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An AD mandates actions to be performed to restore an acceptable level of safety to an aircraft, when evidence shows that the safety level may otherwise be compromised.
Canadian ADs are issued by the Minister pursuant to the conditions prescribed in Canadian Aviation Regulation, Part V, Subpart 93 (CAR 593). Pursuant to CAR Part VI, Subpart 5, section 84 (CAR 605.84) and the further details of CAR Standards (Airworthiness Manual) 593 and 625, the continuing airworthiness of a Canadian aircraft is contingent upon compliance with all applicable ADs. Failure to comply with the requirements of an AD causes the certificate of airworthiness of the aircraft to be out of force. Applications for an alternative means of compliance with the requirements of an AD must be made in accordance with CAR Standard 625, Appendix H.
An Airworthiness Directive contains, at a minimum, the following information:
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No person may operate an aircraft to which an AD applies, except in accordance with the requirements of that AD, unless otherwise agreed with the Civil Aviation Authority of the State of Registry.
Distribution:
The ADs applicable to an aircraft are those issued or adopted by the State of Registry of this aircraft.