NTSB investigators found evidence of metal fatigue in the left engine of the Southwest Airlines Boeing 737-700 that made an emergency landing at Philadelphia International Airport on April 17 after the pilots initially reported an engine fire. A woman died after an apparent engine explosion blew out a window and caused the cabin to depressurize, nearly pulling her from the aircraft, according to media reports. The passenger fatality was the first on a U.S. airline since 2009. There were ...