HFD officials said they got a call at 11:49am Sunday for smoke at Terminal B. The responding unit smelled smoke and called in other units to investigate.
"The power just went out," passenger Sean Swain said. "Everything was going about its business, and the lights just went out. The alarms are going off like this, flashing."
In what seemed like a matter of seconds to passengers, smoke began filling the hallways of the terminal, causing a prompt evacuation in the dark.
Crews discovered the smoke was coming from a malfunctioning transformer vault in the basement of one of the pods of Terminal B. No fire was found.
"We had a transformer that quit on us and, as a result, we've had a very significant impact at the operations of Terminal B," IAH General Magaer Carl D. Newman said.
The Terminal B security check-in was shut down and passengers were evacuated to Terminal C.
Donald DuPont was on his way to South Carolina before getting caught in the middle of the confusion.
"I came to B, and then when I was in B, they told me to go to C, and when I was in C, they told me to... If you think about all the effort that requires, it's probably going to put me in a situation where I'm going to miss my flight," DuPont said.
A new transformer was in place by 7pm and United Airlines officials it should be running by 1am Monday. Airport officials said a normal morning flight schedule should be maintained as a result.
No injuries were reported.
Delays were the biggest complaints from passengers trying to get out of the airport. For those coming in, the problems were just as frustrating.
"I thought somebody pulled the fire alarm," passenger Trina Wright of Louisville said. "It is kind of an inconvenience."
As soon as they landed by plane, passengers had to take a bus to Terminal C to pick up their luggage. Luggage airport employees were having to transport as well.
A spokesperson from United sent us a statement that read, in part: "We have teams in Chicago and Houston working on re-accommodation of customers as necessary due to delays and missed connections. We advise customers to check flight status frequently at United.com or with the mobile app for the latest."
No additional details have been released. It's unclear what caused the transformer to malfunction.
Terminal B is home to United Airlines' regional jet fleet. Passengers with United Airlines who were scheduled to fly out of Terminal B Sunday night were asked to find their United Airlines' ticket representative in Terminal C at IAH.
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