AD 73-20-03
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12 | Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12A | Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12B | Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12C | Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12D | Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E | Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E-L | Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters |
Unsafe Condition
Cracks in the main rotor hub parts numbered 51437, 51437-6, 51437-7, 51437-8, 51437-9, 51437-11, 51437-901, and 51437-11-911 in the area opposite the control rotor trunnion attachments.
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Required Actions
Conduct dye penetrant inspection of the main rotor hubs with specified part numbers inside the hub in the area opposite the control rotor trunnion attachments. Replace cracked hubs with new parts before further flight and continue 50-hour interval inspections. Report cracks found including model, serial number, and total time in service to the FAA.
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Compliance Time
within the next 5 hours time in service after the effective date of this AD, unless already accomplished on receipt of the airmail AD dated September 6, 1973, and thereafter at intervals not to exceed 50 hours time in service from the last inspection
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Affected Aircraft
Hiller Aviation and Siam Hiller Holdings, Inc. Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E 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 Hub
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_73-20-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-20-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters Subject: Main Rotor Hub Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/30/1973 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12 | UH-12A | UH-12B | UH-12C | UH-12D | 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 73-20-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1724 AD NUMBER: 73-20-03 SUBJECT HEADING: Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters ACTION: SUMMARY: DATES: Effective October 30, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-20-03 HILLER AVIATION: Amdt. 39-1724. Applies to Hiller Model UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters certificated in all categories. Compliance required within the next 5 hours time in service after the effective date of this AD, unless already accomplished on receipt of the airmail AD dated September 6, 1973, and thereafter at intervals not to exceed 50 hours time in service from the last inspection. To detect cracks in the main rotor hub P/N's 51437, 51437-6, 51437-7, 51437-8, 51437- 9, 51437-11, 51437-901, and 51437-11-911, accomplish the following: Conduct dye penetrant inspection of the main rotor hubs P/N's 51437, 51437-6, 51437-7, 51437-8, 51437-9, 51437-11, 51437-901, 51437-11-911, inside the hub in the area opposite the control rotor trunnion attachments. If cracks are found, replace with a new part before further flight and continue the 50 hour interval dye penetrant inspections. Report cracks found, model and serial number, and total time in service on the main rotor hub, to Chief, Aircraft Engineering Division, Federal Aviation Administration, Western Region, P.O. Box 92007, Worldway Postal Center, Los Angeles, California 90009. (Reporting approved by the Bureau of the Budget under B.O.B. No. 04-R0174). This amendment is effective on October 30, 1973. FOOTER:
Document Text
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AD Final Rules - DRS_73-20-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-20-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters Subject: Main Rotor Hub Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/30/1973 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12 | UH-12A | UH-12B | UH-12C | UH-12D | 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 73-20-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1724 AD NUMBER: 73-20-03 SUBJECT HEADING: Airworthiness Directives; Hiller Models UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters ACTION: SUMMARY: DATES: Effective October 30, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-20-03 HILLER AVIATION: Amdt. 39-1724. Applies to Hiller Model UH-12, UH-12A, UH-12B, UH-12C, UH-12D, and UH-12E Helicopters certificated in all categories. Compliance required within the next 5 hours time in service after the effective date of this AD, unless already accomplished on receipt of the airmail AD dated September 6, 1973, and thereafter at intervals not to exceed 50 hours time in service from the last inspection. To detect cracks in the main rotor hub P/N's 51437, 51437-6, 51437-7, 51437-8, 51437- 9, 51437-11, 51437-901, and 51437-11-911, accomplish the following: Conduct dye penetrant inspection of the main rotor hubs P/N's 51437, 51437-6, 51437-7, 51437-8, 51437-9, 51437-11, 51437-901, 51437-11-911, inside the hub in the area opposite the control rotor trunnion attachments. If cracks are found, replace with a new part before further flight and continue the 50 hour interval dye penetrant inspections. Report cracks found, model and serial number, and total time in service on the main rotor hub, to Chief, Aircraft Engineering Division, Federal Aviation Administration, Western Region, P.O. Box 92007, Worldway Postal Center, Los Angeles, California 90009. (Reporting approved by the Bureau of the Budget under B.O.B. No. 04-R0174). This amendment is effective on October 30, 1973. FOOTER:
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