AC 43.9C:
12. LOST OR DESTROYED RECORDS. Occasionally, the records for an aircraft are lost or destroyed. In order to reconstruct them, it is necessary to establish the total time in service of the airframe. This can be done by reference to other records that reflect the time in service; research of records maintained by repair facilities; and reference to records maintained by individual mechanics, etc. When these things have been done and the record is still incomplete, the owner/operator may make a notarized statement in the new record describing the loss and establishing the time in service based on the research and the best estimate of time in service.
a. The current status of applicable ADs may present a more formidable problem. This may require a detailed inspection by maintenance personnel to establish that the applicable ADs have been complied with. It can readily be seen that this could entail considerable time, expense, and in some instances, might require the AD being performed again to establish compliance.
b. Other items required by § 91.417(a)(2), such as the current status of life-limited parts, time since last overhaul, current inspection status, and current list of major alterations, may present difficult problems. Some items may be easier to reestablish than others, but all are problems. Losing maintenance records can be troublesome, costly, and time consuming. Safekeeping of the records is an integral part of a good recordkeeping system.