One person was killed.
Now, the question becomes: How did this happen?
Aviation attorney Arthur Wolk spoke to Action News on Tuesday, and he said it appears to be a case of "uncontained engine failure." The big front compressor fans inside the engine appear to have flown apart during the flight.
"That resulted in pieces of it going through the engine containment vessel, called a nacelle, and a piece of it went and took out one of the windows and other pieces hit the fuselage," he said.
As for reports from passengers hearing an explosion, Wolk thinks that was the explosive decompression of the pressurized plane through the broken window that reportedly injured a passenger who was pulled into that small opening.
"All the air in this cabin, as long as it is, wants to go through that little hole at one time. That's what it is that sucks the passenger into the hole, to try to plug the hole. So that passenger takes the place of the window, unless the passenger get sucked completely out," he said.
That did not happen in this case.
Uncontained engine failures are rare but they do happen. In 2016 another Southwest 737-700 had a very similar incident, forcing an emergency landing in Pensacola, Florida.
It's still an open question as to what caused the failure. An NTSB team was dispatched to Philadelphia to start the investigation, and hopefully find some answers.
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