Southwest Airlines tells us that an indicator light came on right after Flight 48 from Houston to Dallas took off. As a precaution, the captain decided to go back and have the door checked.
Jeff Weingart was killing time at the airport when he saw it all unfold.
"I couldn't believe my eyes," he said. "I couldn't believe a plane as sophisticated as they are would take off with the cargo door open."
Southwest says no one was hurt, and maintenance was called out to check the door.
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