AD 2021-17-18
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Aviat | Various | Airworthiness Directives; Leonardo S.p.a. Helicopters |
Unsafe Condition
cracking on the tail rotor (TR) mast, which could lead to failure of the TR mast, with consequent loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
an inspection of certain TR sleeve assemblies for discrepancies, an inspection of certain TR shaft assemblies for abnormal wear condition, corrosion, fretting, crack, and damage, a repetitive measurement of the position of the bushing of the TR sleeve assembly in relation to the pitch change slider assembly, and corrective actions if necessary, as specified in EASA AD 2021-0144.
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Compliance Time
within 25 hours time-in-service after the effective date of this AD
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Affected Aircraft
all Leonardo S.p.a. Model A109C, A109K2, A109E, A109S, and AW109SP helicopters.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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