Reliability Program
Section 12: Continued Airworthiness & Maintenance
Definition
A data-driven program that monitors the in-service performance of aircraft systems and components to detect adverse trends, identify reliability issues, and provide a basis for adjusting maintenance tasks and intervals. The reliability program collects and analyzes data on component removals, failures, delays, cancellations, pilot reports, and maintenance findings to assess whether the aircraft maintenance program remains effective.
Where This Shows Up
Reliability programs are required for operators of transport category aircraft under their approved maintenance program. The program establishes alert levels (statistical thresholds) for key reliability metrics such as mean time between failures (MTBF), unscheduled removal rate, and in-flight shutdown rate. When a metric exceeds its alert level, the reliability program triggers an investigation and corrective action process. Corrective actions may include issuing service bulletins, revising maintenance procedures, adjusting inspection intervals, or implementing design changes. The reliability program is also the mechanism for requesting escalation (extension) of scheduled maintenance intervals when data demonstrates that the existing intervals are conservative.
Primary Sources
Includes provisions for reliability-based maintenance program management and interval adjustment.
FAA requirement for a continuous analysis and surveillance system (CASS), which encompasses reliability monitoring.
Related Terms
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