Directional drill

A directional drill (10) for directional drilling of arced holes having a predetermined coursein jointed and fractured rock formations, comprising a drill string (11) with a foremost diamond full-face drill bit (20) with a reamer (30) and drive shaft connection assembly(40), wherein the directional drill (10) is provided with a underiying of the drill bit (20) arranged notation preventing assembly (100) including at least one pressure pad or packer element (102) for engagement with a borehole wall by activation by pressure from supply of drilling fluid and displaceable axially along the borehole wall during drilling for fixed orientation of the directional drill (10). Drilling tool with downhole electric power generator assembly (500), wherein the drilling tool comprising a bottom hole assembly (11) with a foremost full-face drill bit (20) driven by an internal drive shaft (150) transferring feed and rotation forces from a drill string of a drill rig onto the full-face drill bit (20), and further comprising a rotation preventing assembly (100) including at least one pressure pad or packer element (102) for engagement with a borehole wall by activation by pressure from supply of drilling fluid, and a downhole power generator assembly (510), wherein the downhole electric power generator assembly (510) is formed by an outer tube (511) housing at least one stator generator segment (512) and at least one rotor generator segment (513), wherein the at least one stator generator segment (512) is arranged to the outer tube (511) and wherein a part or segment of the inner drive shaft (150) is arranged for accommodating the at least one rotor generator segment (513), wherein the stator generator segment (512) is arranged for accommodating the inner drive shaft (150) with the at least one accommodated rotor generator segment (513).