Lateral collision risk analysis in air traffic

In order to evaluate the safety of lateral separation minima, the EVENT model is used to build the lateral separation minima meet the target level of safety, and the event trees are used to analyze avoiding systems how to effect the collision risk. Consequently, this paper studies not the safety in separation provision, but the safety of overall ATM system. The results show that the lateral separation minima is related with the area navigation precision, and the lateral separation minima is reduced with the increasing of the navigation precision; the lateral separation minima is reduced through adding the collision avoidance, which improve the airspace capacity and airspace utilization.