Development of a downtime influence factor severity index for improvement of naval ship availability: A simple approach for the Malaysian patrol vessel in-service support contract

Navies worldwide have applied with a varied degree of success various maintenance concepts to achieve certain targeted operational ship availability. Nevertheless, few concepts focus on both the human and equipment factors that drive the unavailability or downtime. These factors can be designated as Downtime Influence Factors (DIFs). In previous research the severe DIFs had been identified via a 5-Stage Delphi conducted with experts in the field of Patrol Vessel (PV) In-Service Support (ISS) Contracts in Malaysia. By prioritizing and rating these DIFs based on Risk Assessment it was possible to determine a Severity Index formula. In a first step, the Severity Index (SI) prioritized the DIFs that are severe. In a subsequent step, the interrelationship of the DIFs was analyzed with the help of SPSS and the SI index was adjusted to take into account interrelationships. The resulting adjusted SI assists PV ISS contract stakeholders to pinpoint and focus on human and equipment factors that are the main causes of downtime.