AD FAA-2014-0971

We are superseding Airworthiness Directive (AD) 2014-07-51 for AgustaWestland S.p.A. Model AB139 and AW139 helicopters with certain main rotor (M/R) rotating scissors installed. AD 2014-07-51 required repetitively inspecting the M/R rotating scissors for play of the lower half scissor spherical bearing (bearing) and removing the bearing if there was play beyond allowable limits. AD 2014-07-51 also required removing all affected bearings. AD 2014-07-51 was prompted by reports of certain bearings dislodging from certain M/R rotating scissors. This new AD retains the requirements of AD 2014-07-51, expands the applicability, and requires installing a special nut. 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.