Miniature unmanned aerial vehicle (UAV). Computer artwork of the 'Mirador' UAV. It was designed by the French defence research agency ONERA and the Belgium Royal Military Academy of Brussels. This UAV is a fixed-wing propeller-driven aircraft powered by a fuel cell. It measures 25 centimetres long and can fly for 20 minutes. Miniature UAV aircraft equipped with small cameras and other sensors are being designed for military and civilian surveillance.