PHILADELPHIA • An engine on a Dallas-bound Southwest Airlines flight with 149 people aboard apparently exploded on Tuesday, forcing an emergency landing in Philadelphia as one passenger was killed after she was nearly sucked out from a window of the plane, the airline and federal officials said.
The fatality on the flight from New York was the first in a US commercial aviation accident since 2009, according to National Transportation Safety Board (NTSB) statistics.
After an engine on the plane's left side blew, it threw off shrapnel, shattering a window and causing cabin depressurisation that nearly pulled out a female passenger, according to witness accounts and local news media reports.
"We have a part of the aircraft missing, so we're going to need to slow down a bit," the plane's captain Tammy Jo Shults told air traffic controllers in audio released on NBC News.
Asked by a controller if the jet was on fire, Ms Shults responded it was not but added: "They said there is a hole and someone went out."
NTSB chairman Robert Sumwalt told a news briefing in Washington that one person had been killed, but declined to elaborate. The 43-year-old was later identified as Ms Jennifer Riordan.
She was a vice-president of community relations for Wells Fargo & Company in Albuquerque, New Mexico, and leaves a husband and two children.
"The entire Southwest Airlines family is devastated and extends its deepest, heartfelt sympathy to the customers, employees, family members and loved ones affected by this tragic event," Southwest said in a statement.
The top half of her torso was out the window. There was a lot of blood because she was hit by some of the shrapnel coming off the engine after it exploded.
MR MAX KRAIDELMAN, 20, college student.
It's not a couple of minutes of freaking out and frantically saying goodbye; it's 25 minutes of sustained fear that this was the end. What do you say to your pregnant wife and your parents in your final moments? That's what I was trying to figure out.
MR MATT TRANCHIN, 34.
Flight 1380 had 144 passengers and five crew members, Mr Sumwalt said. The flight data recorder showed the plane was at about 9,900m when the engine failed about 20 minutes into the flight, according to CNN.
One passenger was taken to the hospital in critical condition, and seven other people were treated for minor injuries at the scene, said Philadelphia Fire Department spokesman Kathy Matheson.
Mr Sumwalt said the NTSB believes parts came off the engine but it has not determined if it was an "uncontained engine failure".
"There are protection rings around the engine to keep shrapnel from coming out. Even though we believe that there were parts coming out of this engine, it may not have been in that section of the engine that technically would qualify this as an uncontained engine failure," he said.
"We don't think there was a fire at all," he said.
He said the NTSB sees about three or four uncontained engine failures a year, including non-US carriers.
He added the investigation could take 12 to 15 months to complete.
Southwest said it was accelerating its existing engine inspection programme and conducting ultrasonic inspections of fan blades of the CFM56 engines on all of its 737 jets. The airline said it expects to complete the inspections within 30 days. Minimal flight disruptions may result, it said.
The death shattered an unprecedented string of more than nine years without an accident-related fatality on a US passenger airline.
The last fatal accident involving a US-registered carrier occurred near Buffalo, New York, on Feb 12, 2009, when a commuter carrier operated by Colgan Air crashed, killing 49 people on board and a man on the ground.
The NTSB shipped the Southwest plane's two black boxes, or crash-proof recorders, to its lab in Washington, where investigators did an initial download of the cockpit voice recorder on Tuesday night.
Television feeds and photos posted on Twitter show the front of the aircraft's left engine had been ripped open.
A metal piece that covers the exterior of the engine was found in Bernville, Pennsylvania, about 97km north of Philadelphia, Mr Sumwalt said.