U.S. National Transportation Safety Board (NTSB) Chairman Robert Sumwalt said Monday that damage to a fan blade in a Pratt & Whitney engine that failed in a United Airlines Boeing 777-200 is consistent with metal fatigue, according to a preliminary assessment. At a news briefing, Sumwalt said it was not clear whether Saturday’s failure of the PW4000 engine with a “loud bang” four minutes after takeoff is consistent with another engine failure on another Hawaii-bound United flight in February 2018 that was attributed to a fatigue fracture in a fan blade. The engine that failed on the 26-year-old Boeing Co 777 and shed ... (full story)