The major mission object of a launch vehicle is to settle precisely a payload on the designed orbit. For the design process of most launch vehicles, the multi staged rocket system using the propulsion system such as the solid rocket motor or the liquid engine is selected to complete the mission. For the usual launch vehicle, the separation of the lower stage and the payload fairing which is the structure to protect the payload happens firstly before the separation of the payload. The structure after the separation of the lower stage and the payload fairing is called an orbital block consisting of the payload, the propulsion system, the electric bay, etc. The flight conditions of an orbital block such as the velocity, the altitude and the attitude angle are determined according to the mission trajectory. Orbital blocks usually fly at the high altitude belonging to the rarefied flow regime.