The Great Skies Mystery: When Planes Collide with Birds in Mid-Air We weren’t able to create a summary for you. Refresh your page to try again. The 1956 Grand Canyon was a mid - air collision that happened on Saturday, 30 June 1956 at 10:32 am Mountain Standard Time. A United Airlines plane running as United Airlines Flight 718 hit another airplane owned by Trans World Airlines (TWA), operating as Trans World Airlines Flight 2. The 1956 Grand Canyon was a mid - air collision that happened on Saturday, 30 June 1956 at 10:32 am Mountain Standard Time. A United Airlines plane running as United Airlines Flight 718 hit another airplane owned by Trans World Airlines (TWA), operating as Trans World Airlines Flight 2. May 5, 2025 · New theories have refocused attention on the 1956 tragic midair collision over the Grand Canyon that forever changed commercial aviation. The night of June 30, 1956, is one that Arizona state historian Marshall Trimble will never forget. May 5, 2025 · New theories have refocused attention on the 1956 tragic midair collision over the Grand Canyon that forever changed commercial aviation. The night of June 30, 1956, is one that Arizona state historian Marshall Trimble will never forget. The 1956 Grand Canyon was a mid-air collision that happened on Saturday, 30 June 1956 at 10:32 am Mountain Standard Time. A United Airlines plane running as United Airlines Flight 718 hit another airplane owned by Trans World Airlines (TWA), operating as Trans World Airlines Flight 2. May 5, 2025 · New theories have refocused attention on the 1956 tragic midair collision over the Grand Canyon that forever changed commercial aviation. The night of June 30, 1956, is one that Arizona state historian Marshall Trimble will never forget. Apr 17, 2024 · A memorial site at a Flagstaff cemetery marks the graves of dozens of victims who died when two passenger planescollided in the skies over the Grand Canyon in 1956.