In the United States, the principal reason behind flight delays is the airport capacity. Many major airports suffer from the incapability of satisfying all the demands. In this paper, we investigate the effects of the dynamic distribution of the airport's capacity on the total delay. Despite the relation between departure and arrival capacities, none of the previous works on air traffic flow management has addressed this problem. The proposed model considers departure and arrival capacities as decision variables. It minimizes the total delay and considers various management policies as ground and air holding, rerouting, and flight canceling. Our results revealed that adopting this approach might reduce the operation cost and minimize delays. Moreover, it precisely allocates the optimum needed capacity for the departing and landing flights.