Authorities issue ADs under their legal framework. Compliance is determined from the exact AD revision, product applicability, aircraft or component status and approved records.
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AIRWORTHINESSBEGINNERREVIEWED Aug 2026
AD
AD Abbreviation · Airworthiness Directive Synonym
Airworthiness Directive: a legally enforceable requirement addressing an unsafe condition.
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How the term is used
An AD defines applicability, required actions, compliance time and any approved alternatives or terminating actions. It may require inspection, modification, replacement, operational limitations or repetitive action.
Where you may encounter it
Maintenance and continuing-airworthiness teams use AD status records to plan, accomplish and prove compliance.
A service bulletin does not automatically replace an AD. Use the current authority publication and approved compliance instructions.