Batteries have a substantial impact on the weight of electric Unmanned Aerial Vehicles (UAVs). With fuel cells being considered a possible alternative to batteries, the present work aims to design a fixed-wing UAV with vertical take-off and landing capability and a fuel cell-based propulsion system. Building on the tactical requirements of the Portuguese Air Force, this project covers all phases of aerodynamic, structural, and propulsive design, in which Blade Element Theory, Computational Fluid Dynamics, and Finite Element Method analyses were used. The final design resulted in an inverted V-tail, 21.7kg take-off weight UAV capable of three hours of flight time, more than twice the endurance of a battery-propelled version. To further stimulate scientific knowledge sharing, the authors have made all simulations and Computational Aided Designs available to the public via repository.