The National Transportation Safety Board said they found possible cause of Boeing 777 engine's failure
The National Transportation Safety Board said they have found a possible cause of the American Airlines Boeing 777-200 engine’s explosion after a preliminary assessment.
According to the NTSB chairman Robert Sumwalt, after analyzing the flight data and cockpit voice recorders, the investigation group could assume that the cause of the damage to a fan blade in Pratt & Whitney PW4000 engine could be metal fatigue.
“What is important that we really truly understand the facts, circumstances and conditions around this particular event before we can compare it to any other event,” Sumwalt said at a news briefing.
On Tuesday, the United Airline’s fan blade is transported to a Pratt laboratory where it will be examined under the supervision of NTSB investigators.
“United Airlines has grounded all of the affected airplanes with these engines, and I understand the FAA is also working very quickly as well as Pratt & Whitney has reiterated or revised a service bulletin,” Sumwalt said. “It looks like action is being taken.”
Sumwalt added that the United Airlines incident must not be considered as an uncontained engine failure because the containment ring contained the parts as they were flying out. However, according to the chairman it still remains unclear why there was fire and a “loud bang” of the explosion since indications that fuel to the engine had been shut off.
The Federal Aviation Administration’s appropriate inspection protocol has not been released yet. Until then, the 777 Boeing plane are recommended to be suspended from the scheduled flights.