AD 78-07-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Honeywell International Inc. | T5508D | AVCO LYCOMING Model T5508D Engines. |
Unsafe Condition
Fatigue failure of the engine accessory inner bevel gear leading to engine stoppage.
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Required Actions
Remove inner bevel gear P/N 2-070-005-02 and replace with inner bevel gear assembly P/N 2-070-030-01, in accordance with Avco Lycoming Service Bulletin No. 5508-0013.
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Compliance Time
by May 1, 1978
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Affected Aircraft
Avco Lycoming T5508D model turboshaft engines.
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Federal Register Abstract
Inner Bevel Gear Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_78-07-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-07-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model T5508D Engines. Subject: Inner Bevel Gear Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/30/1978 Make: Honeywell International Inc. Model: T5508D Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 78-07-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3166 AD NUMBER: 78-07-04 SUBJECT HEADING: AVCO LYCOMING Model T5508D Engines. ACTION: SUMMARY: DATES: Effective March 30, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-07-04 AVCO LYCOMING: Amendment 39-3166. Applies to Avco Lycoming T5508D model turboshaft engines. Compliance is required by May 1, 1978. To prevent fatigue failure of the engine accessory inner bevel gear leading to engine stoppage, remove inner bevel gear P/N 2-070-005-02 and replace with inner bevel gear assembly P/N 2-070-030-01, in accordance with Avco Lycoming Service Bulletin No. 5508-0013, dated March 15, 1978, or later revision approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. The manufacturer's service bulletin identified and described in this directive is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Avco Lycoming Division, 550 South Main Street, Stratford, Connecticut 06497. These documents may also be examined at Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, and FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. This amendment becomes effective March 30, 1978. FOOTER:
Document Text
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AD Final Rules - DRS_78-07-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-07-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model T5508D Engines. Subject: Inner Bevel Gear Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/30/1978 Make: Honeywell International Inc. Model: T5508D Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 78-07-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3166 AD NUMBER: 78-07-04 SUBJECT HEADING: AVCO LYCOMING Model T5508D Engines. ACTION: SUMMARY: DATES: Effective March 30, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-07-04 AVCO LYCOMING: Amendment 39-3166. Applies to Avco Lycoming T5508D model turboshaft engines. Compliance is required by May 1, 1978. To prevent fatigue failure of the engine accessory inner bevel gear leading to engine stoppage, remove inner bevel gear P/N 2-070-005-02 and replace with inner bevel gear assembly P/N 2-070-030-01, in accordance with Avco Lycoming Service Bulletin No. 5508-0013, dated March 15, 1978, or later revision approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. The manufacturer's service bulletin identified and described in this directive is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Avco Lycoming Division, 550 South Main Street, Stratford, Connecticut 06497. These documents may also be examined at Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, and FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. This amendment becomes effective March 30, 1978. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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Related Airworthiness Directives
94-02-01
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