Evaluation of separation strategies for unmanned aerial sytems

Abstract

This paper analyzes loss of separation scenarios when an Unmanned Aircraft (UA) enters in conflict with a much faster airplane flying at the same altitude. Separation distances are analyzed in terms of minimum heading changes and reaction times. Results show that maneuvers need to be performed well in advance if the (low-speed) UA is the aircraft that changes its heading. In some cases the time in which the UA and the intruder are in conflict could be too long, and may even involve multiple airliners flying over the same airway. Given that standard separation strategies may have a negative impact on the UA mission, in this paper a set of pre-planned separation maneuvers are proposed. These maneuvers aim to improve the situational awareness of both air traffic controller and UA pilotin- command, but also to disrupt as less as possible the mission performed by the UA and to minimize the uncertainty in the reactions the UA may adopt autonomously if the link with the ground station is lost. Some preliminary real-time simulations are shown, using a UA ground station simulator linked to a air traffic control simulator.