Programmed Depot Maintenance Capacity Assessment Tool

Aging U.S. Air Force fleets have deterioration problems, resulting in increased maintenance workloads. Nowhere are those increases more troubling than in the workloads associated with programmed depot maintenance (PDM), which can be significant, requiring 2,000 to 50,000 labor hours. RAND developed the PDM Capacity Assessment Tool (PDMCAT), applied it to the KC-135 PDM process, with three alternative forecasts of future workload and two fleet-size scenarios, to inform aircraft availability and resource allocation decisions. The PDMCAT forecasts the annual number of aircraft that will be in PDM status over several decades, based on the initial number of aircraft in work, the physical capacity of the facility, the PDM induction policy, and the minimum hands-on flow time. Because few facilities will share information about their individual processes, the PDMCAT uses direct observation to estimate aircraft time in maintenance, such as number of docks for conducting maintenance and recent measures of actual performance. Using historical workload status, PDMCAT accurately reflected the increase and subsequent decrease in the number of aircraft in PDM status (i.e., maintenance), and it identified an alternative aircraft induction interval plan to bring the surge in aircraft-in-work back to acceptable levels through 2009. The model would mainly be used to support fleet PDM planning, programming, and budgeting, and to support facility and process improvement.