Data / Federal rules / 2025-15039
Airworthiness Directives; Lycoming Engines
The Federal Aviation Administration published this proposed rule in the Federal Register on August 7, 2025. Comments closed on September 22, 2025.
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What the agency says
The FAA proposes to supersede Airworthiness Directive (AD) 2024-21-02, which applies to Lycoming Engines (Lycoming) model engines that have certain connecting rod assemblies installed. AD 2024-21-02 requires repetitive oil inspections for bronze metal particulates and, if found, additional inspections of the connecting rod bushings for damage, proper fit, movement, and wear, and replacement if necessary. As terminating action to the connecting rod bushing inspections, AD 2024-21-02 also requires replacement of the connecting rod bushings with parts eligible for installation. Since the FAA issued AD 2024-21- 02, the ship date range for potentially affected parts that may be subject to connecting rod failure has been expanded, and additional parts that are eligible for installation have been identified. This proposed AD would require the actions in AD 2024-21-02 and would require expanding the applicability. The FAA is proposing this AD to address the unsafe condition on these products.
Key facts
- Document number
- 2025-15039
- Type
- Proposed rule
- Action
- Notice of proposed rulemaking (NPRM)
- Agency
- Transportation Department; Federal Aviation Administration
- Published
- August 7, 2025
- Comments due
- September 22, 2025
- Dates
- The FAA must receive comments on this proposed AD by September 22, 2025.
- Docket
- Docket No. FAA-2025-1365; Project Identifier AD-2024-00684-E
- Regulation ID (RIN)
- 2120-AA64
- Code of Federal Regulations
- 14 CFR 39
- Topics
- Air transportation; Aircraft; Aviation safety; Incorporation by reference; Safety
- Pages
- 4
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Everything from the Federal Aviation Administration · Rules on air transportation · Rules on aircraft · Rules on aviation safety · Published in August 2025
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