Research on Collision Risk of Vertical Separation Minima Based on EVENT Model

With the increasing traffic flow,the separation standard is required to be reduced in order to enhance airspace capacity and decrease delays.The reduced separation minima is able to be applied to the air traffic management if it is proved to be safety,so collision risk for different vertical separation is evaluated in order to meet the target level of safety.A vertical collision risk model is established and the calculation methods are deduced.Finally how the vertical separation influence collision risk is addressed and the results show that the collision risk meets the safety requirements if vertical separation minima are reduced to 300 meters,and the collision risk maintains safety level in the next fifteen years with the increasing traffic flow.