Trend analysis of repair times

Results of applying the US Army Material Systems Analysis Activity (AMSAA) and Kalman filter (KF) models to repair time data are examined. Repair rates (the inverse of the mean time to repair, 1/MTTR), as equipment operation continues and maintenance procedures mature, can be successfully analyzed using either of these procedures. Instantaneous MTTR estimates are assessed from the model outputs, and future MTTRs are predicted based on the results of model fits. Both models corroborate the results found with each independently, however, the technical approach and interpretation of the results differ due to modeling reference frames