Research on Collision Risk Model in Free Flight Based on Position Error

Abstract

The problem of collision risk in free flight with a certain safe distance is studied. In free flight, the collision risk is closely related to the aircraft position error. With the stochastic characteristics, we set the position error to satisfy a three-dimensional Gaussian distribution, and established the position error model of the aircraft in the horizontal and the vertical direction. Determine the location and the time when the two aircrafts are closest by the nominal route, and calculate the probability that the aircraft appears at any point near the theoretical position by the position error model. Because every collision occurs after conflict, we calculated the conflict probability first, and then modeled the collision risk given safe distance in free flight. Moreover, the algorithm is presented to use this collision risk model to obtain the minimum safe distance with a safety target level. The results of case study show the feasibility of this model.