AD 69-13-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12D | Airworthiness Directives; Fairchild Hiller Models UH-12D, UH-12E, UH-12E-L, UH-12L and UH-12L4 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12L | Airworthiness Directives; Fairchild Hiller Models UH-12D, UH-12E, UH-12E-L, UH-12L and UH-12L4 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12L4 | Airworthiness Directives; Fairchild Hiller Models UH-12D, UH-12E, UH-12E-L, UH-12L and UH-12L4 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E | Airworthiness Directives; Fairchild Hiller Models UH-12D, UH-12E, UH-12E-L, UH-12L and UH-12L4 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E-L | Airworthiness Directives; Fairchild Hiller Models UH-12D, UH-12E, UH-12E-L, UH-12L and UH-12L4 Helicopters |
Unsafe Condition
Failure of the attachment of collective yoke support brackets, P/N 31351 or 31483, to upper transmission housings, P/N 23541 or 23541-5, due to cracked Rosan inserts or insufficient bolt torque below 50 inch pounds.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 10 hours time in service after the effective date, inspect attachment bolts for torque and visually inspect Rosan inserts for cracks or damage. Replace damaged inserts and those with bolt torque less than 50 inch pounds before further flight. Within 100 hours' time in service, replace Rosan R206SB-8 inserts with RD206SB-8 inserts and install MS20073-04-7 bolts. For oversize R231SB-8 inserts, replace with RD231SB-8 inserts and RL-31-SB-9 locking rings.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 10 hours time in service after the effective date of this AD (for part (a)) and within the next 100 hours' time in service after the effective date (for part (b))
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Affected Aircraft
Fairchild Hiller Models UH-12D, UH-12E, UH-12E-L, UH-12L, and UH-12L4 helicopters certified in all categories.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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