“I don’t recall seeing an airline experience such a massive operational problem as we are currently seeing at Southwest,” he said.
Most airlines operate on a “hub/spoke” basis, with planes returning back to a hub airport after flying out to other cities, but Southwest planes tend to make multiple stops across the country, he said.
Hub/spoke airlines can shut down specific routes when bad weather hits, resuming operations when conditions improve, but Southwest can’t do that as easily without disrupting multiple flights, he said.
David Vernon, another airline analyst at the financial firm Sanford C. Bernstein, said the system enables higher use of planes during normal times but can cause cascading negative effects when things go wrong.
Making matters worse for customers: Southwest has a policy of not exchanging tickets with other airlines, so the airline could not rebook passengers on other flights, Mr. Harteveldt said. The debacle could force the airline to “buy back” frustrated customers with deeper discounts or conduct more promotions, he said.
No single region or airport bore the brunt of the cancellations. On Tuesday morning, more than 155 flights originating at Denver International Airport, or about 17 percent of its outgoing traffic, were canceled, and more than 115 flights, or about 38 percent, were canceled out of Chicago Midway International. More than 100 flights were also canceled at Harry Reid International in Las Vegas, and similar numbers were reported for Baltimore-Washington International, Dallas Love Field in Texas and Nashville International in Tennessee.
It’s been nearly a week since the winter storm began wreaking havoc for millions of people counting on airlines to get them from point A to B. The number of canceled flight began to rise last Thursday, when airlines called off more than 2,600 of them. The next day, nearly 6,000, or about a quarter of all U.S. flights, were canceled across the country. On Saturday, Christmas Eve, nearly 3,500 flights were canceled, and slightly fewer, at about 3,200, were cut from the schedules on Christmas Day.