Transcript for Cause of first lady's plane scare confirmed

Now to the investigation that is under way into that midair scare for the first lady. Smoke and a burning smell forcing the pilots to turn around minutes after takeoff and David Kerley is at Reagan national airport with the details. Good morning to you. Reporter: Good morning. The first lady, staff and some reporters had just taken off when secret service agents started moving to the front of the aircraft and reporters were told to put wet towels over their nose and mouths if the smoke got too bad. This morning we now know what caused the first lady's jet to quickly return to Andrews air force base. We're having some issues up here. Like to turn around and go back to Andrews. Reporter: The issue was smoke in the cabin. A smell of something burning. If you listen closely you can hear that the pilots of Mrs. Trump's jet have their oxygen masks on. Require any special assistance? No assistance required at this time, thanks. Reporter: Turns out on the converted 757 jet called bright star some communications equipment was overheating causing that smoke. The crew shut off the gear and the smoke cleared and took off their masks. We've got the situation all cleared up now but we still want to go back to Andrews. Reporter: They have a fleet of four to flow government officials. The average age, 18 years. Once this was on the ground the first lady called the president before she boarded another smaller jet. I said I hope this plane is better than the first one but they had a problem, yeah, they had a problem but she's fine. Reporter: And on the ground in Philadelphia, Melania trump made only a passing reference to the smoky cabin. I'm sorry for a little delay. Reporter: Now these 757s fly government officials including the vice president and occasionally the president. When air force one is too big for an airport that he's visiting. Thank you, robin.

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