Airworthiness Directive · Amendment 39-17259 · Tail rotor drive system
Eurocopter France Helicopters
This AD applies to Model SA.315B Alouette III, SE.3160 Alouette III, SA.316B Alouette III, SA.316C Alouette III, SA.319B Alouette III, SA 3180-ALOUETTE ASTAZOU, SA 318B-ALOUETTE ASTAZOU, and SA 318 C-ALOUETTE ASTAZOU helicopters with a free-wheel cage, part number (P/N) 3130S60-10-003 installed, certificated in any category.
We are adopting a new airworthiness directive (AD) for all Eurocopter France (Eurocopter) Model SA.315B Alouette III, SE.3160 Alouette III, SA.316B Alouette III, SA.316C Alouette III, SA.319B Alouette III, SA 3180-ALOUETTE ASTAZOU, SA 318B-ALOUETTE ASTAZOU, and SA 318 C-ALOUETTE ASTAZOU helicopters. This AD requires inspecting the cage of the free-wheel assembly for the correct alignment of the roller drive pocket recesses and replacing the free-wheel cage with an airworthy free-wheel cage if a defect exists. This AD was prompted by incorrect positioning of the roller drive pocket recesses on the tail rotor drive shaft free-wheel cage, which caused a pilot to experience a heavy jerk in the yaw control during in-flight autorotation training. The requirements of this AD are intended to prevent a loss of tail rotor drive 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 110 hours time-in-service:
(1) Remove the free-wheel assembly and pull out the free-wheel driven head.
(2) Inspect the free-wheel cage for correct alignment of the roller drive pocket recesses in accordance with Figure 2 of Eurocopter Alert Service Bulletin (ASB) No. SA315-65.48, Revision 0, or Eurocopter ASB No. ALOUETTE-65.149, Revision 0, both dated March 23, 2011, as appropriate for your model helicopter.
(3) If the right edge of the tab is in line with the right edge of the pocket recess, before further flight, replace the free-wheel cage with an airworthy free-wheel cage.
(4) Do not install an affected free-wheel assembly on any helicopter, unless the cage has passed inspection in accordance with paragraph (e)(2) through (e)(3) of this AD.
