Aircraft EWIS safety risk assessment method

The invention discloses an aircraft EWIS safety risk assessment index system construction and assessment model establishment method, and relates to the field of aviation electrical systems and the field of aircraft safety risk assessment. Due to the facts that many factors need to be considered in aircraft EWIS safety risk assessment and influence degrees of different levels of factors are different, influence factors causing EWIS failure are divided into three first-level indexes, 13 second-level indexes and 38 third-level indexes according to cable parameters, surrounding environment factors and installation and protection modes, and an EWIS safety risk assessment index system is constructed. Taking an open circuit failure and a short circuit failure of the EWIS as examples, respectively calculating the weight of each level of evaluation index based on TFNAHP and TFNDEMATEL, dividing risk levels by a cloud model, calculating the cloud model digital characteristics of each level of evaluation index, and comb