Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

We are superseding an existing airworthiness directive (AD) for all Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters. That AD currently requires revising the "Emergency and Malfunction Procedures" and "Performance Data" sections of the Rotorcraft Flight Manual (RFM) by inserting three temporary pages into the RFM to alert pilots to monitor the power display when a generator is deactivated and provides procedures to prevent failure of the remaining generator. Before we issued that AD, the manufacturer developed a procedure to modify the two "After Junction Boxes" by removing a diode from each box, which provides terminating action for our AD requirements. These actions are intended to require implementing this terminating action to prevent an electrical power system failure and subsequent loss of control of the helicopter and revising the RFM accordingly, by removing the temporary pages inserted to comply with the superseded AD.