A Southwest Airlines plane at Denver International Airport. (Photo courtesy of Denver International Airport)

The U.S. Department of Transportation says it will look into flight cancellations by Southwest Airlines that have left travelers stranded at airports across the country amid an intense winter storm that has killed dozens of people. Many airlines were forced to cancel flights due to the weather, but Southwest was by far the most affected. 

The Denver International Airport bore the brunt of the dysfunction, with 334 flights canceled and 275 delayed Tuesday after days of snarled air traffic, according to the tracking website FlightAware.  

Of the 2,890 flight cancellations in the U.S. early Tuesday, 2,522 were called off by Southwest, FlightAware shows. A Southwest spokesman says cancellations snowballed as the storm moved from the eastern to the western U.S., leaving flight crews and planes out of place.

Major U.S. airlines were broadsided by the massive weekend winter storm that swept across large swaths of the country but had largely recovered by Tuesday, except for one.

Problems at Southwest Airlines appeared to snowball after the worst of the storm passed. It cancelled more than 70% of its flights Monday, more than 60% on Tuesday, and warned that it would operate just over a third of its usual schedule in the days ahead to allow crews to get back to where they needed to be.


American, United, Delta and JetBlue, suffered cancellations rates of between none and 2% by Tuesday.

The disparity has triggered a closer look at Southwest operations by the U.S. Department of Transportation, which called the rate of cancellations “disproportionate and unacceptable,” and sought to ensure that the Dallas carrier was sticking by its obligations to stranded customers.

The size and severity of the storm created havoc for airlines. Airports were overwhelmed by intense snowfall and drifts. Airlines cancelled as many as 20% of their flights Saturday and Sunday and Buffalo Niagara International Airport, close to the epicenter of the storm, remains closed Tuesday.

Yet it has become clear that Southwest is suffering a disproportionate disruption. Of the approximately 2,950 flight cancellations in the U.S. by midday Tuesday, 2,549 were called off by Southwest.

Southwest spokesman Jay McVay said at a press conference in Houston that cancellations snowballed as storm systems moved across the country, leaving flight crews and planes out of place.

“So we’ve been chasing our tails, trying to catch up and get back to normal safely, which is our number one priority as quickly as we could,” he said. “And that’s exactly how we ended up where we are today.”

On Tuesday, Southwest apologized for “falling short” and letting down travelers and its own employees. 

The company said it had been fully staffed going into the busy holiday weekend. But the severe weather led the airline to issue a state of emergency Dec. 21 in Denver, and only Denver, even though bad weather was causing other airlines to cancel flights in other cities. 

The emergency order is considered routine and has been used by Southwest in the past. The company said it puts parameters in place, like requiring a doctor’s note when an employee returns to work if they called in sick. It allows the airline to require employees work overtime if asked and if the company has exhausted all other options. Workers who refuse could lose their jobs.

A labor shortage wasn’t the issue, said Chris Perry, a spokesperson for the airlines.

“We do not have a staffing issue across any portion of our operation,” Perry said in an email. “With this disruption, we’ve had a scheduling issue — a struggle to place flight crews and aircraft in the right places. That’s why we’ve drastically reduced our schedule to rebalance the airline.”

The operational emergency order stems from the company’s contract with Transport Workers of America Local 555, which represents its ramp workers. Southwest officials declined to say why DIA was the only airport impacted and they did not share how many workers were asked to work overtime or if any were terminated.

“We continue the work to recover our operation, we have made the decision to continue operating a reduced schedule by flying roughly one-third of our schedule for the next several days,” Perry said.

Employers are allowed to require overtime as part of the job, said Scott Moss, division director of the Division of Labor Standards and Statistics at the Colorado Department of Labor and Employment. But overtime must be paid and not conflict with the state’s Healthy Families and Workplaces Act nor the federal Family Medical Leave Act. Both provide limited time off, some with pay. The ability to take paid leave under the state’s Family and Medical Leave Insurance Program doesn’t start until Jan. 1, 2024. 

“Colorado is an ‘at-will employment’ state, meaning either party can terminate the employment relationship at any time,” Moss said in an email. But there are exceptions, he added. Contract agreements between the union and management or illegal terminations due to discrimination or retaliation wouldn’t apply.

Moss said he didn’t know if Southwest’s order violated state labor laws because he hasn’t viewed the contract, but added “Southwest Airlines has not been in touch with us about this.”

The Department of Transportation said on Twitter that it was “concerned by Southwest’s unacceptable rate of cancellations and delays & reports of lack of prompt customer service.” The tweet said the department would look into whether Southwest could have done anything about the cancellations and whether the airline was complying with its customer service plan.

Bryce Burger and his family were supposed to be on a cruise to Mexico departing from San Diego on Dec. 24, but their flight from Denver was cancelled without warning or notice, he said Tuesday. The flight was rebooked through Burbank, California, but that flight was canceled while they sat at the gate.

“Just like my kids’ Christmas sucks. It’s horrible,” Burger said by phone from Salt Lake, where the family decided to drive after giving up the cruise.

The family’s luggage is still at the Denver airport and Burger doesn’t know if he can get a refund for the cruise because the flight to California was booked separately.

Burger’s call logs show dozens of unsuccessful attempts to reach Southwest over two days. The company did responded to a tweet he sent. He said they offered him and his family each a $250 voucher.

Southwest did not comment immediately on Tuesday and information related to the cancellations was last updated on the company’s site Monday.

The president of the union representing Southwest pilots blamed the lack of crews to fly planes on scheduling software written in the 1990s and on management that he said failed to fix things after previous meltdowns, including a major disruption in October 2021.

“There is a lot of frustration because this is so preventable,” said the union official, Capt. Casey Murray. “The airline cannot connect crews to airplanes. I’m concerned about this weekend. I’m concerned about a month from now.”

Sun staff writer Tamara Chuang contributed to this story.

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