Airworthiness Directive · Amendment 39-15469 · Turbomeca Makila 1A and 1A1 Turboshaft Engines
Turbomeca Makila 1A and 1A1 Turboshaft Engines
This AD applies to Turbomeca Makila 1A and 1A1 turboshaft engines. These engines are installed on, but not limited to, Eurocopter France model AS 332C, AS 332L, and AS 332L1 helicopters.
The FAA is superseding an existing airworthiness directive (AD) for Turbomeca Makila 1A, 1A1, and 1A2 turboshaft engines. That AD currently requires replacing certain digital electronic control units (DECUs) and electronic control units (ECUs) with modified DECUs and ECUs. This AD applies only to Makila 1A and 1A1 turboshaft engines, and requires replacing the selector-comparator board in the ECU with a board incorporating Turbomeca modification TU 250. This AD results from recent unexplained reversions of the ECU to the 65% N1 back-up mode. We are issuing this AD to prevent dual-engine continued operation at 65% N1 after reversion of the ECU to the 65% N1 back-up mode due to temporary loss of N2 speed signal, which could lead to inability to continue safe flight, emergency autorotation landing, or an accident.
You are responsible for having the actions required by this AD performed before June 30, 2008, unless the actions have already been done.
(f) Replace the selector-comparator board in the ECU with a board incorporating Turbomeca Modification TU 250. Information on Modification TU 250 can be found in Turbomeca Mandatory Service Bulletin No. 298 73 0250, dated March 23, 2007.
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.
