The Latest: Investigators say crack in engine led to failure

PHILADELPHIA (AP) — A federal investigator says that a crack on the interior of a jet engine is what led to the failure that shot debris at the plane, leading to the death of a passenger. National Transportation Safety Board chairman Robert Sumwalt said at a news conference Wednesday that one of the 24 blades in the Southwest Airlines 737's engine fractured from metal fatigue. Sumwalt says he is very concerned about Tuesday's engine failure, but would not extrapolate that to the CFM56 engines or the entire fleet of Boeing 737s. The plane is the most popular airliner ever built. He says investigators are still trying to figure out how a window came out of the plane. Sumwalt says that the woman who was wearing a seatbelt and sitting next to the window died.