Risk Assessment of the Coupled Air–Sea Environment in Bell 412 Helicopter Operations on Shipboard Decks: A Preventive Approach to Enhancing Operational Safety

Helicopter operations involving the Bell 412 on shipboard decks—particularly in dynamic maritime environments—are associated with significant safety risks stemming from the complex interaction between atmospheric and oceanic factors. This study aims to comprehensively assess the coupled air–sea environmental risk in Bell 412 shipboard operations and propose evidence-based, preventive strategies to mitigate offshore helicopter accidents. A hybrid methodology was employed, integrating historical accident analysis, expert surveys (32 qualified respondents including pilots, naval officers, and safety engineers), and high-fidelity coupled dynamic simulation (1,200 Monte Carlo scenarios) that concurrently models the Bell 412's flight dynamics and the ship's six-degree-of-freedom motions. Results reveal that operational risk is not governed by significant wave height alone, but by a nonlinear combination of deck heave acceleration, crosswind velocity, and wave peak period. Sensitivity analysis using Sobol indices showed that heave acceleration accounts for 41% and crosswind for 36% of the variance in failure probability. Critically, under current operational thresholds (e.g., significant wave height = 2.0 m), the probability of failure reaches 38%—a level deemed unacceptable for safe operations. Accordingly, this research proposes a Combined Sea–Air Safety Index and practical countermeasures, including real-time decision support systems, integrated ship–helicopter data fusion, and dynamic scenario-based training. The findings underscore that maritime helicopter safety requires a paradigm shift—from reactive accident investigation to proactive, systems-based safety design. This approach not only enhances operational reliability but also aligns with modern safety science principles, ensuring mission success without compromising human life.