AD Amdt-39-9252
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller | Various | Airworthiness Directives; Hiller Aircraft Corporation Model UH- 12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
Unsafe Condition
Failure of the outboard tension-torsion (T-T) bar pin due to cracks in the head area, which could result in loss of in-plane stability of the main rotor blade and subsequent loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Perform a dye-penetrant inspection of the head of the main rotor outboard T-T bar pin for cracks; conduct a visual inspection of the outboard T-T bar pin for proper alignment and adjust if necessary; install shims at the inboard end of the drag strut.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
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Affected Aircraft
Hiller Aircraft Corporation Model UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E 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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