Maintenance Practices, Inspection and Airworthiness for Aeroplanes
Rules and records
In New Zealand, Part 43 governs aircraft maintenance, Part 66 licensing, Part 91 operations and Part 39 airworthiness directives. An AD is mandatory: record the method, date and hours or cycles of compliance and the next due point. Service bulletins are not automatically mandatory, only when an AD, the maintenance programme or the operator's requirements make them so. Certification of maintenance must be made by a person with the correct rating and scope, and a maintenance release is required where the operating rules demand it.
Inspection practice
Use calibrated equipment and record its calibration. Critical tasks such as flight control connections, engine assembly and pressurisation work require an independent or dual inspection. Defects are either rectified or deferred under an approved MEL or deferral, and both must be recorded. Occurrence and service difficulty reporting feed back into continuing airworthiness.
Worked example
An AD calls for a repetitive inspection every 100 hours TIS. It was last done at 1,240 hours and the aircraft is now at 1,318 hours. The next due point is 1,340 hours, so the planned 6-hour flight is acceptable, but the due point must be recorded and the next inspection scheduled. At 1,345 hours the aircraft would be unairworthy for that flight without an approved alternative.
Traps
Assuming all service bulletins are mandatory; certifying outside your rating; using an out-of-calibration torque wrench; failing to record AD compliance; treating a deferred defect as closed.