In this paper, an augmented optimal LQR control system design procedure has been implemented on the longitudinal flight dynamics of a theoretical UAV, which has been studied in Faculty of Aeronautics and Astronautics of Istanbul Technical University. Throughout the dynamic modeling, open loop dynamics has been investigated and the modes of the longitudinal flight have been inspected. Concerning the open loop time domain responses, an augmented LQR control system design has been applied on the system dynamics. It has been observed that the lightly damped mode could be suppressed in a great manner. In addition, remarkable settling time and actuator signal values has been achieved. Computer simulations show the effectiveness of the proposed approach.