VTOL aircraft concept, suitable for unmanned applications, with equivalent performance compared to conventional aeroplane

The UAVs business experiences currently a strong growth in particular thanks to the popularisation of its mini class (e.g. DJI Phantom, Parrot Bebop...). Nevertheless, there is still a need for more capable aircraft, mainly in terms of payload and endurance, in both military and civilian markets. This type of aircraft is historically known as the tactical class, which is a compromise between the affordability of the mini class and the capacity of MALE class. It was paradoxically the first class to be developed, long before common drones started to be sold in department stores. Contrary to the mini class drones, which are mostly hand operated, tactical aircraft face the main issue of requiring an airfield for take-off and sometimes for landing, when not using a parachute. Such a problem could be solved by providing the drones with a STOL (Short Take-Off Mass) capacity or even better a VTOL (Vertical Take-Off and Landing Mass) ability. The former is partially proposed by most models present in the market by using most of the time external systems (e.g. Flight deck, catapult, ramp...). However, although there have been several attempts to provide the later, using often a helicopter configuration, resulting aircraft have not achieved the performances of classical aeroplanes. This article introduces a new configuration of VTOL aircraft, particularly well adapted to heavy UAVs. A general sizing is carried out in order to meet typical performances required by the tactical class. Even if only the results of the conceptual design are available for now, the VTOL capacity of the drone seems to be obtained with negligible impacts to its overall performance, which is comparable to fixed-wing drones.