AD 81-04-01
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12D | Airworthiness Directives; HILLER AIRCRAFT Models UH-12D, UH-12E, OH-23G, UH-12L Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12L | Airworthiness Directives; HILLER AIRCRAFT Models UH-12D, UH-12E, OH-23G, UH-12L Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E | Airworthiness Directives; HILLER AIRCRAFT Models UH-12D, UH-12E, OH-23G, UH-12L Helicopters |
Unsafe Condition
Rudder balance cables (P/N HS 1053-2) may fray and break due to non-conformance with the type design requiring 7 x 19 cable.
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Required Actions
Perform a one-time visual inspection of the rudder balance cable assembly per Hiller Service Bulletin No. 32-2 Part II, Subparts A and B. Remove non-conforming rudder cable assemblies (P/N HS 1053-2) from service. Use special flight permits under FAR 21.197/21.199 to relocate aircraft for AD compliance.
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Compliance Time
within ten (10) calendar days from the effective date of this AD
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Affected Aircraft
Hiller Aircraft Models UH-12D, UH-12E, OH-23G, UH-12L, and all models converted to turbine power via STC 177WE or STC 178WE
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Federal Register Abstract
Rudder Cable Assembly
Applicability Source Text
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AD Final Rules - DRS_81-04-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-04-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; HILLER AIRCRAFT Models UH-12D, UH-12E, OH-23G, UH-12L Helicopters Subject: Rudder Cable Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/09/1981 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12D | UH-12L | UH-12E Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 81-04-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4034 AD NUMBER: 81-04-01 SUBJECT HEADING: Airworthiness Directives; HILLER AIRCRAFT Models UH-12D, UH-12E, OH-23G, UH-12L Helicopters ACTION: SUMMARY: DATES: Effective February 9, 1981. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-04-01 HILLER AIRCRAFT: Amendment 39-4034. Applies to Models UH-12D, UH-12E, OH-23G, UH-12L, and all models converted to turbine power in accordance with Supplementary Type Certificate STC 177WE or STC 178WE, certified in all categories. Compliance required within ten (10) calendar days from the effective date of this AD, unless already accomplished. To prevent rudder balance cables from fraying and breaking, accomplish the following: (a) Perform a one time visual inspection of the rudder balance cable assembly, P/N HS 1053-2, in accordance with Hiller Service Bulletin No. 32-2 Part II, Accomplishment Instructions, Subparts A and B, dated December 31, 1980. (b) Remove from service the rudder cable assemblies, P/N HS 1053-2, which do not conform to type design. Type design is 7 x 19 cable. The Hiller Service Bulletin No. 32-2 depicts the acceptable cable. (c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes or helicopters to a base for the accomplishment of inspections or modifications required by this AD. (d) Alternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Engineering and Manufacturing Branch, FAA Western Region. This amendment becomes effective February 9, 1981. FOOTER:
Document Text
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AD Final Rules - DRS_81-04-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-04-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; HILLER AIRCRAFT Models UH-12D, UH-12E, OH-23G, UH-12L Helicopters Subject: Rudder Cable Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/09/1981 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12D | UH-12L | UH-12E 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: 81-04-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4034 AD NUMBER: 81-04-01 SUBJECT HEADING: Airworthiness Directives; HILLER AIRCRAFT Models UH-12D, UH-12E, OH-23G, UH-12L Helicopters ACTION: SUMMARY: DATES: Effective February 9, 1981. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-04-01 HILLER AIRCRAFT: Amendment 39-4034. Applies to Models UH-12D, UH-12E, OH-23G, UH-12L, and all models converted to turbine power in accordance with Supplementary Type Certificate STC 177WE or STC 178WE, certified in all categories. Compliance required within ten (10) calendar days from the effective date of this AD, unless already accomplished. To prevent rudder balance cables from fraying and breaking, accomplish the following: (a) Perform a one time visual inspection of the rudder balance cable assembly, P/N HS 1053-2, in accordance with Hiller Service Bulletin No. 32-2 Part II, Accomplishment Instructions, Subparts A and B, dated December 31, 1980. (b) Remove from service the rudder cable assemblies, P/N HS 1053-2, which do not conform to type design. Type design is 7 x 19 cable. The Hiller Service Bulletin No. 32-2 depicts the acceptable cable. (c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes or helicopters to a base for the accomplishment of inspections or modifications required by this AD. (d) Alternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Engineering and Manufacturing Branch, FAA Western Region. This amendment becomes effective February 9, 1981. FOOTER:
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