An unmanned aircraft includes three parallel beams extending in at least one longitudinal direction X from a rear side to a front side of the aircraft, the central beam forming a main fuselage containing a powertrain, with a propeller of diameter D configured to be driven by the powertrain being attached to a front end of the central beam, each side beam being at a distance L/2 from the central beam and each side beam supporting a radar at a front end of the beam.