The failure was caused by a power outage in Atlanta at 2:30 a.m. ET.
The issue is not because the airlines are slow on upgrading their technical systems, Former Continental Airlines CEO Gordon Bethune said on CNBC's "Squawk on the Street."
"It's very complicated, like a wristwatch. You need one part to stop the whole thing," Bethune said.
The airlines are having to revert to a manual process where the automatic process has failed, he explained.
Most airlines have their own backup system with generators in case of a power failure, he noted.
"This power failure doesn't sound like the whole story because I'm sure Delta had generators and things to run their systems," he said.
Power failures cause a domino effect and create other problems, Bethune added.
Airlines take a big hit on the bottom line from being offline for even a few hours. The companies receive no money, must book new flights for passengers and pay for hotel rentals, he said.
Delta stock is higher this morning.
Separately, TheStreet Ratings team set this stock as a "buy" with a rating score of B. The company's strengths can be seen in multiple areas, such as its growth in earnings per share, increase in net income, good cash flow from operations, largely solid financial position with reasonable debt levels by most measures and notable return on equity. TheStreet Ratings team feels its strengths outweigh the fact that the company has had lackluster performance in the stock itself.
TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this articles's author. TheStreet Ratings has this to say about the recommendation:
You can view the full analysis from the report here: DAL