Airworthiness Directives; Aerospatiale Model ATR42 and ATR72 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all Aerospatiale Model ATR42 and ATR72 series airplanes, that requires replacement of the attachment clips on the wing-to- fuselage fairings and on the upper cowlings of the engine nacelle with new improved attachment clips, and adding cup washers on the wing-to- fuselage fairing panels on certain airplanes. This amendment also requires a one-time inspection of certain fairings and the upper cowlings of the engine nacelle to detect discrepancies of the attachment hardware and the fairing panel; and replacement of the panel with a serviceable panel, if necessary. This amendment is prompted by a report of deformed attachment clips found on the wing-to-fuselage fairings and on the upper cowlings of the engine nacelle, and by a report of severe inflight vibration due to a loose wing/body fairing panel. The actions specified by this AD are intended to prevent deformation of the attachment clips due to insufficient strength of the attachment clip material. Such deformation of the attachment clips could result in the fairings and cowlings detaching from the airplane during flight and subsequently causing damage to the empennage or posing a hazard to persons or property on the ground.