Delta Air Lines issued an apology to travelers for the continued problems following Friday's CrowdStrike system update, which caused thousands of flight cancellations throughout the country.

Passenger complaints about airlines rose sharply in the first half of the year, according to consumer watchdogs. The number of canceled flights declined, but delays and other problems increased.

A major winter storm continued to bring heavy snow, blizzard conditions and significant ice from California to the Northeast on Thursday.

The Department of Transportation says it is looking into the airline's flight scheduling practices and will hold it accountable for refunds. The 16,700 canceled flights cost Southwest $800 million.

The transportation secretary is one of the many travelers who had their flights cancelled in recent days. His happened the day after he met with airline CEOs about their operational struggles.

The transportation secretary is one of the many travelers who had their flights cancelled in recent days. His happened the day after he met with airline CEOs about their operational struggles.

The unofficial start of summer is offering a troubling look at what lies ahead for travelers during the peak vacation season. U.S. airlines canceled more than 2,800 flights over a five-day stretch including the Memorial Day weekend, as bad weather, crews calling in sick, and other factors snarled their operations.

The airline says it was forced to cancel more than 800 flights on Sunday alone due to poor weather and staff shortages.