SRC Forum - Message Replies
Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and Answers
Topic Posted by: Reliability & Maintainability Forum
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Posted by: John Schweighardt
Date posted: Thu Jun 28 11:43:37 US/Eastern 2001
Subject: Spares Calculator
I have been using an old Lotus spares calculator (15 years), but it's been acting up lately. Is there a good, Windows-based software package available out there? I've been unsuccessful in my search.
Subject: Actuarial method for spares calculations
Reply Posted by: Larry George
Organization: Problem Solving Tools
Date Posted: Fri Jul 20 15:52:23 US/Eastern 2001
Please refer to http://members.home.net/pstlarry/PrRelAct.htm for software specification for actuarial forecasts. Actuarial forecasts are used by the US Air Material Command and airlines for service and spares planning for high cost, fracture critical parts like engines and major engine modules.
The software specification doesn't mention it, but I also estimate the distribution of forecast demand, for recommending stock levels. Using the real distribution obviates the need for the Poisson assumption in the Air Force actuarial method and the normal distribution assumption used elsewhere. Spreadsheet versions are available. Please request my article, "Forecasting for the Automotive Aftermarket," for more information.
Reliability statistics, http://members.home.net/pstlarry/ProdRel.htm, allow actuarial methods to be used for ALL parts, not just those tracked by serial number. If you like, send field data, and I will send back nonparametric estimates of age-specific field reliability and failure rate functions, actuarial forecasts, and their distributions, FREE.