A novel probabilistic risk analysis approach for engine bird strike issue applied on the airworthiness regulations

Bird strikes on aero-engines are a significant factor contributing to aircraft accidents. Airworthiness regulations in various countries impose specific requirements on engine resistance to bird strikes. Currently, the International Civil Aviation Organization (ICAO), the Federal Aviation Administration (FAA) of the United States, and the Civil Aviation Administration of China (CAAC) categorize the severity levels of bird species that pose threats to flight safety based on their weight within the relevant regions. Consequently, this thesis introduces a probabilistic risk assessment method based on bird strike severity levels. Utilizing bird strike data from U.S. civil aviation engines as an example, this study assesses the risk posed by birds of different severity levels in U.S. civil aviation. Through this method, the bird strike risk associated with each weight range specified in FAR 33.76 was quantitatively evaluated. This evaluation confirmed that the risk predictions for large birds in current airworthiness regulations align with the intended safety objectives.