Alternative methods of compliance
6.1 An Alternative Method of Compliance (AMOC) is a different approach or technique not specified in an AD/MPD that can assure a level of safety equivalent to that offered by direct compliance with the subject AD/MPD.
6.2 AMOC’s may be issued in respect of, but not necessarily limited to alternative:
a) Design changes (modifications);
b) Inspection procedures and/or maintenance intervals;
c) Changes to specified operating procedures or limitations.
6.3 A request for a timescale change (i.e. extension) to an AD/MPD is not a candidate for an AMOC. A timescale change, if agreed, should be approved by the issue of an exemption to the AN(OT)O for the non-compliance with the AD/MPD. When approved, an AMOC should not have a specified period of validity since it has been accepted as an equivalent safety case to an existing AD/MPD. AMOCs are not considered a routine approach to compliance with mandatory airworthiness requirements. Compliance with the AD/MPD is often the simplest and most direct method of addressing the airworthiness concern.
6.4 The preferred acceptance of an AMOC, by an OTAA, is to utilise an already existing AMOC approved by the State of Design or State of Certification that issued the original AD/MPD. Applicants will be requested to comply with this existing AMOC. The suitability of any existing AMOC may require assessment using engineering assistance and/or TC/STC/TA support. An example of a possible alternative AMOC would be one where the aircraft serial number applicability on the AD/MPD is different from that of the subject aircraft which would require further investigation as to its suitability.
6.5 If a suitable AMOC does not already exist, the application, to an OTAA, for an AMOC must be from the TC/STC Holder or have the support of the TC/STC Holder, or Type Approval Holder for a Permit Aircraft.
6.6 The OTAA will review the content of any proposed AMOC application and determine whether an equivalent level of safety to the original AD/MPD has been demonstrated. The OTAA will advise the applicant in writing if the AMOC is acceptable on the Territory aircraft.