Aircraft maintenance affects to keep safety, comfort, and on time operation of airplane, however, it is not easy to figure out the optimum number of maintenance workers. The air companies never easy to find the optimum number of maintenance workers since they are needed to be paid high salary as well as high level of technology. A simulation model to calculate the optimum number of maintenance for components is developed to avoid using the simple formula generally using in practice. The model is designed to use only with minimum using available data in field since not the data necessary for simulation models are ready to collect. The waiting time and required number of maintenance are analyzed along with common usage of expensive facility and number of maintenance workers. The economic number of maintenance workers as well as extra number of components are figured out based on the analysis.