There has been a certain confusion about the understanding of “detailed maintenance records”, because this term is used in a different context for continuing airworthiness management and approved maintenance organisation (AMO).
“Detailed maintenance records” as defined in M.A.614 or 145.A.55(c) are required to be kept by an AMO (respectively Part-M/F organisation or Part-145 organisation). Maintenance organisations are required to retain all detailed records in order to be able to demonstrate that they maintained aircraft and components in compliance with applicable requirements (see also remark).
“Detailed maintenance records” as defined in M.A.305(h)(1) are those records, coming from the AMO1 having performed maintenance, required to be kept by the owner/operator (or the CAMO when required by M.A.201) allowing to determine the aircraft configuration, the airworthiness status of the aircraft and all components installed, as well as to plan future maintenance as required by the AMP, based on the last accomplishment.
Consequently, the AMO should transmit to the owner/operator/CAMO a certain subset of the AMO maintenance records, including the certificates of release to service and repair/modification data related to the performed maintenance, so that the owner/operator/CAMO can demonstrate compliance with M.A.305.
Not all AMO maintenance records need to be transferred from the AMO to the owner/operator unless they specifically contain information relevant to aircraft configuration/ status and future maintenance. Thus, incoming certificates of conformity, batch number references and individual task card sign-offs verified by and/or generated by the maintenance organisation are not required to be transferred to the owner/operator/CAMO. However, dimensional information contained in the task card sign-offs or work packages may need to be transferred and kept by the owner/ operator.
It is to be noted that the record-retention period requirements are slightly different for the AMO and the CAMO. The AMO shall retain the records for 3 years, whereas the CAMO has to retain their records until they are superseded by new information (equivalent in scope and detail), but not less than 3 years. The starting point in both cases is when the aircraft or component maintenance has been released.
Remark: It is considered a best practice as part of the AMO record-keeping system, (and it is also required by certain competent authorities) to record information (e.g. batch number or other tracking reference) relevant to the identification of all standard parts and material used during any maintenance. This practice may limit safety and industrial risks in the case where a batch is recalled by the manufacturer. Such record does not need to be transmitted to the owner/operator/CAMO.
*: Transmitted records is a subset of AMO maintenance records provided to the CAMO. Certain transmitted records do not need to be kept as a record by the CAMO such as EASA Form 1 for a component with no scheduled maintenance task selected and not subject to AD or modification/repair.
**: by new information equivalent in scope and detail
1 Or pilot-owner [M.A.803], or independent certifying staff [M.A.801(b)(2)]