Bonanza 36
Maintenance Airframe; Maintenance Inspection Authority; Maintenance Powerplant
Training / Qualification; Communication Breakdown; Situational Awareness
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Aircraft Aircraft Damaged; General Maintenance Action
Incorrect / Not Installed / Unavailable Part; Procedure; Human Factors
Customer requested five out of six cylinders be replaced during Annual Inspection. During correspondence with Supplier of the cylinders; our Parts Manager was misinformed as to the Part Number (P/N) Cylinder Kit required. The Installer (Mechanic) failed to check the Applicability List (A/P) and I failed to catch the error subsequently during the inspection. I then returned the aircraft to service following an Annual Inspection (A/I) June 2012. Considering the wrong parts were installed in the engine; the engine was not in an Airworthy condition. The aircraft was flown for approximately 100 hours and one year. Oil analysis discovered high aluminum content and a third party [Repair] facility found piston skirt wear and further discovered the incorrect part had been installed. I was contacted by the aircraft Owner June 2013 and have since been assisting with the repair of the engine. Summary errors: Part's Department didn't confirm; Installer didn't confirm and the Inspector didn't catch the error. In the future; the Parts Department will verify by application the part numbers to be ordered. The installer and other staff will be retrained to check applicability listing and the Inspector will increase his awareness of inspection of Critical Components.  The correspondence with the Manufacturer should have been verified with other documentation for the make and model of engine.  Also a factor was even though the Supplier identifies the applicable engine on the piston; the piston comes preinstalled and 'if the cylinders are installed and operated in a timely manner; there should be no need to completely remove the piston from the cylinder bore at assembly.'
A Repair Station Aircraft/Engine Inspector (IA) reports about a summary of errors that contributed to five out of six incorrect cylinders being installed on a Continental IO-550B Engine. The Beech A36 Bonanza had flown approximately 100 hours and one year when an Oil Analysis discovered high aluminum content in the oil.