Grand Canyon Disaster (United Airlines 718 and Trans World Airlines 2) Mayday : Season 12 Episode 6

On 30 June 1956, United Airlines Flight 718 collides with Trans World Airlines Flight 2 over the Grand Canyon in Arizona. All 128 occupants on both flights are killed. At the time, it was the deadliest airline crash in history, and would lead to sweeping changes in the regulation of flight operations over the US.