Driving into work the night of April 27, Air Traffic Control Specialist Richard Harrison knew that it would be a difficult shift. Listening to the radio on his way to the Atlanta Air Route Traffic Control Center in Hampton, Ga., Harrison heard reports of tornado warnings in the area. It was 10 p.m. and he had already seen television coverage earlier in the day of the tornado destruction in Birmingham, Ala.
The bad weather had already forced flights to be diverted all over the South. "We knew it was going to be one of those nights," Harrison said.
What he didn't know was that the tornadoes were headed directly his way and that he would soon be facing "the craziest night I've ever worked."
When Harrison, a 21-year veteran of air traffic control, arrived at work, things were already busy. "As soon as we get there we find out the tornadoes might be hitting the county where our families are," he said. He quickly called his wife and told her to stay in the basement.
The worsening weather meant that just a quarter of the airspace under the center's control was open for air travel -- the area that Harrison was assigned to cover. On a normal night there might be five or six planes holding in his airspace, tonight there were over 20. Four times the normal work load.
Harrison and a colleague worked to keep the planes outside the band of bad weather.
"It cuts down the amount of airspace that as a controller you can use to direct your flights," said Doug Church of the National Air Traffic Controller Association. "Their options were really limited."
Periodically, Harrison and the other controllers received updates from their supervisor. The alerts were escalating. Initially he recalled learning that "the tornadoes are kind of bad," but by 12:30 a.m., "We get to the last stage: imminent tornado," he said.
"The scary part comes when we get alerts from our supervisors that the tornadoes are heading towards us at work," he said. They had just five minutes to act.
As Harrison and his partner continued to try to clear the airspace, everyone deemed nonessential took shelter in the basement. "There is a handful of us left around, hoping that the roof won't be torn down."
"I guess we're essential!" Harrison joked.
Only a dozen people remained up in the control center. Normally, twice that many would have worked during the overnight shift.
"It was just really, really tense. And a lot of worry," Harrison said.
None of the stress was communicated to the pilots up in the air. In those five minutes Harrison had to inform another command center that they might have to take on some additional airspace and that the Atlanta center might go down if the tornado hit.
"Any kind of nervousness, it didn't come across to any of the pilots," he said. "We gave them a couple of heads up that they would have to go with a backup center." The pilots were informed that they might have to switch to listen to another command center on a different frequency.
But what if the control center was forced to shut down or, worse, if it were destroyed by the tornado?
"I can't even begin to imagine that type of scenario," Church said. "Other facilities would have to take over." The airspace controlled by the Atlanta center would likely come under the jurisdiction of centers in Washington, D.C., Indianapolis, Memphis, or Jacksonville. "They would take the bulk of the responsibility," Church said.