Airworthiness Directives; Lycoming Engines

Built by the Tribune's code from the Federal Register. No AI wrote this page. Published in the Federal Register Aug. 28, 2026. Document 2026-17584. Updated Nov. 6, 2026.

What it does

The FAA is adopting a new airworthiness directive (AD) for certain Lycoming Engines (Lycoming) Model O-235, O-540, and IO-540 engines with a certain piston pin installed. This AD was prompted by several reports of piston pin failure that resulted in metal particulate contamination in the engine oil and engine failure. This AD requires replacement of the affected piston pin with a part eligible for installation and, for certain engines, oil change and visual inspection of the engine oil filter, oil pressure screen, and oil suction screen for metal particulates. This AD also prohibits the installation of an affected piston pin on any engine. The FAA is issuing this AD to address the unsafe condition on these products.

The Federal Aviation Administration's summary, as published in the Federal Register.

What changed in the regulation

1 part of Title 14 of the Code of Federal Regulations:

14 CFR 39

Wording on eCFR: the day before it took effect and from the day it took effect (first part listed).

Compared with

The Federal Aviation Administration has published 482 final rules in 2026 so far, compared with 518 in all of 2025.

Counted by the Tribune from Federal Register records since Jan. 1, 2025.

Before this

968 earlier Federal Register documents under regulation identifier 2120-AA64 since Jan. 1, 2025.

Aug. 28, 2026 Final rule. Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes
Aug. 28, 2026 Final rule; request for comments. Airworthiness Directives; Bell Textron Canada Limited Helicopters
Aug. 28, 2026 Notice of proposed rulemaking (NPRM). Airworthiness Directives; Embraer S.A. Airplanes
Aug. 28, 2026 Final rule. Airworthiness Directives; Various Helicopters
Aug. 28, 2026 Final rule. Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG Engines
Aug. 28, 2026 Final rule. Airworthiness Directives; Leonardo S.p.A. Helicopters
Aug. 27, 2026 Final rule. Airworthiness Directives; The Boeing Company Airplanes
Aug. 27, 2026 Final rule. Airworthiness Directives; Airbus SAS Airplanes

Since then:

What happens next and when

This AD is effective September 14, 2026.

The agency's dates, word for word.

Check it yourself

The record as published

Document number	2026-17584
Action	Final rule; request for comments.
Agencies	Transportation Department; Federal Aviation Administration
Published	Aug. 28, 2026
Effective date	Sept. 14, 2026
Comments close	Oct. 13, 2026
Regulation identifier (RIN)	2120-AA64
Docket	FAA-2026-8789

Source: the Federal Register (public domain). The document in the Federal Register