Causal Factors Analysis of runway excursion occurrences through Fuzzy Logic Modeling method

Abstract

Runway excursion (RE) was one of main contributing factors to aviation occurrences whilst unstable approach precursors were the ones accounting for a significant proportion of those occurrences. The objective of this study is to identify the most influencing causal factors (hazards and risks) of RE occurrences and propose countermeasures to mitigate potential RE risks and RE occurrences in Taiwan. Causal Factors Analysis System and Fuzzy Logic Modeling method are used to classify hazards and risks of RE occurrences and establish a fuzzy logic model for RE occurrence predictions. The final squared multiple correlation coefficients (R² = 0.9999) verify that the predictive capabilities of the final RE model are not affected after the exclusion of the less influencing parameters. Sensitivity analysis reveals that avoiding crosswind or tailwind landings can significantly reduce the likelihood of RE occurrences; and reducing inadequate supervision related errors is the most cost-effective strategy to mitigate probable RE risks. Local civil aviation authority and airline operators are all responsible to collaborate with each other to mitigate causal factors of RE occurrences due to inadequate supervision. Recommended countermeasures to the civil aviation authority: maintain sufficient depth of technical staff and appropriate deployment of management level personnel to conduct safety oversight; to airline operators: formulate non-punitive policy, clearly define and document go-around procedures, and develop evidence-based training for pilot monitoring's competencies needed including monitoring, call out and intervention to take control.