Investigation of aerodynamics and longitudinal stability of unmanned aerial vehicle with elevator deflection

Abstract

The elevators are usually hinged to the horizontal tail, which acts as a balance and controls the altitude, establishes a steady motion for the aircraft at all lift coefficients. During elevator rotating, the aircraft needs to be stable to establish a new altitude. Longitudinal flying qualities depend on the aerodynamic force of components (wing, tail, fuselage) and configuration of the aircraft. The horizontal tail has a major role in the value of the airplane's pitching moment (due to the long arm from the aerodynamic center of the tail to the center of gravity) for equilibrium and stability of the aircraft. The horizontal tail should be considered an aerodynamic component behind the main wing, influenced by the wing downwash wing rather than just a minor wing. Therefore, method of solving the differential equations for viscous flows through unmanned aerial vehicles (UAV) was used. Small disturbance theory was used to calculate the longitudinal stability of the UAV when controlling the elevator. Flying qualities were assessed so that changes in the aerodynamic characteristics of the wing, tail, fuselage and configuration of the aircraft may be required.