Analysis of SSN 688 Class Submarine Maintenance Delays

Abstract

The combination of negative real budget growth and unchanged operational use has stressed the resources of the United States Navy, resulting in an annual average over-budget execution of $0.77 billion per year in Navy-wide ship depot maintenance since FY2010. The Navy's active ship maintenance budget only supports 70 percent of the ship maintenance projected in FY2017; a significant portion of over-budget execution and delays has occurred with submarine availabilities. Delays to a submarine's return to the fleet results in a decrease of the overall operational availability (Ao) of already diminishing submarine force levels. In this thesis, data collected from Pearl Harbor Naval Shipyard (PHNSY) is analyzed to investigate possible factors impacting the ability of maintenance activities to complete SSN 688-class submarine maintenance availabilities as scheduled. The analysis illustrates a systematic underestimation of availability duration due to the use of outdated historically based estimates following a significant shift in maintenance strategy in 2012. Additionally, the analysis shows a significant increasing trend in the average number of man-days required to complete a job. This thesis provides a narrowed focus for future studies attempting to determine the cause of this trend. Finally, this thesis proposes a solution to the systematic underestimation of availability durations by illustrating the inherent error in the current equation and providing a notional equation to remove that error.