A few years back, our particular airline had a particular type that had a particular noise abatement procedure used that was different from NADP1 or 2 when departing from a particular runway at a particular airport
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It was approved by the airport authority and had a different thrust reduction and flap operation height based on a DME distance. The strange thing was, when I happened to be talking to a tower controller at that airport, he was completely unaware of this procedure.