AD FAA-2014-0478

We are publishing a new airworthiness directive (AD) for certain AgustaWestland S.p.A. Model AB139 and AW139 helicopters. This AD requires repetitively inspecting the Main Rotor (M/R) Rotating Scissors for play of the Lower Half Scissor Spherical Bearing (bearing) and removing the bearing if there is play beyond allowable limits. This AD also requires removing all affected bearings. This AD is prompted by reports of certain bearings dislodging from certain M/R Rotating Scissors. These actions are intended to detect excessive play of the bearing and prevent failure of the M/R Rotating Scissors and subsequent loss of control of the helicopter.