Dyna-METRIC Extensions: Partially Mission Capable Due to Supply.

Dyna-METRIC models repairable aircraft parts and assumes that the failure of any part would cause the aircraft to be Not Mission Capable due to Supply (NMCS). That assumption is relaxed in this paper to allow parts to be classified as essential, those whose failure would cause the aircraft to be NMCS, and nonessential, those whose failure would cause an aircraft to be Partially Mission Capable due to Supply (PMCS). Formulas are developed for computing the expected number of aircraft NMCS, PMCS, or both at any time for each of two maintenance policies. The first policy does not allow good parts to be removed from an aircraft, whereas the second does. Also, the results for two sets of parts are extended to allow the nonessential class to be further divided. (Author)