It is necessary to carry out the static force measurement wind tunnel experiments during the development of large civil aircraft in order to obtain the aerodynamic characteristics at low angle of attack condition. However, for aircraft stall/departure/spin research, static force measurement experiments are not enoughthe dynamic characteristics of aircraft stall is not obtained. Subscale model free-flight is a kind of dynamic experiment with aircraft subscale model to investigate aircraft stall/departure/spin problem, which includes wind tunnel free-flight test and atmosphere free-flight test.