Airworthiness Directive · Amendment 39-17261 · Dc generator control unit
Eurocopter Deutschland Helicopters
This AD applies to Model MBB-BK117 C-2 helicopters with a generator control unit (GCU), part number (P/N) 51530-021EI with no modification (MOD), MOD A, or MOD B installed, certificated in any category.
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.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(1) Within the next 300 hours time-in-service or 6 months, whichever occurs first, replace all GCUs with no MOD, MOD A, or MOD B with an airworthy GCU.
(2) Do not install a GCU P/N 51530-021-EI with no MOD, MOD A, or MOD B on any helicopter.
