European regulators this month began requiring an inspection by early next year of the type of engine that blew apart on a fatal Southwest Airlines flight on Tuesday, and a source said U.S. regulators were near a similar rule.
The actions by regulators show that there has been some concern, albeit non-urgent, about the engine, a workhorse of the global civil aviation fleet that has logged more than 350 million hours of safe travel but was also being examined after a 2016 accident.