An Alternative Means of Compliance (AMOC) grants special permission to use an alternate means to comply with an Airworthiness Directive (AD) according to (CARs) 605.84(4). You need to apply for this special permission, and the alternate means you choose must provide a similar level of safety as the part or procedures that are normally required by the Airworthiness Directive.
Every AMOC must include at least one alternative. You can choose an alternate means of compliance for:
- repairs or modifications, including installing parts that aren’t affected by the Airworthiness Directive
- inspection procedures or intervals
- maintenance procedures or intervals
- extended compliance deadlines
- specified operating procedures or limitations
Transport Canada issues 4 types of AMOC:
- specific AMOCs apply to a single applicant
- blanket AMOCs apply to more than one owner or operator of any Canadian-registered aeronautical products
- global AMOCs apply to the same type of aeronautical product
- equivalent AMOCs letters are issued to applicants who submits a proposal that relates to:
- an Airworthiness Directive (AD) issued by a foreign Civil Aviation Authority, or
- a Canadian Airworthiness Directive (AD) that’s being used by a foreign Civil Aviation Authority that doesn’t recognize or accept Canadian AMOCs
A ministerial exemption under subsection 605.84(3) of the CARs grants special permission to the owner of a Canadian aircraft to act outside the normal requirements to comply with all or part of an Airworthiness Directive. You need to apply for this special permission and demonstrate that:
- under circumstances specified in the exemption request, compliance is impractical or unnecessary
- the exemption will provide a similar level of safety required by the Airworthiness Directive