EASA 2018-0292

Requires a one-time detailed visual inspection of the tail rotor slider assembly for corrosion and conditions and, depending on findings, replacement or repetitive inspections. Prompted by a case where a tail rotor slider assembly was found fractured in service during a post-flight inspection. The bushing and the actuator rod included in the tail rotor servo were also found partially damaged. A subsequent investigation revealed that the failure was due to fatigue, initiated from corroded areas localized on the surface of the slider characterized by circumferential refinishing signs. The presence of circumferential finish signs is consistent with sanding operation accomplished on the fractured area of the slider. However, the AW139 maintenance manual does not contain instructions to apply sanding on the slider surface as this operation might remove corrosion protection of the part.