AD FAA-2013-0307

We are adopting an airworthiness directive (AD) for Eurocopter France (Eurocopter) Model AS332C, AS332L, and AS332L1 helicopters and superseding an AD for Model AS332L2 and EC225LP helicopters. This AD requires inspecting the chip detector and modifying the chip collector, both installed on the main gearbox (MGB). This AD is prompted by an investigation which showed a failure within the epicyclic reduction gear module (epicyclic module) resulted in the rupture of the MGB case and separation of the main rotor head of a Model AS332L2 helicopter. These actions are intended to prevent failure of the MGB and subsequent loss of control of the helicopter.