A novel slot optimization model for congested airports integrating IATA priority and operational priority

The Worldwide Slot Guidelines (WSG) are currently widely adopted for airport slot demand management. In some busy airports, coordinators are responsible for allocating slots according to the priority order outlined by the WSG. Particularly, historical slots with the highest priority should be directly allocated to the airline carrier holding that slot in the following same season. However, when airport capacity decreases, there may be situations where historical priority slots cannot be met, rendering the existing allocation guidelines ineffective. Currently, no research considers this situation. To complement the existing coordination priority, this paper first defines a new priority category from an operational perspective, referred to as operational priority. Furthermore, a weighted dual-objective slot optimization model is constructed, integrating both coordination priority and operational priority within the same optimization model framework. A constraint-based hierarchical search strategy is adopted to find the optimal results for different priority slots. Applying the model to Shanghai Pudong International Airport (ZSPD) in China, experimental results show that the proposed model can effectively meet the requests of airlines, with a slot adjustment amount of only 3.15% and a maximum displacement of fewer than 40Â min. Since the proposed model considers operational priority, the optimized results regarding temporal and spatial distribution are more reasonable, effectively reducing flight delays and improving operational efficiency.