NPRM FAA-2025-1365

Became AD 2026-04-11

Proposed airworthiness directive · Lycoming Engines

Published
August 7, 2025 · 90 FR 38081
Comments due
September 22, 2025
Action
Notice of proposed rulemaking (NPRM)
Docket
FAA-2025-1365
Project
AD-2024-00684-E
FR document
2025-15039
Products
Engine

A proposal is not in force. If adopted, it becomes an AD, usually with changes. Only the Federal Register edition is official.

Summary

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.

The resulting AD

Notices in this docket · 1