| Airworthiness Directive (AD) |
Mandatory fix for unsafe conditions. |
EASA / State of Design |
High – strict deadlines |
| Service Bulletin (SB) |
OEM recommended improvements. Optional unless mandated. |
Manufacturer / OEM |
Medium – aligned with scheduled checks |
| Maintenance Program (AMP) |
Scheduled repetitive tasks per aircraft type. |
Type Certificate Holder / CAMO |
Continuous – based on FH, FC, or calendar |
| Defect Log / Tech Log |
Reports from crew or maintenance on discrepancies. |
Pilots / Mechanics |
High – MEL/CDL timelines apply |
| MEL / CDL Items |
Deferred items allowed under MEL/CDL limits. |
MEL Manual / EASA |
High – categorized timelines |
| Component Tracking |
Log changes: part #, install/removal, SNs. |
Tech Crew / System Input |
Medium – update after action |
| LLP Tracking |
Critical parts with flight-hour or cycle limits. |
OEM / Tracking System |
High – mandatory tracking |
| CRS (Release to Service) |
Signed statement confirming maintenance completion. |
Licensed Engineers |
Immediate – post task |
| ARC Docs |
Documents needed for annual airworthiness review. |
CAMO / Review Staff |
Annually |
| New Aircraft Delivery Setup |
System integration of new aircraft (AD/SB/AMP filtered). |
OEM / Delivery Team |
Once – before entry into service |