Unmanned aerial vehicles (UAVs) powered by electric motors are in an advantageous position because of their properties, such as low noise and thermal footprint, high efficiency, and zero emissions. Lithium-based batteries have restrictive factors for flight duration due to its low energy density, difficult, and expensive charging methods. It is aimed to extend flight duration of a battery powered mini-type UAV with a combined system, which includes a 200 W polymer electrolyte membrane ( PEM) fuel cell, a hydrogen generation system based on in situ hydrolysis of sodium borohydride, a hybrid power management system consisting of fuel cell and battery, and an embedded control system. It is observed that a fuel cell-based energy system is able to extend endurance by twofolds compared with an only battery powered system. This is the first study in the literature that investigates the flight duration of UAVs in battery versus fuel cell according to actual flight data.