FAA Issues New Airworthiness Directive for Certain Lycoming Engines.
The Federal Aviation Administration (FAA) has recently published an important Airworthiness Directive (AD) affecting specific Lycoming engine models. This AD, issued on October 31, 2024, addresses a critical safety concern related to connecting rod bearing failures.
Scope and Impact
The directive applies to approximately 26,500 Lycoming engines installed on various aircraft in the United States. These engines were manufactured between January 2009 and February 2017.
The Issue
The FAA has identified a problem with inadequate lubrication of connecting rod bearings in certain Lycoming engine models. This issue can potentially lead to engine failure or seizure, posing a significant safety risk.
Required Actions
The AD outlines specific steps that aircraft owners and operators must take:
- For engines with 200 or more hours since the last overhaul or repair, an oil change and filter inspection are required within the next 10 hours of operation.
- Repetitive oil changes and filter inspections are mandated every 50 hours thereafter.
- If metal is found in the oil filter, affected parts must be replaced before further flight.
Compliance and Costs
The FAA estimates the cost of compliance to be approximately $255 per engine. This includes the expenses for oil inspections, connecting rod bushing inspections, and potential replacements.
Background and Context
This AD is part of an ongoing effort by both Lycoming Engines and the FAA to address safety concerns stemming from non-conforming connecting rod bushings manufactured by a former Lycoming supplier. It builds upon previous service bulletins issued by Lycoming in 2017, including Service Bulletins 630 and 480F.
Next Steps for Operators
Aircraft operators should:
- Check if their engine is affected using Lycoming’s Engine Serial Number History Search.
- Review the full text of AD 2024-21-02 for detailed compliance instructions.
- Consult with their maintenance providers to ensure timely compliance with the directive.
For technical questions or clarifications, operators can contact Lycoming’s Technical Support team at 1-800-258-3279 or Technicalsupport@lycoming.com.
You can view and download the AD PDF here: AD 2024-21-02
This Airworthiness Directive underscores the importance of ongoing maintenance and safety oversight in aviation. By following these mandated procedures, operators can help ensure the continued airworthiness of their Lycoming-powered aircraft.
