Shape , dimension , moving direction , rotating direction and light radiation intensity are important dynamic characteristics of the object in space telemetry and telecontrol video auto-tracking system. In the paper two directions coefficient of the object in video auto-tracking system’s converter plane coordinate were defined :the object moving direction coefficient and the lineal direction coefficient ,it combines the object projection with the object moving trail ;and a converter plane coordinate formed by the orthogonal A and E was defined ;it combines the moving direction in which the object moves on the video auto-tracking system’s converter plane. An analytic algorithm is presented in the paper , and based on which flying trail data is simulated and analyzed primarily.