Leadership in Engineering Systems Engineering Program Department of Engineering Management, Information and Systems EMIS 7305/5305 Systems Reliability, Supportability and Availability Analysis Reliability Centered Maintenance (RCM) Analysis Dr. Jerrell T. Stracener, SAE Fellow Leadership in Engineering

Introduction RCMA is a disciplined approach to determine systems Preventive Maintenance (PM) programs. Candidate items are selected for analysis as early as possible, and re-applied when needed. For each item, an attempt is made to identify potential failures that are correlated with usage or time passage. PM tasks may result, depending on criticality and feasibility. Calculated intervals for identified PM tasks are determined using the best-known life characteristics. Results are documented.

Sources of information Introduction Approach History of requirements documents Key Tenets Conclusions Sources of information WWW Military standards/handbooks Journal articles Experience

Commercial Documentation History MSC-1 (1968, by Boeing Maintenance Steering Group, to support 747 scheduled maintenance program) MSC-2 (1970, by (ATA) Air Transport Association (ATA) of America and task force of appropriate stakeholders, to support other A/C) Reliability-Centered Maintenance, Stan Nowlan and Howard Heap, 1978 MSG-3 (published by the ATA in 1980 to support more-complex A/C, like the 757/767, and address more-stringent FAA regulations and economic issues) Latest revision 2001. SAE JA1011 (1999) and JA1012 (2002) are “sister” specs

Military Documentation History Early efforts used commercial docs/reqts DA PAM 750-40 (USA 1980) MIK-HDBK-266 (DOD 1981) MIL-STD-1843 (USAF 1985 (cancelled 1995, no superseding doc.)) MIL-STD-2173 (USN 1986 (cancelled 1999)) MIL-STD-2173(AS) (USN 1998 (cancelled 1999)) NAVAIR-00-25-403 Late efforts tend to use commercial docs/reqts

Key Tenets “This process can only address maintenance preventable failures, i.e. it cannot defend against unlikely events, non-predictable acts of nature, etc. ” Wikipedia Candidates are identified early in a development using Failure Modes and Effects Analysis (FMEA). Each FMEA candidate is subjected to RCMA. An example of early Army RCM logic tree attached at end of this package. RCMA can be used with Failure Modes, Effects, and Criticality Analysis (FMECA) per MIL-STD-1629 to identify and assign criticality to potential failures.

Key Tenets (cont) Results are documented in some fashion. Existing tool In-house tool Logistics Support Analysis Record (LSAR) is a formal data documentation process that can be used to collect results of RCM logic application. See cancelled MIL-STD-1388-2B Tools developed per US MIL-STD-1388-2B or MoD 00-60 can be used rather than developing an in-house tool.

Key Tenets (cont) Application of RCMA may result in: Servicing Task Lubrication Task On-Condition (scheduled inspection) Task Hard-Time (scheduled removal) Task Failure-Finding (scheduled inspection of hidden function) Task No PM Task (if “No PM Task” is unacceptable, then redesign, operational restrictions, change in maint procedures, etc., may be necessary). Age Exploration In short, RCMA results in a PM task of some type, system redesign, or an item is allowed to fail.

Conclusions Generally applied to aircraft and power plant acquisitions. Generally not applied to US acquisitions that are not new significant systems. Applied more heavily to smaller acquisitions by UK, Australia, New Zealand, Korea, ROC RCMA is generally not applicable to electronic items. It applies to items that have increasing failure rate over time, or have inherent wear-out characteristics. In personal experience, it has not been rigorously applied to any small US system since approximately 1994.

References Websites Documents http://assist.daps.dla.mil/quicksearch http://logistics.navair.navy.mil/rcm/library http://www.mtain.com/logistics http://logistics.navair.navy.mil/rcm Wikipedia Documents MIL-STD-2173, MIL-STD-2173(AS) RCM (cancelled) NAVAIR-00-25-403 RCM MIL-STD-1388-2B LSAR MIL-STD-1629 FMECA Logistics Spectrum, Apr-Jun 2002, Richard W. Anderson

RCM Process Diagram Reference: NAV-00-25-403 (Navy)

RCM Logic Diagram Reference: DA PAM 750-40 (Army). Detailed use instructions are provided (1982).

Full RCM Program Task Sequence Flowchart

Full RCM Program Task Sequence Flowchart (cont)

Full RCM Program Task Sequence Flowchart (cont)

Full RCM Program Task Sequence Flowchart (cont) Collect test and in-service data STEP 28 Does new data support current FMECA and RCM entries? STEP 29 Go to STEP 6 F Implement PM tasks STEP 27 NO YES NAVAIR RCM website: http://logistics.navair.navy.mil/rcm/guidance.cfm.