David Paul Morris/Bloomberg/Getty Southwest Airlines
The Southwest Airlines Pilots Association (SWAPA) has blamed "management's poor planning" after more than 1,800 flights were cancelled over the weekend.
Following 808 cancellations on Saturday, the airline cancelled another 1,019 flights on Sunday, which accounts for 28% of their scheduled flights for the day, according to FlightAware.
Some of the cities with the most cancelled flights included SWA's hubs in Denver, Baltimore, Las Vegas, Chicago and Dallas, where the airline is based.
"We experienced weather challenges in our Florida airports at the beginning of the weekend, challenges that were compounded by unexpected air traffic control issues in the same region, triggering delays and prompting significant cancellations for us beginning Friday evening," Southwest tells PEOPLE in a statement. "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."
No other airlines appeared to be affected on the same scale, with American Airlines being the second-most impacted domestic airline on Sunday, cancelling only 143 (4%) of their scheduled flights.
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The Federal Aviation Administration (FAA) noted that they did experience an uptick in delays and cancellations due to bad weather and limited staffing, but that disruption was limited to Friday afternoon out of Florida.
ATC issues and disruptive weather have resulted in a high volume of cancellations throughout the weekend while we work to recover our operation. We appreciate your patience as we accommodate affected Customers, and Customer Service wait times are longer than usual. (1/2) pic.twitter.com/o1scQJ5lLb
— Southwest Airlines (@SouthwestAir) October 9, 2021
"No FAA air traffic staffing shortages have been reported since Friday. Flight delays & cancellations occurred for a few hours Friday PM due to widespread severe weather, military training, & limited staffing in one area of the Jacksonville en route center," the FAA tweeted in response. "Some airlines continue to experience scheduling challenges due to aircraft and crews being out of place."
SWAPA, which is currently in a legal battle with the airline, put the blame on Southwest, writing in a statement on Saturday that they are "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."
"Our Pilots will continue to overcome SWA management's poor planning, as well as any external operational challenges, and remain the most productive Pilots in the world. They will continue to be focused on their highest priority — safety. SWAPA Pilots are true professionals and will always maintain the highest level of responsibility to their crews, their passengers, and our airline," the statement concluded.
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The union filed a lawsuit against SWA in August, accusing the airline of breaking federal labor law by implementing new rules without negotiation during the COVID-19 pandemic, affecting pay rates and working conditions, according to the Associated Press.
Russell McCrady, vice president of labor relations at Southwest, said the changes were due to "unpredictable challenges" posed by the pandemic, and they did not require negotiation.
On Friday, SWAPA asked a court to temporarily block the airline from enforcing a federally mandated vaccination requirement, as they attempt to resolve their current lawsuit.