Robust Aircraft Trajectory Optimization and its Integration into Arrival Air Traffic Control under Weather Forecast Uncertainty

Uncertainty in weather forecasts increases the complexity of aircraft trajectory optimization and makes trajectory prediction uncertain as well. The resulting 4D-trajectory uncertainty subsequently leads to congestion and capacity reduction of airspace and causes delays. Moreover, it also complicates Air Traffic Control’s (ATC’s) inter-aircraft separation management in an arrival sequence. As weather forecast uncertainty affects both individual trajectories and the associated arrival sequence, both aspects should be considered simultaneously in optimization. However, stochastic aircraft trajectory optimization has never been tackled with multiple aircraft, while stochastic arrival sequence optimization has never considered the trajectories of the sequenced aircraft. Furthermore, research works that integrated trajectories and the arrival sequence in optimization have only been carried out in a deterministic framework. To address these research gaps, this doctoral research develops a stochastic optimization method to simultaneously optimize descent/approach trajectories and the associated arrival sequence, while ensuring inter-aircraft separations under uncertain weather forecasts. We formulate a multi-phase Optimal Control (OC)-based robust trajectory optimization problem for descending/approaching aircraft. The ensemble approach is employed to model the effect of weather forecast uncertainty on a trajectory. We also introduce the ensemble approach into sequence optimization to bring robustness to arrival sequencing. The trajectory and arrival sequence optimizations are integrated into a single robust optimization framework called the integrated robust Trajectory & Sequence (T&S) optimization. This novel optimization method enables simultaneous optimization of trajectories and the arrival sequence in terms of statistical performances of fuel burn, fight time, and airspace throughput. It also allows for limiting the 4D-trajectory uncertainty of each aircraft to below a desired level. The developed ...