The Federal Aviation Administration (FAA) revealed it ordered a ground delay to slow traffic due to staffing issues in the airport's air traffic control tower.
As a result, some travelers faced an average delay of about 90 minutes.
The delays come after the FAA issued a ground stop at about 3:55 p.m., which has since been lifted. The ground delay was expected to remain in effect until 9:59 p.m.
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