The current USAF process for establishing intervals between C-130 PDM does not account for the wide range of aircraft variables within each aircraft MDS. This paper develops an analytical model, based on five unique aircraft variables, to provide C-130 maintainers with a prediction tool to forecast when a C-130 aircraft requires PDM. These five variables include: aircraft age, total flying hours, average yearly flying hours, mission profile (expressed as a severity factor), and operating location of the aircraft. Interviews with C-130 SPO personnel, combined with use of the C-130 Service Life Data Base, provided the required data to develop the C-130 PDM interval model.The C-130 PDM interval model developed in this paper allows maintainers and operators to predict the optimum time between C-130 PDM activities. It eliminates the requirement to base PDM intervals on aircraft MDS. As a result, there is a potential for significant savings by deferring PDM for a portion of the C-130 fleet. Finally, the PDM interval model developed in this paper may be applicable for other DOD aircraft which use aircraft MDS as the determinant of PDM intervals.