He’s spending part of his final stretch in office addressing problems that have again made Atlanta the butt of jokes about its infrastructure problems. One of the loudest critics was former U.S. Transportation Secretary Anthony Foxx, who vented on Twitter about the “total and abject failure” at the airport.

“I have no idea what happened here today. We all understand that snafus happen and most of the folks down here are doing their jobs to the best of their ability,” said Foxx, who was traveling through Atlanta on Sunday. “But, whatever the cause, it feels like this one was compounded by confusion and poor communication.”

‘Real answers’

The city’s response to the outage was complicated by the difficulties of fighting a fire that erupted in the electrical facilities that snake along tunnels deep beneath the airport.

The mayor and Georgia Power said the blaze knocked out both the substations and the backup system that powers Hartsfield-Jackson International Airport. Although firefighters responded to the fire shortly after it sparked around 12:45 p.m., it took about two hours to investigate and extinguish the blaze and hours more to clear the tunnels of noxious fumes, Reed said, before utility officials could inspect and begin to repair the damage.

The lack of information during those first few hours led to confusion and chaotic scenes at the airport. Thousands of passengers waited in limbo, some stranded on airplanes on the tarmac and others swirling in terminals trying to get cellphone reception or find a place to rest in the darkening airport.

Soon, jokes started circulating online comparing a blacked-out Hartsfield-Jackson with "The Walking Dead," the post-apocalyptic zombie series filmed in Atlanta. And it sparked reminders of other recent infrastructure fails, including the I-85 bridge collapse in the spring that strangled traffic for weeks and the *government's struggle to respond to snowfall in 2014 that paralyzed metro Atlanta.

Tara Davis and her aunt Donna were among the infuriated passengers stranded at the airport. The Illinois women were headed to New Orleans for a cruise to Mexico, but the delays left them fuming, spending hours in one line after the other. No one seemed to know what was happening, Tara Davis said.

“If I can avoid it,” she said, “from now on, I am never coming back through Atlanta.”

The mayor said Monday that he would refuse to “play the blame game,” but he said Georgia Power’s likely decision to build concrete casing to protect the backup switches would prevent another blaze from knocking out power. And he said the airport’s communications should have been “more frequent” and more emergency lighting should have been available.

But he described what he said was a difficult struggle over how to address the public with detailed updates when little was known. The passengers clamoring for information, he said, would only be satisfied with news that the power was going to be restored.

“Whenever you have thousands of passengers stuck on planes, I really don’t believe that there’s any pleasant message other than: We have the power restored and this is when we’ll have the airport fully operational, so this is when we’ll move on.”

He added: “We didn’t want to come forward to you until we had real answers.”