Abstract:On the basis of analyzing historical fault data of aircraft equipment, this paper fully analyzes the main influencing factors of conducting criticality analysis(CA) during the storage and maintenance process of aircraft equipment. Using weighted methods, an evaluation model is established to prioritize the importance of the main functional units of aircraft equipment. Then, combined with Monte Carlo methods, the inertial measurement unit(IMC) was iden-tified as a key functional unit(KFU) through statistical analysis, providing reference opinions for gradually im-plementing aircraft condition maintenance.