Airworthiness directive compliance
An Airworthiness Directive (AD) makes a maintenance or operation action mandatory, keeping an aeronautical product safe and conforming to its type design (CAR 101.01(1)).
- Issued by: the Minister, or the foreign authority responsible for the product's type design (
CAR 101.01(1)). - Is: a Transport Canada notice of a safety defect to rectify immediately, within a specified time period, or within a flight time limitation (
TP 1102).
Who it binds (CAR 605.84(1)):
- Every Canadian-registered aircraft, engine, propeller, appliance, or part with a design approval document.
- Exception: aircraft flown under a special certificate of airworthiness in the owner-maintenance or amateur-built classification.
Aircraft must also meet (CAR 605.84(1)):
| Requirement | Detail | Cite |
|---|---|---|
| Maintain to any airworthiness limitations applicable to the type design | Separate category from ADs (e.g. life-limited parts, certification maintenance requirements, structural inspection documents) | CAR 605.84(1)(a) |
| Meet any foreign notices equivalent to ADs | Issued by the foreign type-certificating authority, or the state of manufacture if no type certificate | CAR 605.84(1)(c) |
- Conflict with foreign notice: Canadian AD prevails (
CAR 605.84(2),Standard 625.84(iv)).
Owner's job (TC AIM LRA 5.7.1, Standard 625 Appendix B General Procedures note (i)):
- Do not fly unless the aircraft meets every applicable AD.
- Advise the AME of any outstanding AD before an inspection.
- Advise even by striking AD references off a manufacturer's checklist, so the AME is not misled into thinking it covers them.
Non-compliance (TC AIM LRA 5.7.1): outstanding AD means flight authority not in effect and aircraft not airworthy, even with a current Certificate of Airworthiness.
Routes around an AD (Minister grants only on a stated safety test, CAR 605.84):
| Route | Minister must grant if | Cite |
|---|---|---|
| Exemption | Owner shows BOTH: compliance is impractical or unnecessary in the circumstances, AND the exemption gives equivalent safety | CAR 605.84(3) |
| Alternative means | Satisfied it maintains the level of safety the AD's compliance time, modification, restriction, replacement, inspection, or procedure was meant to provide | CAR 605.84(4) |
Trap: impractical compliance alone does not earn an exemption; equivalent safety must also be shown. Likewise an unexpired C of A on board does not make the aircraft airworthy; one overdue AD ends the flight authority the moment the compliance deadline passes.
References
- CAR 101.01(1), CAR 605.84, Standard 625.84, Standard 625 Appendix B General Procedures, TC AIM LRA 5.7.1
- TP 1102, Aircraft Documentation: Certificate of Airworthiness