Simulated Annealing for Strategic Traffic Deconfliction by Subliminal Speed Control under Wind Uncertainties

Abstract : This paper introduces an algorithm that minimises conflicts between aircraft at the strategic level taking into account uncertainties on aircraft position due to errors into wind forecast. The strategy relies on subliminal speed control. Owing to the complexity of this kind of optimisation problem, a simulated annealing metaheuristic approach is employed. A scenario with four hours of traffic overflying the Spanish (structured, continental) airspace has been selected. Traffic has been retrieved from NEST Eurocontrol database with the corresponding wind ensemble probabilistic forecasts from the European Centre for Medium-Range Weather Forecasts. Due to uncertainties and to the little range of speed changing allowed by a subliminal control, it becomes not possible to resolve all conflicts. However, their number can be significantly reduced by slightly modifying flight plan speeds while not touching the selected route by the airspace user.