LINTHICUM, Md. (WJZ) — FAA inspectors are trying to figure out exactly where and how a lightning bolt struck near BWI’s control tower, crippling traffic at one of the nation’s busiest airports for more than two hours.

Derek Valcourt has more on the investigation into what happened.

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Flights are back to normal, but the big question for FAA officials is how can they keep something like this from happening again?

With a single lightning strike, all air traffic at BWI came to a grinding halt, stranding thousands of passengers. Some of them were stuck all night long.

“It means I’m delayed for a second day,” a passenger said.

“I’ve already booked for tomorrow,” another traveler said.

“Mine got moved to a midnight departure and I was like, ‘Oh, great,'” a passenger said.

FAA officials report the lightning strike occurred at 2:21 p.m.– right in the middle of one of the busiest times of the day for airport traffic.

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One worker in the control tower got shocked when the electricity traveled through some equipment. So to prevent further injuries, officials shut down power to other systems inside the control tower. Without power, controllers couldn’t communicate with planes on the ground or in the sky.

“This is a pretty unusual circumstance. I’ve never heard of this happening before,” said Steve Hedges, Airplane Owners and Pilots Association.

Hedges says it was not just chaotic inside the control tower. In the air, pilots on approach to BWI had to act fast.

“When a tower goes dark, the plane’s suddenly up there calling and there’s no answer. Their approaches are turned off,” he explained. “You’ve got everything stopping in place. It’s just got to stop, and of course, airplanes just don’t stop.”

Those planes were then directed by controllers at other nearby facilities into a holding pattern. Some were diverted to other airports as workers scrambled to repair the lightning damage.

Then, at 4:38 p.m., the FAA announced operations at the control tower would resume, causing thousands of delayed passengers stuck at BWI to break into applause.

The air traffic controller that was injured experienced numbness in his arms and legs. He has already been treated and released from the hospital.

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Officials with the air traffic controllers union say they cannot remember another time that lightning has struck the tower.