Airworthiness Directive


  • Airworthiness Directives (ADs) are legally enforceable regulations issued by the FAA in accordance with 14 CFR part 39 to correct an unsafe condition in a product
  • Part 39 defines a product as an aircraft, engine, propeller, or appliance

Types of Airworthiness Directives:

  • The FAA issues three types of ADs depending on the urgency of a condition
    • Notice of Proposed Rulemaking (NPRM), followed by a Final Rule
    • Final Rule; Request for Comments
    • Emergency ADs:

      • The FAA will issue an Emergency AD when an unsafe condition exists that requires immediate action by an owner/operator
      • Detailed information can be found on the FAA's Emergency Airworthiness Directives page

Issuance of Airworthiness Directives:

  • The FAA will issue airworthiness directives when they've determined a product meets two criteria:
    • An unsafe condition exists in a product; and,
    • The condition is likely to exist or develop in other products of the same type design
  • These directives are published in the Federal Registrar and FAA Regulatory and Guidance Library (RGL)
    • ADs can be found online through manual searches or by signing up for an email subscription
    • Both sources will list ADs by aircraft and engine makes and models selected
  • Airworthiness Directives may also have intervals:
    • One-time AD: requires a one-time modification
    • Recurring AD: requires a check or service to be performed on an ongoing basis at specific intervals
    • N/A AD: a "not applicable AD," but is still noted to show awareness of its existence

Airworthiness Directive Compliance:

  • All ADs are mandatory
  • An aircraft cannot overfly an AD
  • Usually require an inspection or conditions and limitations you must comply with
  • Operations specifications give some operators authority to operate including a provision that allow them to fly their aircraft to a destination to do that work

Special Flight Permit:

  • Must submit a statement in a form indicating:
    • The purpose of the flight
    • The proposed itinerary
    • The crew required to operate the aircraft and its equipment
    • The ways, if any, in which the aircraft does not comply with the AD
    • Any restrictions the applicant considers necessary
    • Any other information


  • Remember the owner or operator is responsible for airworthiness