FAA Issues Special Airworthiness Information Bulletin Regarding Some Lycoming Engines

May 9, 2019 - The FAA has issued a Special Airworthiness Information Bulletin (SAIB) for Lycoming engines with parallel valve cylinders and head assemblies shipped between September 1, 2013, and April 30, 2015. This SAIB is in response to reports of cylinder cracking on some of these engines. Cracking could result in a range of events including loss of power or a rough running engine.

The FAA recommends checking the table included in the associated Mandatory Service Bulletin, published by Lycoming in October 2018, to see if your engine contains a cylinder that could be affected. Both the FAA and Lycoming recommend replacing, rather than repairing, all affected cylinders on engines included in this table at overhaul.

The FAA issues SAIBs as recommendations for airworthiness concerns where an airworthiness directive (AD) is not necessary. While these directions are not mandatory, they provide valuable guidance for aircraft owners and maintenance personnel to maintain their aircraft safely.