Abstract: The invention relates to a thermoplastic molded part able to constitute a duct of an aerial vehicle or space vehicle, to a method of manufacturing same, and to this duct which comprises said part. For example, provided is a part according to the invention, which has an external surface (2) with symmetry of revolution at least in part, is such that the external surface comprises a multitude of integrally molded depressions (6) which are connected to one another in pairs by crests (7), and that: each of the depressions has a largest transverse dimension D between the adjacently paired crests of between 3 mm and 10 mm, measured in a direction d perpendicular to the crests delimiting each depression, and each of the crests has an apex of transverse width L measured in said direction d, where L<D.