Transcript for Haze and burning smell forces first lady's plane to turn around

We turn now to the midair scare involving the first lady. Smoke filling the plane. The flight crew putting on oxygen masks. That plane forced to turn around. Here's ABC's David Kerley. Reporter: The first lady and reporters were forced to return to Andrews air force base after a haze and smell of something burning spread in the cabin. We're having some issues up here. Likely to turn around and go back to Andrews, you think you can coordinate that for us? Reporter: The pilots of the converted Boeing 757, dubbed "Bright star," donned their oxygen masks. Do you require any special assistance? No assistance required at this time, thanks. Reporter: But reporters on board were told to put wet towels over their noses if the smoke got too bad. The air force flies four of these 757s. Average age, 18 years. We've got the situation all cleared up now, but we still want to go back to Andrews. Reporter: The first lady boarded a smaller aircraft to make the trip to Philadelphia. I said, I hope this plane better than the first one. They had a problem. They had a problem, but she's fine. Reporter: And on the ground, Melania trump made only a passing reference to the smoky cabin. I'm sorry for a little delay. Reporter: The air force says it was some communications equipment that overheated, causing that smoke. That equipment was shut down and the smoke cleared, but the pilots wanted to come back here, David, as a precaution. Glad everyone is okay on that front. David, thank you.

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