National Transportation Safety Board chairman Robert Sumwalt said one person was killed.
"We are very concerned", Mr Sumwalt said, referring to the overall challenge of detecting slow-developing metal fatigue.
"I just remember holding my husband's hand, and we just prayed and prayed and prayed", said passenger Amanda Bourman, of NY.
Family, friends and community leaders are mourning the death of Jennifer Riordan, of Albuquerque, N.M., a bank executive on a Southwest Airlines jet that blew an engine as she was flying home from a business trip to NY. They recovered the airplane's cockpit voice recorder and flight data recorder. They include investigating whether engineering problems caused the engine to blow out, whether the batch of metal used to build the engine was faulty or if a one-off event led to the engine's eventual failure.
Southwest Airlines clashed with CFM over the recommendation, stating to the FAA in October that airlines needed 18 months to do the works and that only certain fan blades should be inspected, not all 24 in engines. Sumwalt said the plane touched down at about 190 miles per hour, while a jet of that size would typically land at around 155 miles per hour.
European regulators last month ordered checks within just nine months of April 2, following the 2016 incident at Southwest. "At the hub. there's a fatigue fracture where this #13 fan blade would come into that hub". Part of a fan blade had separated from the engine, and inspectors found evidence of a crack in the fan blade, which they said was consistent with metal fatigue.
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The walkouts are occurring from state to state because of the Supreme Court decision in San Antonio Independent School District v. He said he could do so without raising taxes, because the state's economy is improving and existing state programs could be cut.
Manufacturers regularly inspect engines for hidden cracks using X-ray machines or ultrasound devices - the same kind of technology doctors use to check the health of expectant mothers. On Tuesday, the airline said it would accelerate inspections and complete them in the next 30 days.
"There are various iterations of that (engine) and so I can't say exactly what that airworthiness directive might have applied to at this point, but that will be part of our investigation", Sumwalt said.
Wednesday night, the FAA stated it would approve within the next two weeks a directive to inspect fan blades on all CFM56-7B engines with 15,000 cycles-in-service, about four years, without time spent in a maintenance shop.
Blades that fail inspection would need to be replaced. The airliner had 144 passengers and five crew members on board.
The pilots then might have concentrated on dealing with the depressurization that resulted from shrapnel from the engine, confirming that oxygen masks deployed, Sullenberger said.
Captain Tammie Jo Shults and First Officer Darren Ellisor issued a statement through the airline.
She also said that about two-thirds of safety briefings are given on video and some of those videos are produced by marketing teams rather than safety professionals, leading some travelers to think it's the start of an in-flight movie.
The plane landed at a higher speed than usual because the pilots were concerned they might not be able to control the plane, according to Sumwalt.