AD 73-15-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Lycoming Engines | HIO-360-D1A | AVCO LYCOMING Model HIO-360-D1A Engines |
Unsafe Condition
Failure of Bendix part numbers 10-349235-3 and 10-349235-4 magnetos due to degraded rubber drive plate grommet (part number 10-391315).
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Required Actions
Replace the part number 10-391315 rubber drive plate grommet in accordance with Lycoming Service Bulletin No. 364 or equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.
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Compliance Time
within 300 hours time in service after the effective date of this AD and every 300 hours in service thereafter
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Affected Aircraft
AVCO Lycoming Model HIO-360-D1A engines installed on Hughes Models 269C and 300C helicopters.
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Federal Register Abstract
Rubber Drive Plate Grommet
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_73-15-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-15-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model HIO-360-D1A Engines Subject: Rubber Drive Plate Grommet Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/23/1973 Make: Lycoming Engines Model: HIO-360-D1A Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 73-15-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1689 AD NUMBER: 73-15-04 SUBJECT HEADING: AVCO LYCOMING Model HIO-360-D1A Engines ACTION: SUMMARY: DATES: Effective July 23, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-15-04 AVCO LYCOMING: Amdt. 39-1689. Applies to HIO-360-D1A model engines installed on Hughes Models 269C and 300C helicopters. Compliance required within 300 hours time in service after the effective date of this AD and every 300 hours in service thereafter. To prevent possible failures of the Bendix part numbers 10-349235-3 and 10-349235-4 magnetos, replace the part number 10-391315 rubber drive plate grommet in accordance with Lycoming Service Bulletin No. 364 or equivalent procedure approved by Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. This amendment is effective July 23, 1973. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_73-15-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-15-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model HIO-360-D1A Engines Subject: Rubber Drive Plate Grommet Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/23/1973 Make: Lycoming Engines Model: HIO-360-D1A 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: 73-15-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1689 AD NUMBER: 73-15-04 SUBJECT HEADING: AVCO LYCOMING Model HIO-360-D1A Engines ACTION: SUMMARY: DATES: Effective July 23, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-15-04 AVCO LYCOMING: Amdt. 39-1689. Applies to HIO-360-D1A model engines installed on Hughes Models 269C and 300C helicopters. Compliance required within 300 hours time in service after the effective date of this AD and every 300 hours in service thereafter. To prevent possible failures of the Bendix part numbers 10-349235-3 and 10-349235-4 magnetos, replace the part number 10-391315 rubber drive plate grommet in accordance with Lycoming Service Bulletin No. 364 or equivalent procedure approved by Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. This amendment is effective July 23, 1973. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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