Airworthiness Directive · Amendment 39-17352 · Tail rotor drive shaft
Eurocopter Deutschland GmbH Helicopters
This AD applies to Model MBB-BK 117 C-2 helicopters, with long tail rotor drive shaft assembly part number B651M1002101 or B651M1002102 installed, certificated in any category.
We are adopting a new airworthiness directive (AD) for Eurocopter Deutschland GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This AD requires inspecting the long tail rotor drive shaft assembly for blind rivets, and if any blind rivets are installed, replacing that shaft assembly. This AD was prompted by the discovery that some helicopters have blind rivets installed in the place of solid rivets in the long tail rotor drive shaft. The actions of this AD are intended to detect blind rivets installed in the long tail rotor drive shaft, which could lead to failure of the tail rotor drive shaft 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.
Within 100 hours time-in-service, inspect the long tail rotor drive shaft assembly for blind rivets as indicated in sections A-A and B-B of Figure 1 of Eurocopter Alert Service Bulletin No. MBB BK117 C-2-65A-003, dated May 4, 2009 (ASB).
(1) If there are no blind rivets installed on the shaft assembly, no further action is required by this AD.
(2) If there is one or more blind rivets installed on the shaft assembly in the areas depicted in Figure 1 of the ASB, before further flight, replace the shaft assembly of the long tail rotor drive shaft with an airworthy shaft assembly that does not have blind rivets installed.
(3) After the effective date of this AD, do not install a tail rotor drive shaft assembly that has blind rivets installed.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
