Japanese and American airlines ground dozens of Boeing 777 planes after dramatic engine failure that United Airlines Flight 328 experienced over Denver this weekend. According to National Transportation Safety Board investigation underway , two blades of the number 2 engine fan of the aircraft avaient developed fractures.
The Federal Aviation Administration has issued an Emergency Airworthiness Directive which requires "immediate or intensified inspections of Boeing 777 aircraft equipped with certain Pratt & Whitney PW4000 engines." The administration noted that this would likely result in the aircraft being taken out of service.
Boeing has also asked airlines to stop flying aircraft equipped with the engine, according to The Wall Street Journal .
"We have reviewed all available safety data following yesterday 's incident ", said Steve Dickson, FAA Administrator, in a statement. instruction . "Based on initial information, we concluded that the inspec intervaltion sh ould be stepped up for the hollow fan blades which are unique to this engine model, used only on Boeing 777 aircraft. "
United Airlines says that he voluntarily ground 24 Boeing 777s which use the Pratt & Whitney 4000 series engines and expects “only a small number of customers will be inconvenienced.” Japan's Civil Aviation Bureau has ordered Japan Airlines and All Nippon Airways to withdraw from the service their planes equipped with the same engines; JAL operates 14 and ANA has 19, according to Reuters .
No one was injured on United flight 328, which was bound for Honolulu but returned safely in Denver after experiencing an engine failure shortly after takeoff.
Update, February 22, 00:00 ET: Added mention of The Wall Street Journal report.