Streamlined RCM and LRCM

There is not a huge difference between the various flavors of the process of RCM (for example SRCM, JA-1011, Turbo RCM, and many others). The differences are mostly in terminology and details rather than in the actual concepts. The SAE JA-1011 minimum requirements for RCM provide the simplest, quickest, and at the same time the most rigorous RCM process. Most of the world’s armed forces, after considerable trial and error over the past 30 years, today base their own RCM standards on SAE JA-1011. Civil and commercial, aviation is by far the most reliable industry in the world. They use a process, called “MSG-3”, that conforms closely to the SAE JA-1011 standard. They have done so for 35 years.

JA-1011 actually defines the minimum requirements for RCM. It says that RCM must at the very least answer the seven questions:

1. What are the item’s functions to be conserved? (The performance requirement)
2. In what ways can these functions be compromised? (The failure or failed state)
3. What causes the loss of function? (The failure mode)
4. What happens? (The effects)
5. How does it matter? (The consequences)?
6. What maintenance task should be done to avoid or lessen the consequences?
7. What if no appropriate maintenance task can be found?

Most of the RCM processes answer the questions, some not as clearly as JA-1011. Question 4 describes “the effects”. The effects recount the “story” about what happens and could happen when the failure mode occurs. By completing the Effects text in the way suggested by the JA-1011 standard, we  easily determine the consequences. Dealing appropriately with the failure consequences is the entire reason for performing RCM. Most other RCM processes do not elicit the answer to Question 4 as thoroughly as the JA-1011 standard requires.

The LRCM process complies with JA-1011. However, additionally, it solves a major shortcoming of RCM. Up until the advent of LRCM there had been no rigorous, systematic, practical procedure to improve RCM knowledge in a natural continuing process. Initial RCM knowledge is developed in RCM projects. The “initial” RCM knowledge base is based on the best approximations, assumptions, and recollections available to the analysts at the time. The RCM analysis, at the end of an RCM project, is converted to a maintenance plan and inserted in the maintenance system. Thereafter, little systematic updating  of the initial analysis, in the light of new experience, takes place.

With LRCM, each significant work order provides the maintenance organization with the natural and convenient opportunity to sanity check the approximations in the initial RCM analysis. It is easy at that point to update the knowledge because the work order is fresh in the minds of all concerned. LRCM links the work order system with the RCM knowledge base. LRCM software processes work orders as instances of RCM knowledge records converting them into samples for analysis. The link between work orders and the RCM knowledge base enables “Reliability Analysis” (RA), RA is the precursor to tangible maintenance improvement.

© 2011, Murray Wiseman. All rights reserved.