Modeling of collision risk on parallel routes based on spherical protected area

This paper presents an analysis of collision risk on parallel routes, which computes the collision risk through establishing a model under the condition of a given target level of safety. Firstly, the three-dimensional coordination system of the aircraft is converted to two-dimensional coordination system, and then the collision risk assessment model is established by using multi-dimensional random variable covariance matrix on the basis of spherical protected area instead of cuboid protected area in the Reich model. Secondly, arithmetic of separation assessment is established to compute the collision risk under different flight separation. Finally, an example is analyzed, compared the results 1.026 ×10^-12, 3.242×10^-16 and 6.473×10^-25 with the target level of safety 1.5×10^-8 to indicate that the separation of the route is feasible.