…”
Kind regards, learner . . .
ATIS
Off topic indeed but, as it has become very silent here for the moment, I give you an answer in here anyway. I think maybe a moderator will be so kind to put it in an other place later…
Before an aircraft departs from or arrives at an airport the crew usually listens to an Automatic Terminal Information Service. Specific information, (runway in use, weather, operational info, etc.) necessary for the crew on board to know, is automatically and continuously broadcasted on a VHF frequency in the air communication band and/or through the frequency of a navigation ground beacon.
The spoken message is either dictated on a tape by a human or created by a computer-generated voice. The message comes in a standard specific format, well known to pilots.
From time to time the details of the information changes. (For example: runway in use, wind, temperature or the unservicebility of a navigation beacon) So an altered, updated message will be recorded and broadcasted. All messages will be given a different letter code to identify the message. After message A, the next updated message will be message B. When updated again, message C will be broadcasted and so on… The whole alphabet is used.
Now, what you are talking about hearing around you all the time, is that pilots say to the tower or radar that they have “received information BRAVO…!” (Message B…) so that the controller can confirm (He woud reply:"Information BRAVO corect...!") that the crew has received and thus has knowledge of the latest and correct information.
Or that the controller says: “Information CHARLIE (Message C…) is now current…!” so that the crew can verify the “ATIS” again if they had just listened to the previous information BRAVO (and thus the ‘old’ information, that is no longer current…)
Example of an ATIS message:
“This is Luton information TANGO, time 06:20;
airport/operational information, locator LTN out of service;
runway in use 23; runway damp, damp, wet; braking action, good, good, medium to good;
wind 290 degrees 16 knots gusts 26 knots;
haze; visibility 3000 meters;
clouds broken at 800 feet, overcast at 1200 feet;
temperature minus 3 degrees, dew point minus 8 degrees;
QNH (pressure) 1008 millibars;
on first contact advice ATC that you have received information TANGO…”
Kind regards, learner . . .
Join Date: Nov 2000
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You either have a Decision Height (DH) for Cat 3a or 3b, or you have an Alert Height (AH)for Cat 3c: you can't have both in so much as Cat 3C is a no DH approach (nominally 15ft or the like).
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Thats right.
NO DH, ergo an Alert Height.
If you have a DH of 50ft you don't have an Alert Height as you are operating to Cat 3a.
Cokeman, I stand corrected Cat3C has been removed from EU Ops. It now lists only 3a, DH less than 100ft and 200m and 3b, less than 50ft, or no DH, and 75m with fail operational system, which is where Alert Height comes in.
NO DH, ergo an Alert Height.
If you have a DH of 50ft you don't have an Alert Height as you are operating to Cat 3a.
Cokeman, I stand corrected Cat3C has been removed from EU Ops. It now lists only 3a, DH less than 100ft and 200m and 3b, less than 50ft, or no DH, and 75m with fail operational system, which is where Alert Height comes in.
