Rotorcraft with at least one main rotor and at least one counter-torque rotor

摘要

The invention is related to a rotorcraft 1 with at least one main rotor 1 a and at least one counter-torque rotor 11a, comprising: at least one duct-type portion 10 provided with a shroud 3 that defines at least one transverse duct 6, said at least one counter-torque rotor 11a comprising a plurality of counter-torque rotor blades 13 and being rotatably arranged within said at least one transverse duct 6, and said shroud 3 being equipped in the region of said at least one transverse duct 6 at least partly with a liner arrangement 3a, said liner arrangement 3a being at least adapted for reducing generation of aerodynamic noise resulting from blade tip clearance vortices occurring during rotation of said at least one counter-torque rotor 11a inside said at least one transverse duct 6 in operation of said rotorcraft 1.