M-20 Series Undifferentiated or Other Model
Maintenance Inspection Authority
Maintenance Inspector 25; Maintenance Lead Technician 25
Communication Breakdown; Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural FAR
General Maintenance Action
Procedure; Human Factors
Service was rendered to a Mooney aircraft which led to an annual inspection. This aircraft had been sitting for several years following rumored issues. This work was completed in [the previous year]. The Fuselage was inspected according to Mooney's recommended inspection list. AD's provided by self and the owner were reviewed; verified and/or completed in accordance with service and maintenance guidelines. The aircraft was determined to have had a running engine prop strike and a new two blade prop replaced the previous 3 blade. It was determined according to Lycoming to remove the engine for a tear down and inspection. The owner located a used engine that had been sitting for multiple and unknown years. He took the engine to [an A&P]; for inspection. Parts were disassembled and reassembled and it was test ran for 45 minutes. A log book entry was made by him. Here is a miscommunication issue. It was assumed that [the A&P] was an IA; and that his log book endorsement constituted a completed inspection for return to service. The inspection sign off alluded to that endorsement. It has come to my attention that his credentials only have him as an A&P. This was an error as I signed off the aircraft for an annual inspection. This information was not known at that or any issues. This report is made at the earliest possible time of the knowledge of events as I learned them and became aware of the issues and being presented as timely as possible. Obviously in the future more careful reading and verifying past work by others will be implemented in my aircraft history research for annual inspections paying closer attention to details that may have been overlooked for this event.
A Maintenance Technician with Inspection Authority reported releasing an aircraft for service that had not received a full annual inspection.