Fan Blade That Broke on United Plane in Denver Had 3,000 Flights
(Bloomberg) -- The fan blade on a Pratt & Whitney jet engine had been used on about 3,000 flights since its last inspection when it failed on Saturday over suburban Denver. That was well within what the company and regulators previously believed was safe, according to two people familiar with the investigation.
The fan blade, apparently weakened from a growing fatigue crack, broke shortly after takeoff, raining debris onto the ground and causing minor damage to the United Airlines Holdings Inc. plane, a Boeing Co. 777-200. No one was hurt.
In 2019, the U.S. Federal Aviation Administration had required additional inspections of blades on PW4000 models with 112-inch fans following a 2018 failure on a United flight to Hawaii. The FAA order called for initial inspections starting after blades had completed between 6,500 and 7,000 flight cycles.
However, Saturday’s failure appears to have occurred well before then, said the two people, who requested anonymity because they weren’t permitted to discuss details of the inquiry.
The fan blade’s inspection history was reported earlier by Reuters.
The significance of the failure after only about 3,000 flights isn’t clear. It’s possible the inspection interval wasn’t adequate, but an investigation into the 2018 failure found that inspections had missed a growing crack. After that, the company had inspected more than 9,000 blades, according to the National Transportation Safety Board.
The FAA on Tuesday issued an emergency order requiring all fan blades on the Pratt & Whitney models used on the 777 be tested before planes could return to carrying passengers.
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