Abstract: The invention relates to a convertible aircraft comprising a fuselage (F), a pair of wings (A1, A2) arranged one on each side of the fuselage (F), at least one ducted rotor (1) installed in a horizontal position at one of the ends of the fuselage (F) and a first and a second nacelle (N1, N2) arranged respectively at the tip of each wing (A1, A2) and each comprising a ducted rotor (R1, R2) and being pivotably mounted relative to the fuselage (F). The nacelles comprise at least a first and a second movable flap (V1, V2), which flaps are arranged respectively at the outlet of the ducted rotor (R1) of the first nacelle (N1) and at the outlet of the ducted rotor (R2) of the second nacelle (N2). The aircraft according to the invention thus represents an advantageous solution to any applications involving helicopters and airplanes, particularly emergency preparedness missions, rescue missions, and public or private transport.