This paper presents a conceptual design project developed at the Warsaw University of Technology and focused on an unmanned aerial vehicle being able to fly at low and medium altitude, with a special emphasis put on selecting the platform best suited for the planned mission. Design and research activity necessary to complete the project successfully is based on the international experience gained by the university team within a number of the past very successful projects, mainly projects supported by European Union within the V and VI scientific frameworks. The project deals with a highly maneuverable unmanned aerial vehicle of low gust sensitivity and reduced radar, infrared, and acoustic signature. Aircraft mission, power unit, aerodynamics and many design details are shown and discussed.