The value of runway time slots for airlines

In flight scheduling, airlines usually determine optimal timing for their flights to respond to time-dependent demand and the requirement of frequency plans, of available fleets and of aircraft routings. Nevertheless, it is unavoidable that some flights cannot actually operate at their expected time because of the capacity limit of the airport runway. Thus, adjustments have to be made by altering some flights from their optimal times. Scarce runway time slots represent a resource whose value to the airline may be determined from the impact of such re-scheduling on the objective function of the original schedule. In this paper, we first analyze the relationship between rescheduling of flights and airline profit. To assess the impact of flight rescheduling a minimum-cost flow model is constructed. Solving this model gives a new optimal schedule under the condition of rescheduling specific flights at specific time slots. Based on this new optimal schedule the value of specific time slot at specific airport runway is calculated. The method is demonstrated on a sample airline flight network. The model developed can be used for congestion pricing, runway slot auctioning or adjusting airline scheduling programs to accommodate runway capacity constraints.