AD 71-25-08
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12 | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12A | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12B | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12C | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12D | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12L | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12L4 | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E-L | Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters |
Unsafe Condition
Cracks in main rotor blade part number 53100 could result in blade failure.
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Required Actions
Inspect main rotor blade P/N 53100 for cracks using dye penetrant within 10 hours time in service after the effective date. Remove defective blades from service prior to further flight and report serial numbers to the specified FAA office.
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Compliance Time
within 10 hours time in service after the effective date
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Affected Aircraft
Fairchild Hiller Model UH-12 helicopters certificated in all categories, including models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, UH-12L, UH-12L4, UH-12E, and UH-12E-L.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Inspect Main Rotor Blades
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_71-25-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-25-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters Subject: Inspect Main Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/14/1971 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12 | UH-12A | UH-12B | UH-12C | UH-12D | UH-12L | UH-12L4 | UH-12E | UH-12E-L Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 71-25-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1356 AD NUMBER: 71-25-08 SUBJECT HEADING: Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters ACTION: SUMMARY: DATES: Effective December 14, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-25-08 FAIRCHILD HILLER ROTORCRAFT: Amdt. 39-1356. Applies to Fairchild Hiller UH-12 helicopters certificated in all categories. Compliance required as indicated. Following an immediate visual inspection and within 10 hours time in service after the effective date of this airworthiness directive inspect main rotor blade P/N 53100 for cracks, using dye penetrant. Any blades found defective are to be removed from service prior to further flight and S/Ns reported to Engineering and Manufacturing Branch, Federal Aviation Administration, Eastern Region, JFK International Airport, Jamaica, New York 11430. Approval of this reporting procedure has been obtained from the Bureau of Budget in accordance with Federal Reports Act. Reporting approved by Bureau of Budget under BOB Number 04-R0174. This amendment is effective December 14, 1971 and was effective upon receipt by owners and operators of the letter dated November 9, 1971 which contained this amendment. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_71-25-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-25-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters Subject: Inspect Main Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/14/1971 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12 | UH-12A | UH-12B | UH-12C | UH-12D | UH-12L | UH-12L4 | UH-12E | UH-12E-L Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 71-25-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1356 AD NUMBER: 71-25-08 SUBJECT HEADING: Airworthiness Directives; Fairchild Hiller Model UH-12 Helicopters ACTION: SUMMARY: DATES: Effective December 14, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-25-08 FAIRCHILD HILLER ROTORCRAFT: Amdt. 39-1356. Applies to Fairchild Hiller UH-12 helicopters certificated in all categories. Compliance required as indicated. Following an immediate visual inspection and within 10 hours time in service after the effective date of this airworthiness directive inspect main rotor blade P/N 53100 for cracks, using dye penetrant. Any blades found defective are to be removed from service prior to further flight and S/Ns reported to Engineering and Manufacturing Branch, Federal Aviation Administration, Eastern Region, JFK International Airport, Jamaica, New York 11430. Approval of this reporting procedure has been obtained from the Bureau of Budget in accordance with Federal Reports Act. Reporting approved by Bureau of Budget under BOB Number 04-R0174. This amendment is effective December 14, 1971 and was effective upon receipt by owners and operators of the letter dated November 9, 1971 which contained this amendment. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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