Maintenance Airframe; Maintenance Powerplant
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance
General Maintenance Action
Aircraft
Elevator trim actuator removed per Work Order written up by pilots as binding. It was found to have internal damage to one externally threaded screw (lollypop) when torn down. The actuator was observed prior to tear down to have a very narrow band of free movement in both directions then would lock up being impossible to turn by hand. The actuator was damaged internally in a way impossible during service. Proper testing procedures per the CMM (Component Maintenance Manual) 27-10-01 would have rejected the actuator had they been performed after assembly; also post installation checks per the AMM (Aircraft Maintenance Manual) would have found this discrepancy had they been followed. I see no way the externally threaded screw (lollypop) could be damaged after assembly or installation.Where did this actuator come from? Who built it? Who installed it? Are they aware manuals are provided for safe servicing and installation of trim tab actuators?
A Mechanic reported that a Cessna 560XL elevator trim actuator was binding and found to have internal damage.