Fatal Southwest Accident

Federal investigators are probing the role a broken engine fan blade played in the catastrophic event aboard the Southwest Airlines flight that resulted in the first fatal accident onboard a U.S. aircraft in nine years.

What the investigators uncover could have wide-reaching implications for a popular CFM56-7B engine type that is used in thousands of aircraft across the world. Late Wednesday, U.S. regulators said they would issue an order within two weeks calling for inspections of fan blades on certain CFM56-7B engines.

National Transportation Safety Board Chairman Robert Sumwalt said the broken fan blade initiated a chain of events that led to the failure of the left engine and, ultimately, the death of a New Mexico woman onboard the flight, who suffered severe injuries when a window blew out and she was nearly sucked out of the plane as the cabin rapidly depressurized.

The New York to Dallas flight diverted to Philadelphia, with seven other passengers reporting minor injuries. The victim in Tuesday’s accident, Jennifer Riordan, died from “blunt impact trauma of the head, neck and torso,” according to the Philadelphia Medical Examiner’s office.

The blade showed signs of metal fatigue, Sumwalt said during a Wednesday press briefing, with microscopic cracking on the interior of the fan blade that would not have been visible to the naked eye.

“Engine failures like this should not occur,” he said. “If we feel this is a deeper issue, we have the capability to issue urgent safety regulations.”

Southwest said Tuesday evening that it would perform ultrasonic scans within the next 30 days on all its engines that have not recently undergone that inspection. Tuesday’s death was the first passenger fatality from an accident in the Dallas-based carrier’s 47-year history.

The company is cooperating with the NTSB and has sent a team to assist with the investigation in Philadelphia, but did not provide any public updates Wednesday.

Sumwalt emphasized that the investigation is still in its early stages and a final cause for the accident likely won’t be identified for a year or more.