Impact of optimized trajectories on the air traffic flow management

Abstract

Multi-criteria trajectory optimization is expected to increase aviation safety, efficiency and environmental compatibility, although both the theoretical calculation of optimized trajectories and their implementation into a safe and efficient Air Traffic Flow Management are not to the extent to which they may be applicable right now. The final domain of objective functions, from which the best available values shall be selected, is rarely quantifiable due to the competitive stakeholders. Furthermore, operational uncertainties complicate the definition of an optimized trajectory. These uncertainties may arise from external dynamic influences, Air Traffic flow Management interactions, severe weather conditions or operational changes in the airport management. In this study, the impact of multi-criteria optimized free route trajectories on the Air Traffic flow Management system is analyzed in detail and compared with a validated reference scenario, which consist of real flown trajectories. This kind of methodology requires trajectory optimization and a fast-time simulation tool. Therefore, the TOolchain for Multicriteria Aircraft Trajectory Optimization TOMATO which main task is the multi-criteria optimization of trajectories is compared with the fast time Air Traffic Optimizer AirTOp tool, which was also used for the simulation of the reference scenario and for the assessment of the impact on the Air Traffic Flow Management. Significant differences between the reference scenario and the optimized scenarios can be identified, especially considering the task load due to frequent altitude changes and rescinded constraints given by way points in the reference scenario. The latter and the strong impact of wind direction and wind speed cause interesting differences in the patterns of the lateral trajectories in the air space with significant influence on the air space capacity and controllers task load.