PRELIMINARY DESIGN OF AN INOFFENSIVE FIXED-WING UNMANNED AERIAL SYSTEM

Aim of this paper is the preliminary design of an harmless fixed-wing unmanned Aerial System. To improve application fields, endurance has been selected as fundamental performance and the blended wing configuration has been chosen. So the fuselage has the same airfoil of the wing and contains all the payload. In this way the drag has been reduced. Because of the blended wing arrangement, to control pitch and roll elevons have been introduced. To guarantee the directional stability, winglets have been used; besides winglets increase the equivalent aspect ratio and consequently reduce the drag and improve the endurance. The selected propulsion system has been based on an electrical brushless engine with a LiPo battery and a pusher propeller. According to ENAC 2016/003-NAV guidelines, propeller is made of flexible materials. The selected engine needs of limited electrical power. The propulsion system and the power distribution unit have been chosen optimizing both performance and safety. According to EANC guidelines, the electrical system has been provided with a fire protective case, in this way risks for people or infrastructures in the remote case of a crash have been reduced. A prototype has been realized with medium density EPS, according to ENAC guidelines.