In this April 17, 2018 photo provided by Marty Martinez, Martinez, left, appears with other passengers after a jet engine blew out on the Southwest Airlines Boeing 737 plane he was flying in from NY to Dallas.
Earlier on Wednesday, National Transportation Safety Board Chairman Robert Sumwalt told a news conference that the incident began when one of the engine's 24 fan blades snapped off from its hub.
Last year, the FAA estimated that some 220 of these engines would require testing, having carried out a certain number of flights. "It might be a maintenance issue", Sumwalt said.
The NTSB said on Twitter that it would send a team to investigate Tuesday's crash. "It was just all incredibly traumatic, and finally when we. came to a halt, of course, the entire crowd was (in) tears and people crying and we were just thankful to be alive". "We lost an engine mid-flight and they guided back to Philly".
Johnson posted a picture of the shredded engine and thanked crew members, calling them #angelsinthesky.
The NTSB is focusing on preventive measures, Sumwalt said.
The blade had broken twice, where the blade attached to a hub and nearly halfway through it, Sumwalt said.
Metal fatigue is a weakening of metal from repeated use and involves microscopic cracks.
A retired nurse was among those on Southwest Flight 1380 who tried in vain to help save a New Mexico woman on Tuesday.
After the April 17 engine failure, Southwest said it will accelerate ultrasonic inspections of CFM56 engine fan blades "out of an abundance of caution", a process it expected will take 30 days.
It is unknown whether the FAA's original directive would have forced Southwest to quickly inspect the engine that blew up.
Last year, the engine maker and the Federal Aviation Administration instructed airlines to make ultrasonic inspections of the fan blades of engines like those in Tuesday's accident.
The engine was a CFM56-7B, a development of the original CFM56 engine that was first produced in the 1970s.
Failure The intention is that any debris from such a failure should be contained within the engine and its cowlings, since released debris may have very high energy and present a serious threat to the aircraft's structure and systems.
The NSTB wants to locate every piece of the damaged engine and then rebuild it.
Residents have reported some debris but no "internal components" have been recovered yet. Passenger Kathy Farnan said, "They were also taking care of everybody with running around with oxygen, making sure everybody had enough oxygen".
"Jennifer's vibrancy, passion, and love infused our community and reached across our country", her family said.
While the airline decided not to identify the pilot, saying only that the employee has years experience on the job, passengers posting on social media identified her as Tammie Jo Shults.
Sumwalt said the pilots were able to straighten the jet within seconds after going into a 41.3 degree angle - something not common at all. He also noted "a fair amount of vibration" and said the airliner landed in Philadelphia at an above-average speed of 190 miles per hour. The usual speed is 135 knots.
"When the window ruptures, you have those two pressure levels trying to equalize", said Ladd Sanger, an aviation attorney and licensed airplane and helicopter pilot.