AD FAA-2019-0641

The FAA is superseding Airworthiness Directive (AD) 2018-18-12 for Airbus Helicopters (Airbus) Model AS350B, AS350B1, AS350B2, AS350B3, and AS350BA helicopters with a certain part-numbered Pall Aerospace Corporation Inlet Barrier Filter (IBF) element installed. AD 2018-18-12 required revising the Rotorcraft Flight Manual Supplement (RFMS) for your helicopter to prohibit operating a helicopter with an IBF element in wet weather and drying or replacing the IBF element if wet. This AD retains the requirements of AD 2018-18-12 but no longer allows reinstallation of a filter after it has been removed. This AD also expands the applicability, provides an optional terminating action for the RFMS revision for your helicopter, and prohibits installing the affected IBFs on any helicopter. This AD was prompted by further review of the unsafe condition and the determination that additional part- numbered IBF elements are affected by the unsafe condition. The actions of this AD are intended to address an unsafe condition on these products.