This paper presents a system identification method to derive accurate mathematical models for an unmanned circulation control aerial vehicle (UC2AV) that account for the effects of circulation control (CC) on the vehicle dynamics.The X-plane flight simulator and the CIFER system identification software are utilized to first derive simulation models to verify and validate the proposed system identification methodology.This is followed by flight tests to derive mathematical models and stability derivatives for the aircraft with CC-on and CC-off.Flight tests indicate a nose down pitching moment effect induced by CC,which in t alter the UAV trim values and dynamics.Analysis of the two sets of mathematical models reveal that CC changes the longitudinal trim values and improves the lateral maneuverability of the UAV.Verification experiments indicate an acceptable match between the derived models and UAV dynamics by calculating root mean square (RMS) error values and by quantifying the model predictive ability through calculating the Theil inequality coefficient (TIC).