Airlines began inspecting some Boeing 737 engines on Wednesday as an investigation gathered pace into an explosion which killed a passenger on a Southwest Airlines flight in the first fatal U.S. airline accident in almost a decade.
This month European regulators ordered checks following lengthy analysis of a non-fatal incident at Southwest two years ago but investigators warn it is too early to say whether the two problems are linked.
Southwest Flight 1380 made an emergency landing in Philadelphia on Tuesday after an engine ripped apart mid-air, shattering a window on the 737 and nearly sucking out a passenger. One of 144 passengers died.
French accident investigators said they would send a team on Wednesday to assist the investigation led by the Washington-based National Transportation Safety Board because the engine was developed by a French-U.S. joint venture, CFM International.
France's Safran, which co-produces the engines along with General Electric, will also provide technical support, a spokesman for the Paris-based BEA air accident agency said.
Safran shares slipped in Paris, lagging a higher market.
All recent Boeing 737s are powered by engines from CFM, a workhorse of the global airlines that has logged more than 350 million hours of safe travel but some of which were also being examined after the 2016 accident.
CFM says there are more than 8,000 of its CFM56-7B engines in operation on Boeing 737 passenger jets.