AD 72-21-04

final rule
Data completeness: 70%

AVCO LYCOMING Model HIO-360-D1A Engines

AD Number
72-21-04
Status
final_rule
Effective Date
Product Category
engine
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
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

AI-generated summary from the source AD text. Verify against the official source before acting.

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.

AI-generated summary from the source AD text. Verify against the official source before acting.

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).

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

AVCO Lycoming Model HIO-360-D1A engines installed on Hughes Model 269C and 300C helicopters.

AI-generated summary from the source AD text. Verify against the official source before acting.

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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