The FAA yesterday proposed an emergency airworthiness directive that will require operators of Lycoming engines to inspect and possibly replace off-spec connecting rod small-end bushings in Lycoming engines installed or overhauled between November 2015 and February 2017.
Publication of the emergency AD comes in the wake of Lycoming mandatory service bulletin SB 632 released last month that outlines the procedures for completing the engine inspections. The FAA says 778 airplanes on the U.S. registry will be impacted by the AD, which carries an estimated total cost to U.S. engine owners of $1.1 million, or about $1,425 per engine, if no replacements are required.
If connecting rod or bushing replacement is required, the expected costs range from $2,170 for four-cylinder Lycoming engines to $6,680 for six-cylinder engines. The FAA notes that some of these costs may be covered under warranty.
The FAA said five uncontained engine failures in Lycoming engines have been reported, creating an unsafe condition that warrants the quick adoption of the AD. The agency anticipates making the AD final within 30 days. Lycoming has adopted a 10-hour in-service time of compliance for the service bulletin inspections.
