Two Numerical Studies for Longitudinal Movement of a Canard UAV with Vectored Thrust

Abstract

This work presents a study concerning the possibilities to improve the longitudinal dynamic of a canard UAV using vectored thrust. It is followed to harness the advantages of canard configuration of UAV and to obtain further a better longitudinal dynamic, able to fulfil more complex missions than canard UAV without vectored thrust. There are tested two methods. The first uses the UAV polars obtained in XFLR 5 and extended, using literature experience, a little bit over the stall angle. By this method is determined the necessary gain between the elevator steering angle and thrust deflection angle in order to maintain the UAV in landing configuration (flaps down) to the optimum angle of attack for landing. Using this method is studied also the effect of vectored thrust in maneuver, in cruise configuration. Step signal on the elevator, thrust and both commands simultaneously are applied on the UAV without and with vectored thrust and are identified the advantages of vectored thrust in this situation. The second method uses the polars of the UAV components obtained in XFLR5, extended independently up to a little bit above each stall angle. By this way is studied the effect of the vectored thrust on the atack angle in horizontal flight for the UAV in cruise configuration. There are obtained horizontal flight parameters (speed, elevator steering, angle of attack and thrust), when vectored thrust is used. It is followed to obtain results for attack angle as high as possible. Both methods are limited by the results obtained in XFLR 5, that can’t determine polars at atttack angles near stall, and for the second method, by the aerodynamic interferences between UAV components.