Skyhawk 172/Cutlass 172
Maintenance Airframe; Maintenance Inspection Authority; Maintenance Powerplant
Maintenance Inspector 12; Maintenance Lead Technician 11; Maintenance Technician 34
Distraction; Training / Qualification
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Inflight Shutdown
Human Factors; Aircraft; Procedure
During engine installation; I failed to install cotter pin in throttle control attachment nut and bolt. During flight; vibration loosened the nut and it fell off allowing the bolt to also fall free and resulting in loss of connection of the throttle control at the fuel servo. The engine speed remained at 2100 RPM. The pilot aligned with the runway and used mixture to shut down the engine when reaching the runway was assured. A power off landing was performed and the aircraft was undamaged then towed to the maintenance area where I discovered what had occurred. We are in the process of modifying policies and procedures to prevent recurrences of this incident.
Maintenance Technician failed to install cotter pin on throttle control resulting in engine shutdown in flight.