OBJECTIVE

WORK SCOPE Reliability Centered Maintenance Analysis (RCMA) is a vehicle for maintenance planning, the purpose of which is to develop a scheduled maintenance program that includes only those tasks to preserve safety and operating reliability, economically. The concept requires that after the program has been placed in operation, it shall be monitored continually over the life of the aircraft through an organized information system. Management attention is necessary to confirm, through operational experience.
Mil-Std-1843 or 2173 ???
Both standards address the same objective; a cost effective Maintenance Program. Mil-Std-1843 (USAF) has been cancelled without replacement on August 9, 1995.
Mil-Std-1843 (USAF) has a lot of ambiguity. The definition of SSI (Pg. 7 paragraph 3.1.59) tends to be misleading. It includes "structural detail" and this can lead to the interpretation that details like fastener holes, fillets, etc. are SSI rather than details whose failure contributes to the overall failure rate of the part they are on.
KT-1 RCMA utilizes Failure Mode Effect Criticality Analysis (FMECA) IAW Mil-Std-1629. The FMECA documents the component item's function, functional failure and failure mode(s) and the effect(s) at local, next higher, end item levels. The criticality of the end effect is what determines the criticality of the item under analysis.
ADD provided their Structural Significant Items (SSI) list based on their Durability and Fatigue Analysis. SSI selection was not performed in the normal sequence since it would have resulted in redundant efforts, but in the process of other analysis steps, items deemed significant (with the approval of analyst’s ADD counterpart) were added to the SSI list.

Normal analysis sequence is: 1. Structure Item Identification (SII / Part I of the RCMA); 2. FMECA; 3. ED and AD Analysis (Part II of the RCMA); 4. Inspection Task Identification: 5. Initial Inspection and repeat interval.

Introduction	Work Scope	SSI Selection	F M E C A	M T B F	Figure 1	RCMA Pt 1
Item Data	RCMA Pt 2	Answers	Inspections	Age Exploration	F S M P	Follow Up