Global time-based conflict solution: Towards the overall optimum

The goal of future Air Traffic Management (ATM) is simple: every airborne vehicle shall fly as efficient as possible while keeping safety and other key performance areas high. 4D-Trajectory-Based Operations (TBO) promise improved efficiency, safety benefits, and high predictability in advance. Highly accurate 4D-trajectories allow early conflict detection and efficient conflict resolution. Independently predicted 4D-trajectories ensuring highest efficiency for everyone create conflicts already with low traffic densities. These conflicts are usually solved by lateral, vertical, or time-based avoidance. This paper is about time-based conflict avoidance in its most efficient way. Flight duration is kept constant allowing the aircraft to fly its preferred optimum profile. Adjustments are done on whole flights by shifting them by some minutes in time. The paper presents results from conflict resolution on an ECAC wide traffic scenario holding 33k aircraft with 29k initial conflicts. The idea is to de-conflict the busiest day above Europe 2011 in its most efficient way.