HSI in the USN frigate community operational readiness and safety as a function of manning levels

Abstract

Human Systems Integration (HSI) is a process designed to reduce life-cycle costs and improve system performance by considering human-related domains. Acquisition specialists lack objective, quantitative research findings on which to base trade-off analyses. This thesis used eight fiscal years of historical safety (mishaps), manpower (manning levels) and system performance (SORTS) data on the U.S. Navy's Frigates, collected from computer databases of routine reports, to explore relationships in an existing notional model of HSI. Three hypotheses were tested: there is a negative relationship between manning and SORTS levels; there is a negative relationship between manning and mishaps; and there is a positive relationship between mishaps and SORTS levels. No significant relationships were found between SORTS levels and manning or mishaps. When all of the ships were ranked for each month based on percent of total manning and number of reportable mishaps, a positive correlation (Spearman's rho = 0.4194, p-value = 0.0294) was found corresponding to a negative relationship between manning levels and mishap rates. More detailed research is needed to isolate the relationship between manning levels and mishap rates from numerous other influences and any noise that may be present in the data set.