Airworthiness Directives; Eurocopter France Model SE3160, SA315B, SA316B, SA316C, and SA319B Helicopters

This amendment supersedes an existing airworthiness directive (AD) for the specified Eurocopter France (Eurocopter) model helicopters. The existing AD requires certain inspections of a main rotor blade (blade) manufactured under a Parts Manufacturer Approval under Supplemental Type Certificate (STC) SH778GL. The AD requires inspecting each affected root end bolt (bolt) and bolt-hole for corrosion or a crack on the blade root end fitting (fitting) or in a bolt-hole. For certain serial-numbered blades, the AD also requires a one-time pull test on each fitting and blade root end doubler (doubler) to detect disbonding. This AD requires certain inspections for voids in any doubler or fitting and for paint cracks along the forward and aft edge of the blade fitting. Also, this AD requires inspecting the blade tip weight housing attachment. This AD also requires replacing unairworthy blades with airworthy blades. This amendment is prompted by reports from the STC holder of disbonds at the fittings, doublers, and the tip weight fitting. The actions specified by this AD are intended to prevent blade failure and subsequent loss of control of the helicopter.