Flight Routing and Scheduling with Departure Uncertainties in Air Traffic Flow Management

Uncertainty takes different forms in air transportation systems. One form is demand uncertainty which is mainly due to the root cause of aircraft departing in deviated time slots. This can lead to severe consequences, including capacity violation in air routes. The current Air Traffic Flow Management (ATFM) literature does not consider demand uncertainty in flight scheduling. However, in reality, most of the flights do not take off at the designated time slots, thus can lead to an unexpected number of aircraft to appear in some links. This creates several difficulties in air transportation systems, including higher workloads for air traffic controllers and higher delays and travel costs. In this study, we propose a novel flight routing and scheduling scheme while considering the demand uncertainty present in the system. Our objective is to route and schedule flights to minimize the overall network delay while satisfying all link capacity constraints even under demand uncertainty. To this end, when estimating the flight parameters such as location and time, we consider a range of values that the flight can take due to its departure uncertainty rather than a discrete single value. The problem is formulated as a Mixed Integer Quadratic Programming (MIQP) problem. With the help of simulation, we show that the proposed approach helps to eliminate the capacity violation completely from the system while ensuring a low amount of overall flight delay.