Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for all Eurocopter Deutschland GmbH (ECD) Model MBB-BK117 C-2 helicopters with certain Generator Control Units (GCU) installed. This AD requires replacing the GCUs. This AD was prompted by reports of internal short circuits in certain GCUs. These actions are intended to prevent a short circuit, which could result in a loss of electrical generating power, loss of systems required for continued safe flight and landing, and subsequent loss of control of the helicopter.