British Airways Plane on Fire in Flight scare in the air. This is what passengers on board a british airways flight saw out their window. Smoke pouring from the engine. Their quick-thinking pilots forced to make an emergency landing. Tonight, abc's nick schifrin, with the passengers who witnessed it all right through their windows. Reporter: Right after takeoff, a harrowing sight. Flight 762's engine was on fire. It had suffered a major technical fault or was struck by birds. Inside the cabin, john chaplain looked out his ow. The left engine flap had blown off. Loud boom and then there was orange colors filling the cabin. So that was quite scary. Reporter: The right engine, consumed by flame, now useless. Did your heart skip a few beats? It's -- you get a bit philosophical about it and wonder if this is your moment. Reporter: The pilot flew low, back toward the airport. When he landed safe -- but then john had to evacuate. He slid out an emergency exit, his hands trem pming so much, he could barely hold his camera steady. There were people throwing up as we got off the plane on the grass and crying and hysterics. Reporter: He can't forget the moment when he tried to call his wife. I was thinking back to the phone calls from 9/11 and how moving some of those messages were and I wondered if I would be the one leaving a message. Reporter: John told me he'll toast the pilot, because it could have been so much worse. Nick schifrin, abc news, at heathrow airport.