Abstract: The apparatus has an operating structure which is suspendable, by means of cables, from the barycentric hook of a helicopter and is provided with an orientatable arm having a cleaning head rigidly associated therewith. The cleaning head is provided with supports for suspending rotating cleaning brushes actuated by motors. Part of the suspension support is fixed and is constituted by a frame connected to the orientatable arm, and a movable support is supported by the frame so as to be oscillatable and is controlled by motors which allow to move the related brush or brushes from an open approach position to a closed operative position in which the set of brushes of the head embraces the set of insulators.

Abstract: The device is constituted by a structure which is intended to be suspended from a barycentric hook of a helicopter and comprises a first section with at least two facing magazines, each of which is suitable for containing and distributing, in a relationship of mutual juxtaposition, a plurality of half-spheres for the composition and installation of a corresponding plurality of marker balls; and a second section, arranged below the first one, which comprises means for the positioning of the entire structure on the cable of the overhead line and means for installing the facing semi-spheres which comprise fluid-actuated jack elements suitable for mutually compressing and connecting the semi-spheres to thereby form and close the marker balls on the cable.