From free-route air traffic to an adapted dynamic main-flow system

Abstract

Actually, en-route flight traffic is carried out on a system of predefined routes with a low number of intersections between aircraft trajectories to enable the air traffic controllers to control and supervise the traffic especially around these intersections. Consequently, a route system always leads to a low ratio of used to unused airspace. To improve this, the idea of free routing has been developed, where every aircraft uses the direct connection between origin and destination airport generating a traffic distribution which uses nearly every part of the available airspace. As consequence many intersections between flight trajectories arise which is more difficulty to handle for controllers. Our approach presents a compromise between the flexibility of free routing and the easier surveillance for controllers in case of a predefined route-network. For all free routing trajectories the intersections between them are clustered and used as intersection points in a so-called main flow system. With additional processing a system of main-flows is identified and the number of intersections is reduced to an acceptable amount. Tests with two different free routing scenarios delivered promising results. In this paper, the theoretical background and the results are presented. Furthermore, we see our research as an important contribution to the development of future airspaces in the highly dynamic urban environment.