AD 89-07-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-76A | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-76B | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76 Series Helicopters |
Unsafe Condition
Fatigue failure of the tail rotor component could result in a reduction of directional control and hazardous tail rotor vibration in the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the tail rotor horn, P/N 76101-05006, with a serviceable one before it accumulates 12,000 hours' time in service. Initial replacement must occur within 100 hours' time in service after the AD's effective date or before 12,000 hours' time in service, whichever is later. Use tail rotor blade bonded assembly hours if component records are unavailable.
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Compliance Time
Within the next 100 hours' time in service after the effective date of this AD or before the accumulation of 12,000 hours' time in service, whichever occurs later
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Affected Aircraft
Sikorsky Aircraft Corporation Model S-76A and S-76B helicopters equipped with tail rotor horn P/N 76101-05006.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Tail Rotor Horn
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_89-07-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-07-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76 Series Helicopters Subject: Tail Rotor Horn Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/27/1989 Make: Sikorsky Aircraft Corporation Model: S-76A | S-76B Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185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: 89-07-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-6171 AD NUMBER: 89-07-12 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76 Series Helicopters ACTION: SUMMARY: DATES: Effective April 27, 1989. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-07-12 SIKORSKY AIRCRAFT: Amendment 39-6171. Applicability: Model S-76 series helicopters, certificated in any category, that are equipped with tail rotor horn, P/N 76101-05006. Compliance: Required as indicated, unless already accomplished. To prevent possible fatigue failure of the tail rotor component, which could result in a reduction of directional control and hazardous tail rotor vibration in the helicopter, accomplish the following: (a) Within the next 100 hours' time in service after the effective date of this AD or before the accumulation of 12,000 hours time in service, whichever occurs later, replace the tail rotor horn, P/N 76101-05006, with a serviceable tail rotor horn that has not exceeded 12,000 hours' time in service. Thereafter, replace the tail rotor horn P/N 76101-05006, with a serviceable tail rotor horn before the accumulation of 12,000 hours' time in service. (b) Operators who have not kept records of hours' time in service on individual tail rotor horn component parts must substitute the hours' time in service of the tail rotor blade bonded assembly, P/N 76101-05020 or P/N 76088-20077. (c) For purposes of complying with this AD, the hours' time in service for the individual tail rotor horn and blade components that were not installed at the time of issuance of the initial rotorcraft airworthiness certificate must be determined from rotorcraft records. (d) Upon request, an alternate means of compliance which provides a level of safety equivalent to the requirements of this AD may be used when approved by the Manager, Boston Aircraft Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone (617) 273-7118. (e) Upon submission of substantiating data by an owner or operator through an FAA Aviation Safety Inspector, the Manager, Boston Aircraft Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone (617) 273-7118, may adjust the compliance time specified in this AD. This amendment (39-6171, AD 89-07-12) becomes effective on April 27, 1989. FOOTER:
Document Text
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AD Final Rules - DRS_89-07-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-07-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76 Series Helicopters Subject: Tail Rotor Horn Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/27/1989 Make: Sikorsky Aircraft Corporation Model: S-76A | S-76B 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: 89-07-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-6171 AD NUMBER: 89-07-12 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76 Series Helicopters ACTION: SUMMARY: DATES: Effective April 27, 1989. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-07-12 SIKORSKY AIRCRAFT: Amendment 39-6171. Applicability: Model S-76 series helicopters, certificated in any category, that are equipped with tail rotor horn, P/N 76101-05006. Compliance: Required as indicated, unless already accomplished. To prevent possible fatigue failure of the tail rotor component, which could result in a reduction of directional control and hazardous tail rotor vibration in the helicopter, accomplish the following: (a) Within the next 100 hours' time in service after the effective date of this AD or before the accumulation of 12,000 hours time in service, whichever occurs later, replace the tail rotor horn, P/N 76101-05006, with a serviceable tail rotor horn that has not exceeded 12,000 hours' time in service. Thereafter, replace the tail rotor horn P/N 76101-05006, with a serviceable tail rotor horn before the accumulation of 12,000 hours' time in service. (b) Operators who have not kept records of hours' time in service on individual tail rotor horn component parts must substitute the hours' time in service of the tail rotor blade bonded assembly, P/N 76101-05020 or P/N 76088-20077. (c) For purposes of complying with this AD, the hours' time in service for the individual tail rotor horn and blade components that were not installed at the time of issuance of the initial rotorcraft airworthiness certificate must be determined from rotorcraft records. (d) Upon request, an alternate means of compliance which provides a level of safety equivalent to the requirements of this AD may be used when approved by the Manager, Boston Aircraft Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone (617) 273-7118. (e) Upon submission of substantiating data by an owner or operator through an FAA Aviation Safety Inspector, the Manager, Boston Aircraft Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone (617) 273-7118, may adjust the compliance time specified in this AD. This amendment (39-6171, AD 89-07-12) becomes effective on April 27, 1989. FOOTER:
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