Conceptual and Preliminary Design of a Long Endurance Electric UAV Thesis. Nov 2016 129 pages https://fenix.tecnico.ulisboa.pt/downloadFile/1407770020545502/Luis_Parada_= Thesis.pdf Abstract The present thesis documents the conceptual and preliminary design of a solar long endurance Unmanned Aerial Vehicle (UAV). Having in mind surveillance goals, the mission profile requires an initial climb, at a rate that allows to ascend 1000 m above runway in 10 minutes, followed by cruise with an endurance of 8 hours and a range 200 km during the equinox. In the conceptual stage, several aircraft configurations were evaluated considering the mission requirements. Resorting to the Analytic Hierarchy Process methodology, the rear pusher V-tail airplane concept was chosen through pairwise comparisons between 10 mission criteria (Aerodynamics, Structures an Weight, Solar Panels Integration, Propulsion, Manufacturing and Maintenance, Stability and Control, Payload Volume, Remote-Person View Integration, Take-off and Landing and Portable Capabilities) and 8 prospective candidate configurations. A UAV market investigation provided an initial estimate of the empty weight fraction and airframe dimensions. Through bibliographic research, the communications system was defined beforehand and the propulsion system also received an initial estimate. In the preliminary design phase, the airframe was resized by performing a set of fixed point iterations, whose resulting design point ensured it is physically possible to fulfill flight requirements. Allying multiple aerodynamic analyses, performed on a low Reynolds number computational tool, with the ascertained efficiency of the propulsion system, power consumption at each mission stage was determined under ideal weather conditions. The solar energy received by the photo-voltaic arrays installed was determined in a single location applying a theoretical irradiation model in different seasons of the year. It was verified that in the March equinox endurance reached 7.5 hours, while in September its maximum increased to almost 10 hours. An aircraft CAD assembly was modeled without internal airframe detail. The developed parts include a three-piece 5 meter span wing, a fuselage composed by two connectable pieces, totaling 1.9 meter length, and two individual V-tail halves. On-board propulsion and avionics components were also modeled in a simplified way, as solids of uniform density. A flight stability analysis was performed, resulting in a static margin of 5.6% with null Cm in cruise conditions. Looking at a future detailed design, the cruise flight envelope was created and the wing pressure distribution was obtained --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .