Quantitative forecast model of support equipment based on support activity flow

In order to resolve the problems encountered in the process of forecasting the number of equipment demanded by support system during the design and development phase, including the difficulty to collect the input data of the previous forecast models and their imprecise and unauthentic output results, a quantitative forecast model of support equipment is established based on support activity flow described by functional flow diagrams, which uses the data of support system modeling and the results of supportability analysis as input. First, the average and maximum number of support equipment demanded by the support activities in the bottom of the functional flow diagram is calculated and analyzed; then an approach to sum the average and maximum quantity of support equipment demanded by the support activities with logic relations in the same level of the functional flow diagram is presented, and the average and maximum number of support equipment demanded by the top-level support activity is achieved; thereafter, the quantity of support equipment allocated in the support sites is calculated. Finally, the proposed model is demonstrated via a practical case of an aircraft, which proves that the model is correct and effective.