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This paper deals with the preliminary design of bionic flapping wing vehicle. The design is driven by its requirement and objective namely the maximum weight should be less than 0.5 kg with 1.5 m wingspan. In the conceptual design, the wing planform, wing structures and system of flapping mechanism will be considered to find the initial configuration and then continued the sizing of the flapping vehicle. The analysis of designed flapping vehicle is increasingly complex due to firstly the generation of time-dependent aerodynamic forces and moments from unsteady flow around the flapping wing, secondly, flexible wing structure which generates higher thrust may cause a structure failure and thirdly, a flapping mechanism system generating differential flapping motion for the vehicle maneuver. The aerodynamic analysis for given flapping motion model is carried out using Computational Fluid Dynamics method based the solution of unsteady Reynold Averaged Navier-Stokes equations and the structure analysis is conducted with the input of aerodynamic loads using Finite Element method to find critical stresses that may cause a structure failure. As a solution of differential flapping two controlled servos are used. The architecture of electrical system is made to analysis of the distribution of data signal and power. The flight maneuver is achieved by changes in flapping frequency and sweeping angle. The selection of system components is performed by considering weight constraint. The flight maneuver is achieved by changes in flapping frequency and sweeping angle. The wing platform has elliptical shape with airfoil maximum camber of 6% chord at a quarter chord. The outer body and wing are made of foam laminated by glass fibre with the foam density of 0.045 g/cm3. The horizontal tail is made of mylar film with density of 1.38 g/cm3 and its area of 168.3 cm2. As simulated results, the amount of total lift is 4.18 Newton generated at 6 Hz flapping frequency.

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HALE UAV needs solar energy to maintain its flight in the day and night. The solar panel located on the upper surface may potentially affect aerodynamic characteristics of the HALE wing. The solar panel generates a heat resulted from solar radiation absorption and surface roughness which becomes parameters to be studied. To identify the phenomena of interaction of flow motion and the heat as well as the roughness, dimensionless numbers such as Reynolds Number (Re), Nusselt Number (Nu), and geometry reference (Ks/C) are used. The simulations for flows at the numbers are conducted using CFD method based on the solution of RANS equations. As a result, the heat transfer gives significant change in flow density near the surface which causes buoyancy effect and the change of flow velocity profile, while the roughness influences the flow characteristics disturbing the flow to become turbulent. They increase aerodynamic drag of 2.6 % and aerodynamic efficiency in the amount of 5%.