Flight 940 was operating its scheduled flight route Mexico City-Puerto Vallarta-Mazatlán-Los Angeles operated by Mexicana Airlines (Compañia Mexicana de Aviación). On March 31, 1986, the flight departed from Mexico City utilizing a Boeing 727-264 registered as XA-MEM. Fifteen minutes into the morning flight, the plane crashed into a mountain named El Carbón in the rugged Sierra Madre Oriental mountain range of central Mexico.[2]