Abstract: The common cause failure events usually happen in the weapon and equipment for implementing the combat mission. The analysis of common cause failure events is of practical significance to the precise equipment support. A kind of random common cause failure has not been considered in the optimization model of carrying spare parts allocation for the combined arms unit implementing the task. An optimization method for spare parts allocation under random common cause failure is proposed. A spare parts demand model with the condition of equipment fault correlation is established, and an optimal model for carrying spare parts allocation under multiple constraints is developed. The Lagrange multiplier is introduced, and the optimal allocation scheme is obtained using the marginal effect method. A real example is used to verify the validity of the proposed model. The results show that the proposed model can be used to obtain the optimal allocation of multi-constraint spare parts under the condition of the random common cause failure. Key

Key words: carryingsparepart, randomcommoncausefailure, wartime, allocationoptimization, Lagrangemultipliermethod