Flight centric complexity and allocation of flights to controllers

Within the recent Trajectory Based Operations (TBO) framework for air traffic management, this communication addresses the problem of assigning flights to controllers. A new flight centric complexity measure of air traffic is adopted to characterise the traffic complexity of each flight and then to quantify the workload resulting from its supervision by controllers. Within the TBO framework, at the pre-tactical level, an original flight centric optimal assignment problem of flights to controllers is formulated. The solution of this problem determines, on the one hand, the size of the control during a given period of time, which is only a step towards the full sizing of the ATCO workforce for an entire day and, on the other hand, an optimal distribution of the traffic control workload between controllers and the corresponding flights under their supervision. The computational complexity of this combinatorial problem leads to the development of an approximate solution method to deal with it. A heuristic is effectively developed to provide a feasible solution at an acceptable computational cost, allowing the treatment of problems of large dimension. A case study is presented to compare the performance of the solution provided by the heuristic with three practical methods. The proposed heuristic appears to be superior to these methods, and the performances that can be expected from it are: feasibility with respect to capacity constraints, minimisation of interactions between controller teams, and balanced workload distribution. Then, tactical issues are introduced and different schemes, all based directly or indirectly on the introduced flight centric complexity measure, are discussed to face operational disturbances and air traffic conflicts.