EASA AD CF-2020-15
Tail Rotor Drive — Failure of Tail Rotor Drive Shaft Coupling Bolted Connections
Canadian Airworthiness Directive CF-2020-15 addresses the failure risk of tail rotor drive shaft coupling bolted connections on Bell Textron Canada Limited model 206 series helicopters, including 206, 206A, 206B, and 206L variants. The directive mandates replacement of certain MS21042-series nuts with more reliable NAS9926-series nuts or alternate parts to prevent loss of tail rotor drive and potential loss of helicopter control. It also covers specific configurations affected by Supplemental Type Certificates SH2750NM and SH99-202 and provides tailored corrective actions for different helicopter groups.
Airworthiness DirectiveMaintenanceSafety MgmtAir Comm Corporation CAA UK AAN 25273Bell 206Bell 206ABell 206BBell 206L