The Southwest Airlines Pilots Association (SWAPA) will tell a U.S. Senate panel Thursday the low-cost carrier's "overconfidence" in planning and a "systemic failure to provide modern tools" are responsible for a December meltdown.

SWAPA President Casey Murray will tell the Senate Commerce Committee that pilots "have been sounding the alarm about (Southwest's) inadequate crew scheduling technology and outdated operational processes for years. Unfortunately, those warnings were summarily ignored," he said.

The Senate hearing is reviewing causes of recent air travel disruptions, especially the Southwest holiday operational woes that resulted in more than 16,000 flight cancellations.

• Southwest CEO Jordan in the Eye of the Storm