Summary
The FAA proposes to supersede Airworthiness Directive (AD) 2017-23-08 for Agusta S.p.A. (now Leonardo S.p.a.) Model AB139 and AW139 helicopters. AD 2017-23-08 requires repetitively inspecting the main rotor (M/R) rotating scissors, removing certain lower half scissor spherical bearings (bearings) from service, replacing the removed bearings with a new bearing, and installing a special nut. Since the FAA issued AD 2017-23-08, investigation results determined that a quality control issue may have affected the production of the affected bearings. This proposed AD would retain the requirements of AD 2017-23- 08 and require replacing each affected bearing with a certain part- numbered bearing. The actions of this proposed AD are intended to address an unsafe condition on these products.