AD 2011-13-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Aviat | Various | Airworthiness Directives; Turbomeca S.A. ARRIEL 2B and 2B1 Turboshaft Engines |
| engine | Turbomeca | S | Airworthiness Directives; Turbomeca S.A. ARRIEL 2B and 2B1 Turboshaft Engines |
Unsafe Condition
Several cases of Gas Generator (GG) Turbine Blade rupture occurred in service on ARRIEL 2 twin engine applications and recently one on a single engine helicopter. Rupture of a GG turbine blade could result in an uncommanded in-flight shutdown and an emergency autorotation landing or accident.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Accomplish TU166 modification in accordance with Turbomeca Mandatory Service Bulletin (MSB) A292 72 3166 Version B, dated September 20, 2010, when the GG Turbine is replaced, during engine or Module M03 overhaul or repair, or within 1,300 cycles-in-service after the effective date of this AD, whichever occurs first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 1,300 cycles-in-service after the effective date of this AD.
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Affected Aircraft
Turbomeca S.A. ARRIEL 2B and 2B1 turboshaft engines not modified by TU166 modification, installed on, but not limited to, Eurocopter AS 350 B3 and EC 130 B4 helicopters.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
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