Date of Award

January 2022

Document Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Daniel (Kwasi) Adjekum


A concurrent-embedded mixed-method triangulation design evaluated observed safety outcomes at a U.S. 14 Code of Federal Regulation (CFR) Part 121 air carrier. A previously validated model that measures Safety Management Systems (SMS process engagement and SMS policy implementation), transformational safety leadership, self-efficacy, safety motivation (mediator), and safety behaviors (safety compliance and safety participation) was assessed using structural equation modeling/path analysis. Semi-structured interviews of SMS subject-matter experts and safety leaders were used to explore the impact of SMS implementation. Factual data from the carrier was examined to provide convergent or divergent information regarding the other portions of the study. The results indicated SMS policy implementation had a significant effect on safety compliance (SC) and safety participation (SP), but SMS process engagement impacted only safety compliance (SC). A moderate relationship was found between safety motivation and both SC and SP. The results also indicated a significant effect of transformational safety leadership on safety motivation and SP. Self-efficacy and SC were weakly related. The results point to the importance of transformational leadership, clear safety policy, and motivation on safety outcomes. Gender differences were noted in SC and safety-related events, while years at the carrier were impactful on SC. Role at the company impacted safety-related event scores. Practitioners might consider tailored training due to the differences noted in this study. Future research is required to explore the impact of experience, role, and gender on safety outcomes and safety-related events estimation.