Air Transport Association "Subject Headers"

From: (Paul Makinen)
Organization: Express Access Online Communications, Greenbelt, MD USA
Date:         21 Jul 96 13:29:36 
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I have a document that refers to "ATA Headers":  For example, ATA 21
refers to Air Conditioning Systems, ATA 23 is Radio Equipment, ATA 32 is
Landing Gear, ATA 25 is Passenger Cabin, etc...

Does anyone know what document these are from?

All assistance appreciated...