Jet/Long Ranger/206
Maintenance Airframe; Maintenance Powerplant
Maintenance Lead Technician 3; Maintenance Technician 6
Training / Qualification
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Human Factors; Manuals; Procedure
While performing a transmission and mast replacement on aircraft; the maintenance technicians were installing the drive link collar set onto the splines of the main rotor mast. Following procedures in the Bell Maintenance Manual 206L4 Chapter 6; paragraphs 1-7 we found that the collar was not positioned correctly. The technicians then read the instructions again and realigned the collar set so that it was correctly installed. It was inspected and the splines were engaged per the manuals instructions. From that point maintenance resumed without error and the safety and security checks were performed.
Lead Maintenance Technician reported that a main rotor mast and transmission were improperly indexed during installation and required corrective maintenance action.