AD FAA-2009-1124

We are adopting a new airworthiness directive (AD) for the specified Eurocopter France (Eurocopter) helicopters. This AD results from a mandatory continuing airworthiness information (MCAI) AD issued by the European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community. The MCAI Emergency AD states that there has been a report of the failure of a flexible coupling on one of the main gearbox (MGB) inputs, which may be the result of loss of the tightening torque load, or insufficient tightening of the nuts on the bolts fixing the discs of the flexible coupling to its sliding and fixed hinges. This condition, if not corrected, could result in failure of the coupling discs, and if this condition develops on both the left-hand (LH) and right-hand (RH) MGB inputs, a complete loss of power to the transmission and subsequent loss of control of the helicopter.