A synchronized method for airport operation management: gate reassignment and taxi routing

Purpose: With the continuous growth in air traffic demand, airports face significant bottlenecks. A well-planned taxi operation can reduce fuel consumption by avoiding excess waiting and moving with engines on. On the other hand, the gate assignment plan may be disrupted due to disturbances in the flight schedule, which need to be recovered via cost-effective solutions. The paper aims to synchronize two airport operations, namely gate reassignment and taxiway routing, and proposes efficient methods to address this issue. Design/methodology/approach: This paper proposes a time-space network flow model to deal with the synchronized gate reassignment and taxiway routing problem. A free-path setting is adopted where the aircraft can potentially choose any path. Taxiway conflicts, which are the main factors that result in the intractable situation of traditional MIP models, are resolved by a side constraint in the time-space model. Findings: Preliminary experiments show that the linear gap of this time-space model is small, which inspires us to design a diving heuristic to accelerate the computational speed. Extensive experiments are conducted on the Hong Kong International Airport case. The results show that the integrated method outperforms the sequential approaches and the connection-based network flow models. Originality/value: This paper formally defines the problem of synchronized gate reassignment and the taxiway routing problem under the free-path setting. It proposes two models: a connection-based network flow model and a time-space network flow model, as well as an efficient heuristic to solve this problem.