Southwest Airlines Emergency Landing

David Maialetti /The Philadelphia Inquirer via AP

NTSB: Blown Southwest Jet Engine Showed 'Metal Fatigue'

April 18, 2018 - 12:51 pm
Categories: 

PHILADELPHIA (WCBS 880/AP) -- A preliminary examination of the blown jet engine of the Southwest Airlines plane 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.

Passengers scrambled to save Jennifer Riordan -- a Wells Fargo bank executive and mother of two from Albuquerque, New Mexico -- from getting sucked out the window that had been smashed by debris. She later died, and seven others suffered minor injuries.

This was Southwest's only passenger fatality since the airline was founded in 1967, CBS News' Kris Van Cleave reported.

The pilots of the twin-engine Boeing 737 bound from New York to Dallas with 149 people aboard took it into a rapid descent Tuesday and made an emergency landing in Philadelphia. Oxygen masks dropped from the ceiling and passengers said their prayers and braced for impact.

"I just remember holding my husband's hand, and we just prayed and prayed and prayed," said passenger Amanda Bourman, of New York.

The National Transportation Safety Board sent a team of investigators to Philadelphia.

In a late night news conference, NTSB chairman Robert Sumwalt said one of the engine's fan blades was separated and missing. The blade was separated at the point where it would come into the hub and there was evidence of metal fatigue, Sumwalt said.

“Metal fatigue means it’s old,” CBS News Transportation and Safety Analyst and former NTSB Chairman Mark Rosenker told WCBS 880’s Michael Wallace Wednesday, “and assuming a basic evidence of the fatigue, which enables it to crack off under even a light load.”

The engine will be examined further to understand what caused the failure. The investigation is expected to take 12 to 15 months.

Photos of the plane on the tarmac showed a missing window and a chunk gone from the left engine, including part of its cover. A piece of the engine covering, or cowling, was later found in Bernville, Pennsylvania, about 70 miles west of Philadelphia, Sumwalt said.

On Wednesday afternoon, Sumwalt followed up to note that air traffic controllers were able to see pieces of engine cowling also fell through the atmosphere elsewhere.

“The smaller parts will probably never be recovered. Certainly, that piece of the cowling was large enough that it was recognized, and then of course when it was picked up, the individual called the authorities and then it got back to the NTSB,” Rosenker said. “The smaller pieces of metal were probably scattered over a couple hundred miles. Most of those will never be recovered. But they have enough of what they have in the engine to do a very good forensic examination of what happened to that engine.”

Sumwalt said a preliminary rundown of flight data recorder information indicated that the cabin altitude warning was horn on the plane was activated after the damage to the engine occurred and the plane cabin began depressurizing rapidly. But despite losing altitude, the pilots were able to level the wings.

The flight crew elected to land with a lower setting on its flaps, which are used to increase the lift on the plane wings. Thus, the plane was moving far faster upon landing than normal, Sumwalt said.

Investigators have also removed the side wall area of the plane and have gotten a good look at the dents to the fuselage, Sumwalt said.

He said the NTSB crew also conducted interviews with flight attendants from the flight. Meanwhile, the engine and fan blade components that fell apart are being sent back to Washington, D.C. for what Sumwalt called “a very detailed metallurgical examination.”

As a precaution, Southwest said Tuesday night that it would inspect similar engines in its fleet over the next 30 days.

Passengers praised one of the pilots, Tammie Jo Shults, for her cool-headed handling of the emergency. The former Navy pilot was at the controls when the plane made the emergency landing. She walked through the aisle and talked with passengers to make sure they were OK after the aircraft touched down.

"She has nerves of steel. That lady, I applaud her," said Alfred Tumlinson, of Corpus Christi, Texas. "I'm going to send her a Christmas card, I'm going to tell you that, with a gift certificate for getting me on the ground. She was awesome."

In a recording of conversations between the cockpit and air traffic controllers, Shults reported that there was a hole in the plane and "someone went out."

Tumlinson said a man in a cowboy hat rushed forward a few rows to grab the woman and pull her back in.

"She was out of the plane. He couldn't do it by himself, so another gentleman came over and helped to get her back in the plane, and they got her," he said.

Passengers struggled to somehow plug the hole while giving the badly injured woman CPR.

As the plane came in for a landing, everyone started yelling to brace for impact, then clapped after the aircraft touched down safely, Bourman said.

Sumwalt said the woman who was killed in the accident was seated in Row 14. He noted that how the window in her row came out remains under investigation, as none of the acrylic from which the window is made was found inside the plane.

Investigators have also removed the side wall area of the plane and have gotten a good look at the dents to the fuselage, Sumwalt said.

He said the NTSB crew also conducted interviews with flight attendants from the flight. Meanwhile, the engine and fan blade components that fell apart are being sent back to Washington, D.C. for what Sumwalt called “a very detailed metallurgical examination.”

Southwest chief executive officer Gary Kelly said there were no problems with the plane or its engine when it was inspected on Sunday.

The jet's CFM56-7B engines were made by CFM International, jointly owned by General Electric and Safran Aircraft Engines of France. CFM said in a statement that the CFM56-7B has had "an outstanding safety and reliability record" since its debut in 1997.

Last year, the engine maker and the Federal Aviation Administration instructed airlines to make ultrasonic inspections of the fan blades of engines like those on the Southwest jet. The FAA said the move was prompted by a report of a fan blade failing and hurling debris. A Southwest spokeswoman said the engine that failed Tuesday was not covered by that directive, but the airline announced it would speed up ultrasonic inspections of fan blades of its CFM56-series engines anyway.

"There's a ring around the engine that is meant to contain the engine pieces when this happens," said John Goglia, a former NTSB member. "In this case it didn't. That's going to be a big focal point for the NTSB — why didn't (the ring) do its job?"

In 2016, a Southwest Boeing 737-700 blew an engine as it flew from New Orleans to Orlando, Florida, and shrapnel tore a 5-by-16-inch hole just above the wing. The plane landed safely. The NTSB said a fan blade had broken off, apparently because of metal fatigue.

(Copyright 2018 WCBS 880. The Associated Press contributed to this report.)