AD 72-21-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Lycoming Engines | HIO-360-D1A | AVCO LYCOMING Model HIO-360-D1A Engines |
Unsafe Condition
Possible failures of the Bendix S4LN-1208 magnetos, P/N 10-349285-5
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Required Actions
Inspect and lubricate the magneto distributor bushing of both magnetos within the next 50 hours time in service and every 50 hours thereafter per Lycoming SB 336B or equivalent. Replace left magneto parts with Bendix Kit No. 10-391320 or equivalent FAA-approved parts within the next 100 hours time in service and every 100 hours thereafter.
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Compliance Time
Within the next 50 hours time in service and at each 50 hours time in service thereafter (for inspection/lubrication) and within the next 100 hours time in service and at each 100 hours time in service thereafter (for part replacement).
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Affected Aircraft
AVCO Lycoming Model HIO-360-D1A engines installed on Hughes Model 269C and 300C helicopters.
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Federal Register Abstract
Magnetos
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_72-21-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-21-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model HIO-360-D1A Engines Subject: Magnetos Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/13/1972 Make: Lycoming Engines Model: HIO-360-D1A Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 72-21-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1532 AD NUMBER: 72-21-04 SUBJECT HEADING: AVCO LYCOMING Model HIO-360-D1A Engines ACTION: SUMMARY: DATES: Effective October 13, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-21-04 AVCO LYCOMING: Amdt. 39-1532. Applies to HIO-360-D1A model engines installed on Hughes Model 269C and 300C helicopters. Compliance required as indicated after effective date of this AD. To prevent possible failures of the Bendix S4LN-1208 magnetos, P/N 10-349285-5, accomplish the following: 1. Within the next 50 hours time in service and at each 50 hours time in service thereafter, inspect and lubricate the magneto distributor bushing of both magnetos in accordance with Lycoming Service Bulletin No. 336B or later revision or equivalent procedure approved by Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. 2. Within the next 100 hours time in service and at each 100 hours time in service thereafter, replace those parts in the left magneto with the parts contained in Bendix Kit No. 10-391320 or equivalent FAA-approved parts. 3. Upon request, with substantiating data submitted through an FAA maintenance inspector, the compliance time may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. This amendment is effective October 13, 1972. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_72-21-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-21-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model HIO-360-D1A Engines Subject: Magnetos Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/13/1972 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: 72-21-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1532 AD NUMBER: 72-21-04 SUBJECT HEADING: AVCO LYCOMING Model HIO-360-D1A Engines ACTION: SUMMARY: DATES: Effective October 13, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-21-04 AVCO LYCOMING: Amdt. 39-1532. Applies to HIO-360-D1A model engines installed on Hughes Model 269C and 300C helicopters. Compliance required as indicated after effective date of this AD. To prevent possible failures of the Bendix S4LN-1208 magnetos, P/N 10-349285-5, accomplish the following: 1. Within the next 50 hours time in service and at each 50 hours time in service thereafter, inspect and lubricate the magneto distributor bushing of both magnetos in accordance with Lycoming Service Bulletin No. 336B or later revision or equivalent procedure approved by Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. 2. Within the next 100 hours time in service and at each 100 hours time in service thereafter, replace those parts in the left magneto with the parts contained in Bendix Kit No. 10-391320 or equivalent FAA-approved parts. 3. Upon request, with substantiating data submitted through an FAA maintenance inspector, the compliance time may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. This amendment is effective October 13, 1972. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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