Airworthiness Directives; Various Helicopters

The FAA is adopting a new airworthiness directive (AD) for various helicopters. This AD was prompted by a report of a loss of tail rotor authority due to auxiliary system fluid loss caused by a yaw pedal damper housing fatigue fracture and attachment bolt fatigue fracture. This AD requires performing repetitive visual inspections of the auxiliary servo assembly, a fluorescent penetrant inspection (FPI) of the yaw pedal damper housing and, if necessary, corrective actions. This AD also requires determining and recording the remaining life of a certain part and revising the existing rotorcraft flight manual (RFM) to provide the flight crew with procedures to follow under certain conditions. This AD also requires revising the airworthiness limitations section (ALS) of the existing maintenance manual (MM) or instructions for continued airworthiness (ICAs) and the existing approved maintenance or inspection program, as applicable by incorporating a new service life limit for a certain part. The FAA is issuing this AD to address the unsafe condition on these products.