The major issue in aircraft industry is aviation safety management because of demand improvement and advancement of the aircraft. This study is to assess the risks for aviation safety management using IRPN( importance-risk priority number) which is added to importance coefficient from RPN(risk priority number). In FMEA, RPN requires the factors like the occurrence (O), Severity (S), and Detection (D) of each failure mode to be precisely evaluated. Therefore, the severity and detection is derived by the value from FMEA of expert group based on the Fuzzy theory. The occurrence is calculated from the accident statistics of IATA(international air transport association) database. Particularly, this study introduces importance coefficient to prevent from RPN distortions. It is also derived from FMEA based on the Fuzzy theory. Finally, the critical ranking of risk factors according to I-RPN is compared with the existing research.