Airworthiness, Maintenance Practices and Documentation
Domain focus: This section covers airworthiness and maintenance practice: approved data, inspections, documentation and the release of an engine to service under PNG CASA requirements.
Maintenance practice
- Maintenance must follow approved data: the aircraft maintenance manual, component maintenance manual, service bulletins and airworthiness directives. ADs are mandatory; service bulletins are mandatory only when incorporated by an AD or contract.
- Inspections include borescope, NDT, oil analysis, filter checks, performance trend monitoring and dimensional checks. Parts must be traceable, tagged and approved for the engine type.
- Documentation includes task cards, work orders, logbook entries, defect reports, certificates of release to service and maintenance records. Certifying staff must record what was done, by whom, with what data and what result.
Worked example
A borescope finds a nick on a compressor blade. The manual gives a blend limit and a re-inspection interval. The technician blends the blade within the limit, records the before/after dimensions, references the manual section, and certifying staff sign the release. The reasoning: a blade within limits may be returned to service; damage beyond limits requires blade replacement. Traceability matters because an unrecorded blend cannot be audited later.
Traps
Do not treat all service bulletins as mandatory; do not fit an unapproved part because it looks identical; do not sign for work you did not inspect; do not omit the reference to approved data; do not rely on memory for torque values or limits.