Airworthiness Directive · Amendment 39-16434 · Turbomeca Arriel 1 Series Turboshaft Engines
Turbomeca Arriel 1 Series Turboshaft Engines
Superseded. A later AD replaced this one: AD 2011-26-02, AD 2010-19-06 R1. Comply with the one in force.
This AD applies to Turbomeca Arriel 1A, 1A1, 1B, 1C, 1C1, 1C2, 1D, 1D1, and 1S1 turboshaft engines that have incorporated Modification TU347. These engines are installed on, but not limited to, Eurocopter AS350 series, AS365 and SA365 series, Sikorsky S-76A series and S-76C series helicopters.
We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
Unless already done, do the following:
(1) For gas generator second stage turbine discs, part number (P/N) 0 292 25 040 0 that do not have the “CFR” marking, remove from service before exceeding 2,500 cycles-in-service (CIS) since-new or within 20 CIS from the effective date of this AD, whichever occurs later.
(2) For gas generator second stage turbine discs, P/N 0 292 25 040 0 that have the “CFR” marking, remove from service before exceeding 3,500 CIS since-new.
(3) After the effective date of this AD, for gas generator second stage turbine discs, P/N 0 292 25 040 0 that do not have the “CFR” marking, and have 2,500 or more CIS since-new, do not install into any engine.
(4) After the effective date of this AD, for gas generator second stage turbine discs, P/N 0 292 25 040 0 that have the “CFR” marking, and have 3,500 or more CIS since-new, do not install into any engine.
This AD differs from the Mandatory Continuing Airworthiness Information (MCAI) and/or service information as follows:
(1) European Aviation Safety Agency (EASA) AD 2010-0101R1, dated August 4, 2010, requires second stage turbine discs with fewer than 2,500 CIS to be removed upon accumulating 2,500 CIS.
(2) EASA AD 2010-0101R1, dated August 4, 2010, requires revising the approved aircraft maintenance program to reflect the new reduced life limit of 2,500 CIS.
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.
