Washington — The world’s busiest airport, in the US city of Atlanta, struggled to resume normal operations on Monday, sparking criticism after a power cut stranded thousands of passengers.
With electricity out for about 11 hours, some passengers could not disembark from their planes after landing.
Other passengers already in the terminal crowded the darkened concourses, where even some water fountains had reportedly stopped working.
"Still on plane for going on fifth hour," tweeted Anthony Foxx, the former transport secretary under president Barack Obama.
"Whatever the cause, it feels like this one was compounded by confusion and poor communication."
US carrier Delta, whose largest hub is in the southern city, said it had expected 300 more flight cancellations on Monday, mostly morning arrivals, "to give the operation there an opportunity to more quickly return to normal".
Delta said it had to scrap about 900 flights on Sunday, but expected its Atlanta schedule would return to normal by Monday afternoon.
Carrier Southwest said that it planned to operate a regular Atlanta schedule on Monday after it and all other carriers using the airport were hit by the power cut.
Flightview.com, which tracks air travel data, listed hundreds of flights as delayed, cancelled or diverted during the outage.
But on Monday, it showed an increasing number of scheduled departures as well as arrivals. "Power has been restored on all concourses," the Hartsfield-Jackson Atlanta International Airport announced on its Twitter account on Monday, about 11 hours after first reporting on the electrical disruption. Giving an idea of how many people were affected, the airport said that 5,000+ meals were being delivered to passengers. The Georgia Power company said that "power had been restored for all essential airport activities including all concourses and flight operations". The company said that the power outage was "very rare".
Although the exact cause was not yet known, Georgia Power said preliminary investigation suggested that a fire had damaged cables in the backup power system.
"No personnel or passengers were in danger at any time," the company said. Atlanta Mayor Kasim Reed apologised to the thousands of passengers whose day was disrupted, The Atlanta Journal Constitution reported on its website.
Several photos and videos taken from airport showed people walking or sitting in crowded airport corridors, with windows only partially cutting through the gloom.
Many aircraft were parked on the airport tarmac. A woman said she was waiting in the security line when "they turned off the lights. A few times they went off and then finally they shut off completely."
Passenger Mike Vizdos said that he and others were trapped on their aircraft because the power went out just as it reached the terminal gate after arriving from Costa Rica.
"Sat on the plane for six hours and then cleared customs and immigration," Vizdos said. He was still hoping to reach his home in Richmond, Virginia, the following day.
"There are thousands of stories," he said.
The airport announced earlier that it "sustained a power outage shortly after 1pm today [Sunday]". That led the Federal Aviation Administration (FAA) to place a "ground stop" on
flights inbound for Atlanta, meaning the aircraft were held at the airports from which they were to depart.
"The FAA Tower can operate normally. However, departures are delayed because airport equipment in the terminals is not working," it said.
Stranded people were not amused. "I haven’t eaten since 8AM central," one tweeted.
Others said they were waiting on the tarmac: "Atlanta airport doesn’t have power. I’m trapped on the runway."