Noise Abatement Departures Procedure [NADP 1, NADP 2, ICAO A, ICAO B]. 

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The Noise Abatement Procedures are procedures that you need to follow in order to comply with the noise restrictions of your departure airport.
There are 4 Noise Abatement Procedures:
NADP 1
NADP 2
ICAO A
ICAO B
You can find which Noise Abatement Procedure is applicable to you on the AOI or General Part of your airport charts.
The difference between these 4 Noise Abatement procedures is the Height at which you have to reduce the Power and the height at which you have to pitch down, accelerate, and retract the flaps on schedule.
It all depends if you have to make less noise possible in the short distance or the long distance.
It is very important to understand that Safety has priority over these Noise Abatement Procedures, so if you have a problem that affects your performance you disregard these procedures in the name of safety.
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Disclaimer:
THIS VIDEO IS FOR ENTERTAINMENT PURPOSES ONLY.
NOT FOR REAL-LIFE OPERATIONS.
PLEASE REFER TO THE OFFICIAL MANUAL AND DOCUMENTATION.
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