AD 86-17-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12D | Airworthiness Directives; ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series and Military OH-23F and OH-23G Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E | Airworthiness Directives; ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series and Military OH-23F and OH-23G Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E-L | Airworthiness Directives; ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series and Military OH-23F and OH-23G Helicopters |
Unsafe Condition
Cracks and failures in the main rotor blade fork P/N 52110-3 at the outboard tension-torsion bar retention bolt hole.
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Required Actions
Verify each installed P/N 52110-3 fork has a serial number displayed; perform daily visual checks for cracks; conduct dye penetrant inspections every 100 hours' time in service, with initial inspections within 10 hours' time in service for forks with 240+ hours and prior to 250 hours' time in service for those with less. Replace cracked forks before flight.
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Compliance Time
Within the next 10 hours' time in service after the effective date, and recurring intervals as specified.
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Affected Aircraft
ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series, Military OH-23F and OH-23G helicopters, including those converted under STC SH177WE and SH178WE, equipped with main rotor blade fork P/N 52110-3.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Blade Fork
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_86-17-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-17-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series and Military OH-...Show more Subject: Main Rotor Blade Fork Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/22/1986 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: 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: This AD also supersedes 60-07-05, 63-12-01, and 79-07-01. AIRWORTHINESS DIRECTIVES FINAL RULES: 86-17-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5367 AD NUMBER: 86-17-02 SUBJECT HEADING: Airworthiness Directives; ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series and Military OH-23F and OH-23G Helicopters ACTION: SUMMARY: DATES: Effective August 22, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-17-02 ROGERSON HILLER CORP.: Amendment 39-5367. Applies to Model UH-12D, UH-12E, and UH-12E4 series helicopters, including military Models OH-23F and OH-23G, and all those converted in accordance with STC's SH177WE and SH178WE, certificated in any category, equipped with main rotor blade fork P/N 52110-3. Compliance is required as indicated, unless already accomplished. To detect cracks and prevent failures which have occurred in the main rotor blade fork P/N 52110-3 at the outboard tension-torsion bar retention bolt hole, accomplish the following: (a) Within the next 10 hours' time in service after the effective date of this AD, verify that each installed P/N 52110-3 fork has a serial number permanently displayed on its outer surface. Remove from service forks found not to be serialized and replace with serialized parts. (b) Perform a daily visual check of P/N 52110-3 forks for cracks in the area of the outboard tension-torsion bar retention bolt hole. Washers and nuts need not be removed for this inspection. This check may be performed by the pilot. NOTE: For the requirements regarding the listing of compliance and method of compliance with this AD in the aircraft's permanent maintenance record, see section 91.173. (c) On forks having 240 or more hours' time in service on the effective date of this AD, within the next 10 hours' time in service, unless already accomplished within the last 90 hours' time in service, and within each 100 hours' time in service thereafter from the last inspection, accomplish the inspection specified in (e). (d) On forks having less than 240 hours' time in service on the effective date of this AD, accomplish the inspection specified in (e) prior to the accumulation of 250 hours' time in service and within each 100 hours' time in service thereafter from the last inspection. (e) Perform a dye penetrant inspection, or FAA-approved equivalent, of the bolt hole and adjacent milled surfaces. For this inspection, remove the nut, washer, and pin. (f) Replace cracked rotor forks with like serviceable parts prior to further flight. (g) Special flight permits may be issued in accordance with sections 21.197 and 21.199 to operate aircraft to a base for the accomplishment of inspections required by this AD. (h) An alternate method of compliance which provides an equivalent level of safety may be approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. This amendment supersedes Amendment 39-3540 (44 FR 50035), AD 79-18-04. This amendment becomes effective August 22, 1986. FOOTER:
Document Text
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AD Final Rules - DRS_86-17-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-17-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series and Military OH-...Show more Subject: Main Rotor Blade Fork Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/22/1986 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: 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: This AD also supersedes 60-07-05, 63-12-01, and 79-07-01. AIRWORTHINESS DIRECTIVES FINAL RULES: 86-17-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5367 AD NUMBER: 86-17-02 SUBJECT HEADING: Airworthiness Directives; ROGERSON HILLER CORP Model UH-12D, UH-12E, UH-12E4 Series and Military OH-23F and OH-23G Helicopters ACTION: SUMMARY: DATES: Effective August 22, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-17-02 ROGERSON HILLER CORP.: Amendment 39-5367. Applies to Model UH-12D, UH-12E, and UH-12E4 series helicopters, including military Models OH-23F and OH-23G, and all those converted in accordance with STC's SH177WE and SH178WE, certificated in any category, equipped with main rotor blade fork P/N 52110-3. Compliance is required as indicated, unless already accomplished. To detect cracks and prevent failures which have occurred in the main rotor blade fork P/N 52110-3 at the outboard tension-torsion bar retention bolt hole, accomplish the following: (a) Within the next 10 hours' time in service after the effective date of this AD, verify that each installed P/N 52110-3 fork has a serial number permanently displayed on its outer surface. Remove from service forks found not to be serialized and replace with serialized parts. (b) Perform a daily visual check of P/N 52110-3 forks for cracks in the area of the outboard tension-torsion bar retention bolt hole. Washers and nuts need not be removed for this inspection. This check may be performed by the pilot. NOTE: For the requirements regarding the listing of compliance and method of compliance with this AD in the aircraft's permanent maintenance record, see section 91.173. (c) On forks having 240 or more hours' time in service on the effective date of this AD, within the next 10 hours' time in service, unless already accomplished within the last 90 hours' time in service, and within each 100 hours' time in service thereafter from the last inspection, accomplish the inspection specified in (e). (d) On forks having less than 240 hours' time in service on the effective date of this AD, accomplish the inspection specified in (e) prior to the accumulation of 250 hours' time in service and within each 100 hours' time in service thereafter from the last inspection. (e) Perform a dye penetrant inspection, or FAA-approved equivalent, of the bolt hole and adjacent milled surfaces. For this inspection, remove the nut, washer, and pin. (f) Replace cracked rotor forks with like serviceable parts prior to further flight. (g) Special flight permits may be issued in accordance with sections 21.197 and 21.199 to operate aircraft to a base for the accomplishment of inspections required by this AD. (h) An alternate method of compliance which provides an equivalent level of safety may be approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. This amendment supersedes Amendment 39-3540 (44 FR 50035), AD 79-18-04. This amendment becomes effective August 22, 1986. FOOTER:
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