1 dead after Southwest airplane with 149 aboard makes emergency landing at Philadelphia International Airport

One passenger died and seven others were injured Tuesday morning when a Southwest Airlines plane flying from New York to Dallas apparently blew an engine in midair, breaking a window, sending smoke into the cabin, and forcing an emergency landing in Philadelphia.

An investigation into the cause will likely focus on a fan blade that broke off from one of the  Boeing 737's  two engines, said Robert Sumwalt, chairman of the National Transportation Safety Board, in a briefing here Tuesday night. The blade, one of 24 that bring air into the craft's turbo fan engine, broke near where it connected to the engine's hub, he said. There was evidence of metal fatigue near the break, Sumwalt said.

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Less than a year ago, both the Federal Aviation Administration and the engine's manufacturer drew attention to problems with metal fatigue on the fan blades in the CFM56 engine series, which this plane has, after a similar incident in 2016, also a Southwest plane. The FAA proposed a directive that planes with extensive miles on their engines should subject the fan blades on those engines to a specific test designed to detect flaws in metal. Whether this plane's engines should have been subjected to those tests, and whether Southwest was performing them, will be investigated, Sumwalt said.

"We want to see if this part might have been subject to that airworthiness directive," he said. Officials did not immediately know when the engines were last inspected, he added.

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Details of the engine failure Tuesday portray a routine morning flight gone awry. The plane took off from LaGuardia Airport bound for Love Field in Dallas at 10:43 a.m., Sumwalt said.

The flight was carrying five crew members and 144 passengers, some of whom described hearing a loud boom in mid-flight before a window blew out and the smoke-filled plane suddenly dropped. The failure happened at 32,500 feet, at about 11:15, Sumwalt said.

"Everybody knew something's going on, 'This is bad, like really bad,' " passenger Timothy Bourman, a 37-year-old pastor from New York City, said in a phone interview from the terminal as emergency personnel surrounded the plane after it landed. "A lot of people started panicking and yelling, just real scared."

Pieces of the engine fell to earth. Investigators found part of the metal cowl that surrounds the engine in Bernville, Berks County, about 70 miles north of the city, Sumwalt said.

The identities of the pilot and copilot were not released; however, according to media reports, the pilot was identified as Tammie Jo Shults, a former Navy fighter pilot.

Passengers described a fast, chaotic descent. Jim Demetros, of Stamford, Conn., said he heard a "loud boom" and a window about three rows behind him on the other side blew out.

"Hectic-ness ensued inside the cabin with oxygen masks coming down," he said after leaving Terminal A-East to meet his family about 2:50 p.m.

He had been headed to a conference in San Antonio, Texas, but decided instead to head home to be with his two children and wife Cindy.

He had texted her as the plane was descending: "There was an emergency, problems with the plane and I love you and the kids."

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The crew initially reported a fire and donned oxygen masks.

A fire warning was likely triggered by engine damage, not flames, Sumwalt said. Crew members informed air traffic control they were initiating an emergency descent, vectored to Philadelphia International Airport, and requested emergency vehicles to stand by, Sumwalt said. The plane came down fast, he said, much faster than in a normal landing.

Investigators listened Tuesday to the communication between the plane and air controllers, and said the crew handled the failure with aplomb.

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"We listened to air traffic control communications," Sumwalt, himself a former 737 pilot, said. "It certainly sounded to me like they did an excellent job."

Pilots managed to guide the plane to a safe landing by 11:23 a.m.

One passenger, identified as Jennifer Riordan of Albuquerque, N.M., was rushed to an area hospital, where she died Tuesday afternoon. She was a vice president of community relations with Wells Fargo and a married mother of two.

Officials did not explain how she died, and the NTSB reported the Philadelphia medical examiner would determine cause of death. Other passengers were treated for minor injuries.

The incident — the first airline accident to result in a fatality on an American carrier since 2009 — quickly made national headlines as news cameras aired live footage of the grounded plane, its mangled engine appearing to be burst open. Passengers shared images and videos on social media from inside the cabin, sparking widespread interest while official details were scarce.

The plane, a Boeing 737-7H4 that began flying in 2000, was certified through 2021, according to FAA records. A review of repair data on the plane showed no previous significant engine problems, but a similar Southwest jet endured a comparable engine failure two years ago.

In that August 2016 incident, a Boeing 737-700 lost an engine fan blade flying from New Orleans to Orlando. The failure blew debris from the engine forward, piercing the plane's fuselage. The plane's cabin depressurized, but the debris did not enter the passenger compartment and no one was injured, according to the NTSB's initial report on the incident. That incident is also still under investigation, but there was evidence of a fatigue crack at the root of the blade, the NTSB reported.

The 2016 incident prompted the FAA to propose its 2017 airworthiness directive to require ultrasonic inspection of fan blades on that series of engine, the CFM56. The engine's manufacturer also issued in 2017 a recommendation that airlines pay close attention to the fans on those engines. Both the company's recommendation and the FAA's proposed directive were intended for engines with 15,000 cycles-in-service since the last engine shop visit.

"Engine failures like this are unusual, and to have one take the life of a passenger, that's really rare," Sumwalt said.

Philadelphia Fire Commissioner Adam Thiel said that when the aircraft reached the ground, there was a fuel leak and a small fire in the engine. The incident was placed under control at 12:32 p.m.

In a video message posted Tuesday evening, Southwest Airlines CEO Gary Kelly said Riordan's family is the company's "immediate and primary concern." He also said Southwest — which has 706 planes and flies about 4,000 flights a day — is "in the earliest stages of gathering information."

Southwest planned to conduct enhanced inspection procedures throughout its fleet after Tuesday's event, Sumwalt said.

A review of FAA data on engine repairs on Southwest flights from 2010 to 2017 found 27 incidents, two of which related to problems with fan blades, but neither appears to have resulted in any injuries.

The investigation into Tuesday's event would likely take 12 to 15 months, Sumwalt said. He asked anyone with video or pictures taken from inside the plane to send them to witness@ntsb.gov.

Despite the engine failure Tuesday, Kathy Farnan, 77, of Santa Fe, N.M., a passenger, said, "it was a beautiful landing." She added crew members "were fast on their feet" and kept passengers calm as the plane descended.

Passenger Matt Tranchin, 34, of Dallas, told reporters that flight attendants and some passengers worked to cover the hole in the plane.

Once the aircraft dropped and the oxygen masks fell, Tranchin spent what felt like the next half-hour thinking he wasn't "going to make it" and texting his wife, who is pregnant with their first child.

"I spent a lot of my time trying to articulate what my final words would be," he said, "to our unborn child, to my wife, to my parents."

He told them goodbye, and that he loved them.

Staff writers Mari A. Schaefer, Michele Tranquilli, Jan Hefler, Michael Boren, Julie Shaw, and Joseph A. Gambardello contributed to this article.