Official: Plane in Chicago had rare, serious engine failure

Federal safety officials are investigating an incident where pilots were forced to abort a takeoff and evacuate passengers from a burning American Airlines flight on a runway at Chicago O'Hare International Airport.A federal official says the airliner experienced a rare and serious type of engine failure Friday. It's called an "uncontained engine failure" and it happens when engine parts break off and are spewed outside the engine.The official spoke to The Associated Press on condition of anonym