A major airline suddenly can't seem to get passengers to their destinations on time, posting worst-in-the-industry on-time rates.
But, surprise. It's not an airline that cynics love to hate, mega-carriers United Airlines or American Airlines. And it's not an ultra-discounter like Spirit Airlines.
It's perennial consumer favorite Southwest Airlines. It typically sits atop customer satisfaction ratings, with such consumer-friendly policies as free checked bags and no fees to change a flight.
But recently, Dallas-based Southwest has had the worst on-time rates in America -- a shocking turn for an airline that once topped the industry in punctuality year after year and regularly bragged about it.
For the second consecutive month, Southwest has placed at the bottom of the monthly on-time statistics, according to data reported to the Department of Transportation. It is the first time since at least 1995, when the current DOT reporting system began, that Southwest ranked last for any month.
Seth Kaplan, managing partner at Airline Weekly, said it was surprising to see Southwest at the bottom of the heap of any consumer ranking.
"It's unusual," he said. "Although they have transitioned in recent years to more of a revenue-focused airline, they've always been an airline that got the operation right."
The reasons for Southwest's on-time woes are many. For one, Southwest has a penchant for scheduling flights close together, giving little wiggle room when flights encounter weather problems, for example, said Henry Harteveldt, a travel industry analyst at Hudson Crossing.
"Southwest schedules its planes so tightly, to maximize efficiency and keep fares low, that even a slight delay early in the morning can snowball into a larger delay through the balance of the day," he said.
Meanwhile, airline competitors have slowly improved their on-time rates, raising the bar on performance.
To improve its on-time rates, Southwest changed its schedule last week, extending for some routes the total time it allots for such tasks as flying, taxiing, loading and unloading passengers, and preparing the aircraft for the next flight.
But delays on Southwest could continue in the near term.
"Adjustments take several months to implement, due to the complexity of our schedule," said Southwest spokesman Brian Parrish. "But we do expect to see improvement by early next year."