The site of a 1956 airliner crash at the Grand Canyon that helped spur major changes to aviation safety is being dedicated as a National Historic Landmark.
Two commercial airplanes collided on June 30, 1956, as they were flying 21,000 feet over the canyon in uncontrolled airspace. All 128 people aboard the two flights died.
The crash helped push discussions in Congress on managing airspace and creating what's now the Federal Aviation Administration. Improvements included collision-avoidance systems and flight data recorders.
The public can't visit the place where wreckage of the planes was scattered near the confluence of the Colorado and Little Colorado rivers. A plaque designating its place in history will be unveiled Tuesday at the east end of the Grand Canyon overlooking the crash site.
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