Simulated Safety Risk of an Uncoordinated Airborne Self Separation Concept of Operation

Abstract

This paper evaluates through Monte Carlo (MC) simulation a model of an airborne self separation concept which has been developed for use under low en route traffic conditions such as encountered over the Mediterranean area. In this self separation concept, each aircraft is equipped with an Airborne Separation Assistance System (ASAS) that proposes uncoordinated changes of its own aircraft path in order to resolve a conflict with the nearest other aircraft. For three encounter scenarios, probabilities for violating minimum separation and for near-mid-air and mid-air events are estimated through rare event MC simulation. The paper presents quantitative risk estimates for several scenarios, and provides an interpretation of these results for the model of the airborne self separation concept considered. This provides novel insight in the efficacy of airborne conflict resolution management, and shows that uncoordinated airborne self separation can be very effective in safely handling low density en route airspace. It also shows that events of multiple conflict clusters may grow in size more rapidly than an uncoordinated airborne self separation may be able to solve. The insight gained shows developers of airborne self separation which issues are key for improvement in order to safely accommodate future high en route traffic densities.