Collision risk estimation in terminal area airspace

In order to estimate the collision risk in the process of airspace planning, a collision risk model based on distribution of initial time interval is proposed. In the collision risk model given some airspace planning parameters comprised of separation minimums, flight segment length, speeds of aircraft, the proportion of the aircraft type, flow rate, required navigation performance value, climb gradient or descend gradient are included. The influences of airspace planning parameters on collision risk can be characterized. The results show that vertical separation minimum have greater influences on the collision risk. A method to calculate the collision risk between intersecting flight tracks with planning parameters is developed. These would provide the method and theory to research the collision risk in the field of terminal airspace planning.