SF 340A
Maintenance Airframe; Maintenance Powerplant
Communication Breakdown; Confusion; Time Pressure; Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Aircraft; Procedure; Human Factors
I was the lead mechanic for a propeller build-up during which #2 and #4 blades were swapped. When the prop was finally put on a plane a month later; the airplane experienced excessive vibration. This is when the prop was inspected and found that blades were installed in the wrong locations. I think the blades were installed improperly because too many people were involved in the build-up. Blades #1 and #3 were installed first so I think we just got confused as to which side #2 went on. Inevitably after installing #2 incorrectly; then #4 would also be incorrect. I think we also failed to double-check our work like we did when installing #1 blade.
A lead Maintenance Technician reported a process failure where propeller blades were installed in the incorrect position during build-up; resulting in vibration when the assembly was installed on an aircraft.