The Federal Aviation Administration (FAA) issued an Emergency Airworthiness Directive (EAD) that requires operators to inspect fan blades on certain CFM56-7B engines within 20 days.

The directive is based on a CFM International Service Bulletin issued today and on information gathered from the investigation of Tuesday’s Southwest Airlines engine failure. The inspection requirement applies to CFM56-7B engines. Specifically, engines with more than 30,000 total cycles from new must complete inspections within 20 days. The EAD becomes effective upon publication. The engine manufacturer estimates today’s corrective action affects 352 engines in the U.S. and 681 engines worldwide.