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Southwest Airlines canceled hundreds of flights over the weekend, blaming the woes on air traffic control issues and weather.
The airline canceled more than 1,000 flights in total, or 29% of its schedule, as of 7 p.m. ET Sunday, according to flight tracker FlightAware. That was the highest rate by far of the major U.S. airlines. Next in line was Allegiant, which canceled 6% of its flights. American Airlines canceled 5% of its flights, while Spirit canceled 4% on Sunday, according to the flight tracker. On Saturday, Southwest Airlines canceled more than 800 flights.
Southwest Airlines said in an emailed statement that it had experienced weather challenges in its Florida airports at the beginning of the weekend, which were compounded by unexpected air traffic control issues in the same region. Those issues triggered delays and prompted significant cancellations for the airlines beginning Friday evening.
"We’ve continued diligent work throughout the weekend to reset our operation with a focus on getting aircraft and crews repositioned to take care of our customers," said Southwest Airlines. "With fewer frequencies between cities in our current schedule, recovering during operational challenges is more difficult and prolonged."
The company said that it’s allowing customers to explore self-service rebooking options on Southwest.com, where they can get updates on the status of their travel.
"We experienced significant impact in the Florida airports yesterday evening after an FAA-imposed air traffic management program was implemented due to weather and resulted in a large number of cancellations," Southwest also said in a statement Saturday to FOX Television Stations.
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The company also tweeted about the disruption Saturday afternoon.
"ATC issues and disruptive weather have resulted in a high volume of cancellations throughout the weekend while we work to recover our operation," the post read. "We appreciate your patience as we accommodate affected Customers, and Customer Service wait times are longer than usual..."
However, Henry H. Harteveldt, president and travel industry analyst at The Atmosphere Research Group, based in San Francisco, points to other causes for the cancellations.
First, he says Southwest has scheduled more flights than it can handle, a problem that started in June. He also noted that Southwest operates what’s known as a point-to-point route network, and when a delay occurs, it "cascades" along the remaining flight segments. That’s because, for example, a Southwest flight departing Fort Lauderdale, Florida, for the airline’s home base of Dallas may make multiple stops along the way.
But Harteveldt says the most troubling reason is the likelihood that some pilots who oppose Southwest’s decision to mandate COVID-19 vaccinations are participating in an illegal job action where they call in sick or are engaging in a "work slowdown."
In a statement Saturday, the airline’s pilot union, Southwest Airlines Pilots Association, said that’s not the case.
"SWAPA is aware of operational difficulties affecting Southwest Airlines today due to a number of issues, but we can say with confidence that our pilots are not participating in any official or unofficial job actions," it said.
According to FOX Business, a Federal Aviation Administration spokesperson said that the air-traffic control issues ended on Friday.
"No FAA air traffic staffing shortages have been reported since Friday," an FAA spokesperson told FOX Business in a statement on Sunday. "Flight delays and cancellations occurred for a few hours Friday afternoon due to widespread severe weather, military training and limited staffing in one area of the Jacksonville Air Route Traffic Control Center."
"Some airlines continue to experience scheduling challenges due to aircraft and crews being out of place. Please contact the airlines for details about current flight schedules," the spokesperson added.
Parts of Florida were expected to see strong to severe storms Saturday evening. Flooding was also possible in some areas.
Other southern states experienced severe weather this week.
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Dozens of people had to be rescued Wednesday night in central Alabama, where the National Weather Service said as much as 13 inches of rain fell, and a south Alabama town temporarily lost its main grocery store when a creek came through the doors of the Piggly Wiggly. Near the coast, heavy rains caused sewage to bubble out of underground pipes.
In south Alabama near the Florida line, water covered some streets in the flood-prone Escambia County towns of Brewton and East Brewton, inundating a shopping center and sending as much as 3 feet of water into the Piggly Wiggly. Two schools had to cancel classes, said Escambia Sheriff Heath Jackson.
In Georgia, the National Weather Service said as many as 6 inches of rain fell in a crescent-shaped area from Columbus to Macon and then northeast toward Athens, Gainesville and South Carolina.
The Associated Press contributed to this report. This story was reported from Los Angeles.