EASA AD CF-2021-42
Engine Controls — Binding of Fuel Control Unit Push Rod End Bearings
Canadian Airworthiness Directive CF-2021-42 addresses the issue of binding in the fuel control unit (FCU) push rod end bearings on Viking Air Ltd. DHC-6 series 1 through series 400 aircraft, specifically those with lower FCU push rod assemblies part numbers C6CE1398-7, C6CE1398-3 with P/N VSC30-3A rod end bearings, or FAA PMA equivalents. The directive mandates inspections, functional checks, lubrication, and replacement with redesigned parts to prevent engine power control issues. This AD aims to ensure continued safe operation of affected aircraft by mitigating the risk of engine power reduction failure.