Delta went down due to a 'power outage,' though it may not be what you think

On its website, Delta Air Lines touts that it was named one of Fortune's 50 most admired companies this year, in part because its "industry-leading global network" connects 180 million passengers per year to 335 destinations in 61 countries around the world.

But on Monday, a lot of those passengers were going nowhere, and admiration was probably not the first word that came to mind when they thought of Delta. The airline has canceled more than 650 flights as of 5 p.m. ET on Monday after what they described as a "power outage" -- something that may only be true in a nontraditional sense.

Aviation experts say the power outage may have been somewhat self-inflicted.

Georgia Power, which provides electricity to millions of people in Georgia, where Delta's headquarters are located, said its systems were running fine, and pointed its finger back at the airline.

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That information led Bob Mann -- who formerly worked for American Airlines and now runs an airline advisory business -- to believe Delta's outage may have been a test gone awry.

When an airline's computer systems find they cannot run on a regular flow of electricity, they switch to back-up generators almost instantly. Airlines often test their back-up systems during downtime in air traffic, and Delta's problems began at 2:38 a.m. ET.

These tests often run normally, and no one notices. This time, though, Mann said Delta may have experienced a problem with the switch that transfers the computer system's main power to its back-up source.

"The irony may be that although the system performed normally in every prior test, in this particular case the thing failed rather spectacularly, which didn't allow them to use Georgia Power and didn't allow them to use any local generator power," Mann told Mashable.

Without a main nor a back-up power source, Delta's check-in systems went haywire, its app was a mess, and boarding passes had to be handwritten, collectively stifling the airline.

Delta didn't specifically mention a test, like in Mann's scenario, but did say it canceled flights "due to a loss of power affecting Delta operations systemwide."

"Following the power loss, some critical systems and network equipment didn’t switch over to Delta’s backup systems," the company said in a statement. "Delta’s investigation into the causes is ongoing."

The problem called to mind the damage a potential cyberattack could do to an airline if hackers were able to take control of an airline's power sources, ciphering off the main power along with any back-up generators, effectively taking the flying experience back several decades.

Delta's issues seem be different from the outage-caused delays at Southwest last month and delays United Airlines has seen in the past, both of which stemmed from connectivity issues with a router. In Southwest's case, back-up systems didn't work according to plan. In Delta's case, back-up systems may never have gotten a chance to work in the first place.

Delta has done damage control through a series of online updates and a video of CEO Ed Bastian in which he assures customers that fixing this issue is "an all-hands on deck effort."

Though the airline has sputtered back to life since the initial chaos, it remains to be seen just how many days of delays and cancellations will result from the outage.