# Impacts of Flight Operations on the Risk of Runway Excursions
## 1 Introduction  
Ensuring safety during the landing phase has always been a top priority for the civil aviation industry. The International Air Transport Association (IATA) Safety Report for 2021 reveals that nearly 80% of all aviation accidents occur during the landing phase. Among the latent conditions that contribute to runway excursions, flight operations account for 28% of the impact, while the influence of the flight operations training system is estimated at 16%. These findings highlight the critical nature of the landing phase in ensuring aviation safety, with operational procedures and training programs playing crucial roles in safeguarding against accidents. Runway excursions have received significant attention in the civil aviation industry. The IATA's 2021 Safety Report [1] identified runway excursions as a high-risk category, constituting 24% of all accidents prior to the COVID-19 pandemic. Over the past decade (2012-2021), runway excursions have been the most common accident category, with 138 occurrences. This category ranks as the third leading cause of fatal accidents, resulting in 93 fatalities across nine accidents. These accidents occurred during aircraft takeoff or landing and were influenced by factors such as unstable approaches, high landing speeds, and slippery runways. According to the IATA Annual Safety Report--2022, there was one fatality attributed to runway excursions last year, with six occurrences of non-fatal incidents involving runway excursions [2]. According to A Statistical Analysis ofCommercial Aviation Accidents by Airbus, the analysis of data from 2002 to 2022 highlights that runway excursions rank as the third leading cause of fatal accidents and represent the primary factor in aircraft structural damage. Runway excursions account for 17% of fatal accidents within various accident categories. Furthermore, within the distribution of accidents based on aircraft damage, runway excursions constitute 36% of cases [3]. Research on runway excursions can generally be categorized into two main types: accident report analysis and exploration of causal and influencing factors. Studies that focus on identifying causes and analyzing factors typically rely on accident investigation reports to determine the contributing factors and propose corresponding improvement measures. Another approach involves analyzing past accidents using accident analysis models to classify and analyze the risks associated with runway excursions, thus providing risk management strategies. Alternatively, researchers may establish indicator systems and weights based on event analysis and expert opinions to conduct risk analysis and prediction for runway excursions [4; 5; 6]. Another category of research focuses on the analysis of exceedance events and the study of distances and landing trajectories in runway excursions based on Quick Access Recorder (QAR) data [7; 8; 9]. In the context of runway excursion research, there has been limited utilization of QAR data for operational risk analysis. Current studies based on QAR data predominantly concentrate on the characteristics and operational risks of operations, but these studies are currently less focused on specific operational nodes. Research on operational characteristics emphasizes feature identification with limited exploration of accident risks. Studies on operational risks mostly focus on analyzing the entire flight process or specific parameters, with limited research combining and analyzing flight parameters. The paper focuses on the risk of runway excursions during the landing phase, categorizing flight operations into styles and analyzing the risk of runway excursions from the runway threshold to the end of the rollout phase. Emphasizing the runway threshold, flare, deployment of speed brakes, touchdown, and reverse thrust activation, the study conducts a detailed analysis of the operational characteristics and associated risks for each style.