AD 72-13-08
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12L | Airworthiness Directives: Fairchild Hiller Models UH-12L, UH-12L4 and UH-12E-L Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12L4 | Airworthiness Directives: Fairchild Hiller Models UH-12L, UH-12L4 and UH-12E-L Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E-L | Airworthiness Directives: Fairchild Hiller Models UH-12L, UH-12L4 and UH-12E-L Helicopters |
Unsafe Condition
Main rotor blades P/N 53100-01 with specific serial numbers (5, 21, 29, 66, 71, 74, 88, 125, 129, 130, 132, 142, 143, 158, 159, 160, 161, 162, 171, 176) may fail, resulting in loss of control.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove and replace listed main rotor blades with non-listed serial numbers. Inspect and alter all other main rotor blades per Service Bulletin SBUH12L-51-1 or approved method within specified timeframes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 10 hours in service after effective date (October 19, 1972) for removal and replacement. Within 30 hours time in service after effective date for inspection and alteration.
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Affected Aircraft
Fairchild Hiller Models UH-12L, UH-12L4, and UH-12E-L helicopters certificated in all categories.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Blades
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_72-13-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-13-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives: Fairchild Hiller Models UH-12L, UH-12L4 and UH-12E-L Helicopters Subject: Main Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/19/1972 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12L | UH-12L4 | UH-12E-L Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 72-13-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1539 AD NUMBER: 72-13-08 SUBJECT HEADING: Airworthiness Directives: Fairchild Hiller Models UH-12L, UH-12L4 and UH-12E-L Helicopters ACTION: SUMMARY: DATES: Effective October 19, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-13-08 FAIRCHILD-HILLER: Amendment 39-1471 as amended by Amendment 39-1539. Applies to Fairchild Hiller UH-12L, UH-12L4, and UH-12E-L helicopters certificated in all categories. 1. Within 10 hours in service after effective date of this airworthiness directive remove from service P/N 53100-01 main rotor blades S/N's 5, 21, 29, 66, 71, 74, 88, 125, 129, 130, 132, 142, 143, 158, 159, 160, 161, 162, 171, and 176, and replace with blades P/N 53100-01 with S/N's other than those listed. 2. Within 30 hours time in service after the effective date of this airworthiness directive, inspect and alter all other main rotor blades in accordance with Fairchild Hiller Service Bulletin SBUH12L-51-1, 7/31/72, Para. 2A thru 2K, or equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. Amendment 39-1539 was effective June 27, 1972, and was effective for all recipients of the air mail notice dated May 11, 1972 which contained this airworthiness directive. This amendment 39-1539 is effective October 19, 1972. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_72-13-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-13-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives: Fairchild Hiller Models UH-12L, UH-12L4 and UH-12E-L Helicopters Subject: Main Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/19/1972 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12L | UH-12L4 | 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 72-13-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1539 AD NUMBER: 72-13-08 SUBJECT HEADING: Airworthiness Directives: Fairchild Hiller Models UH-12L, UH-12L4 and UH-12E-L Helicopters ACTION: SUMMARY: DATES: Effective October 19, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-13-08 FAIRCHILD-HILLER: Amendment 39-1471 as amended by Amendment 39-1539. Applies to Fairchild Hiller UH-12L, UH-12L4, and UH-12E-L helicopters certificated in all categories. 1. Within 10 hours in service after effective date of this airworthiness directive remove from service P/N 53100-01 main rotor blades S/N's 5, 21, 29, 66, 71, 74, 88, 125, 129, 130, 132, 142, 143, 158, 159, 160, 161, 162, 171, and 176, and replace with blades P/N 53100-01 with S/N's other than those listed. 2. Within 30 hours time in service after the effective date of this airworthiness directive, inspect and alter all other main rotor blades in accordance with Fairchild Hiller Service Bulletin SBUH12L-51-1, 7/31/72, Para. 2A thru 2K, or equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. Amendment 39-1539 was effective June 27, 1972, and was effective for all recipients of the air mail notice dated May 11, 1972 which contained this airworthiness directive. This amendment 39-1539 is effective October 19, 1972. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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