# 2026-17584: Lycoming Engines Face FAA Mandate for Piston Pins and Oil Inspections

2026-17584, Airworthiness Directives; Lycoming Engines, is a Federal Register rule from Transportation Department, Federal Aviation Administration published 2026-08-28, effective 2026-09-14; PRIA reads it as touching household money (as of 2026-09-04).

- Canonical: https://policyrisk.com/federal-register/2026-17584
- As of: 2026-09-04
- Plain-text twin of the page above; the HTML and this file carry the same facts.

## Facts
- Document number: 2026-17584
- Title: Airworthiness Directives; Lycoming Engines
- Type: Rule
- Agencies: Transportation Department; Federal Aviation Administration
- Citation: 91 FR 55451
- Published: 2026-08-28
- Effective: 2026-09-14
- Comments close: 2026-10-13
- Significant: no
- Touches household money: yes
- Regulation identifier numbers: 2120-AA64
- Last updated: 2026-09-04

## In one line

Lycoming Engines Face FAA Mandate for Piston Pins and Oil Inspections

## Summary

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.

## Effects PRIA read

- Immediate piston-pin replacement & inspections: cost, high. If your airplane has a Lycoming engine with piston pin P/N LW-13445 (with an FAA Form 8130-3 dated between January 7, 2021 and December 15, 2025, or with no readable/available Form 8130-3), you must replace the affected piston pin with a part eligible for installation. You must also do an oil chang…
- Ban on installing affected piston pins: cost, medium. After September 14, 2026, you may not install an affected piston pin as defined in the AD (P/N LW-13445 with an FAA Form 8130-3 dated January 7, 2021 to December 15, 2025, or with an unreadable/unavailable Form 8130-3) on any engine. A "part eligible for installation" must either not be P/N LW-1344…
- FAA estimated compliance cost per engine: cost, high. The FAA estimates this AD affects 957 U.S.-registered engines and estimates cost per engine at $2,370 (2 work-hours at $85 per hour = $170 labor plus $2,200 parts), for a U.S. total of $2,268,090. The FAA notes some costs may be covered under warranty.
- Limits on special flight permits: mixed, low. Special flight permits under 14 CFR 21.197 and 21.199 may be issued to allow flights for the piston-pin replacement provided no metal particulates are found during the required inspection. However, special flight permits are not allowed to perform the visual inspection of the oil filter, oil pressu…

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## Sources
- [2026-17584 on federalregister.gov](https://www.federalregister.gov/documents/2026/08/28/2026-17584/airworthiness-directives-lycoming-engines)
- [2026-17584 as published (PDF)](https://www.govinfo.gov/content/pkg/FR-2026-08-28/pdf/2026-17584.pdf)

## Related
- [Previous: 2026-17583, Airworthiness Directives; Various Helicopters](https://policyrisk.com/federal-register/2026-17583)
- [Next: 2026-17588, Safety Zones; Annual Events Requiring Safety Zones in the Captain of the Port L…](https://policyrisk.com/federal-register/2026-17588)
- [All Federal Register documents](https://policyrisk.com/federal-register)

Source: PRIA, https://policyrisk.com/federal-register/2026-17584 (as of 2026-09-04).