posted on March 12, 2013 15:30
The FAA proposes to supersede an existing airworthiness directive (AD) for Agusta S.p.A. (Agusta) Model A109E helicopters that requires reducing the tail rotor (T/R) blade life limit, modifying a T/R hub and grip assembly, re-identifying two T/R assemblies, clarifying the never-exceed speed (Vne) limitation and reducing the inspection interval.
Since the FAA issued that AD, the manufacturer has redesigned a T/R grip bushing (bushing) that reduces the loads, which caused the T/R cracking, on the T/R blades. This action would require installing the new bushing and re-identifying the T/R hub-and-grip and hub-and-blade assemblies and require a recurring inspection of each bushing. The proposed actions are intended to prevent fatigue failure of a T/R blade and subsequent loss of control of the helicopter.