might have put a cigarette out in the trash. >> the captain sends his first officer to assess the situation. >> so i look back and you couldn't see the back of the airplane for the sort of light blue, hazy smoke. and claude came back and he said, i don't like what's going on back there. i think we better go down. >> the pilots put on their oxygen masks and prepare for an emergency landing into the closest airport, cincinnati. the crew moves passengers forward in the cabin to get away from the smoke, but there is little else they can do. >> dropping oxygen masks to the passengers in a situation like this would do absolutely no good. the masks are designed so that they will take ambient air in and supplement it with oxygen. so even if the oxygen mask had been deployed, when you took a breath in, you're going to get ambient air in. >> a flight attendant empties a fire extinguisher, trying to control the smoke, but they can't find the source of the fire.