McDonnell Douglas DC-10
May 25, 1979 - American Airlines Flight 191 crashed during takeoff near O'Hare International Airport while bound for Los Angeles. All 271 people on board and 2 on the ground were killed; this remains the worst plane crash in America. Engine No. 1 separated from the plane while on takeoff roll. The cause of the crash was due to a maintenance error and a design flaw with the engine's pylon. All DC-10s worldwide were grounded until modifications were made.