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In this paper an attempt is made to develop a model to increase profit-making in air transportation system taking into consideration of the most important problems encountering the system. Utilizing the outcomes of this model, general policies for investing capital to carne out profit-making projects can be recognized.In the presented model the least squares and non-linear optimization methods have been utilized to recognize unknown quantities. In addition, to simplify the developed model and obtain numerical results, the available potential for increasing profit-making in the system has fallen into three major categories. Moreover, profit-making sources have been classified in five distinguished sections.Since recognizing the utilized coefficients in the model claims extensive studies, in most of the cases, the air transport experts and authorities comments have been taken into consideration and an attempt has been made to adapt these coefficients to real values.