Rotary-wing aircraft

A rotary-wing aircraft comprising:

• a fuselage provided with a rotary wing;
• and
• an external device mounted on an outside of the fuselage, wherein:
• the external device comprises:
• a mounting device fixed to the fuselage and disposed so as to project in a lateral direction of the fuselage,
• a mass variation device mounted on the mounting device, the mass variation device having mass that varies as the mass variation device is used during flight of the rotary-wing aircraft, and
• a damper coupling the fuselage to the mounting device,
• the damper supports the mounting device during the flight, and
• the damper comprises a stiffness variable mechanism configured to change stiffness of the damper in response to variation in the mass of the mass variation device during the flight,
• a first end of the damper is fixed to the fuselage at a position higher than the mounting device and a second end of the damper is fixed to an upper side of the mounting device,
• the mass variation device is mounted on a lower side of the mounting device, and
• the damper is configured to suspend the mounting device on which the mass variation device is mounted.