PHOENIX - An engine failure on a Southwest Airlines plane turned an unremarkable trip to Dallas into a disaster on Tuesday.
A preliminary examination of the blown jet that set off a terrifying chain of events and left a businesswoman hanging half outside a shattered window showed evidence of "metal fatigue," according to the National Transportation Safety Board.
“We may be seeing a new phenomenon involving engines as they get old,” said Bill Waldock, an expert on aircraft accident investigations with the Embry Aeronautical University.
“They're going to figure this out pretty fast, because it affects so many aircraft and so many engines,” he said.
This was the second mid-air engine accident on a Southwest plane in the last two years. No one was seriously hurt in the August 2016 incident, when a Southwest flight made an emergency landing in Florida after a fan blade separated from the engine.
“Unfortunately, a lot of times we discover there's a problem when it fails,” Waldock said.
Last year, the Federal Aviation Administration called for ultrasonic inspections of the engine’s fan blades in response to the 2016 incident.
Those inspections had still not been approved when the Southwest jet engine explosion occurred this week.
Southwest is ordering inspections of its entire fleet.