Joint fleet scheduling and cargo flow allocation for air cargo services

We propose an integrated optimization model designed for the air cargo service network scheduling problem, focusing on next-day delivery. Our model effectively combines dedicated cargo aircraft with belly capacity from passenger airlines to jointly determine optimal cargo flight schedules, cargo fleet routes, and cargo routes. To enhance the efficiency of the air cargo service network, we incorporate through cargo connections into the cargo routing problem. These connections occur when the same aircraft operates consecutive flights within a cargo route. A tailored column-generation-based heuristic is developed to solve the problem. We conduct an extensive set of experiments to validate the performance of our proposed model and algorithm based on the data from our industry partner company. The computational results demonstrate that for small-scale instances, our algorithm rapidly identifies near-optimal solutions. Meanwhile, for medium- and large-scale instances, it consistently delivers superior solution quality compared to the commercial solver. Ultimately, our study highlights that the inclusion of through cargo connections not only enhances the overall service level of the network but also leads to increases in flight load factors and reductions in operational costs.