| Date: | June 30, 1956 |
| Location: | Grand Canyon, Arizona |
| Aircraft: | Douglas DC-7 / Lockheed S Constellation |
| Reg: | N6902C/N6324C |
| Airline: | United Air Lines |
| Flight No: | 718 / 1 |
| Fatalities: | 128 : 128 |
| The wreckage of a United Airlines DC-7 after it collided with a TWA Constellation over the Grand Canyon in Arizona. All 128 people on both planes were killed. |