This is an archived article that was published on in 2014, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Editor's note: On Monday, the National Park Service marked the 58th anniversary of the collision over the Grand Canyon with wreath laying ceremonies at the United Airlines Memorial in Grand Canyon Pioneer Cemetery and the TWA Memorial in the Flagstaff Citizens Cemetery. A new National Historic Landmark will be dedicated next week. A previous version of this story was published in 2006, on the 50th anniversary.

United Flight 718 and TWA Flight 2 were four miles above the floor of the Grand Canyon when they collided in midair on a sunny morning just before Independence Day in 1956.

Both were traveling between 300 and 350 mph. The United plane's propeller and left wing sliced through the TWA's fuselage and cut off its signature triple-fin tail.

The TWA Lockheed Super Constellation, with Capt. Jack S. Gandy in command, nosed over and plummeted as blankets, clothing, magazines and perhaps people shot out the back of the lopped cabin. Thirty seconds later, the 70 passengers and crew were strewn a few hundred feet above the Colorado River, carnage and metal melded into grotesque chaos.

The United Douglas DC-7 took maybe three times longer to hit. Despite losing an engine and the skin and aileron on its left wing, the airliner still had some lift. Capt. Robert F. Shirley fought to pull up and clear the canyon rim.

A minute to 90 seconds after the collision, the Salt Lake City control tower received a garbled radio transmission: "Salt Lake, ah, 718 . . . we are going in." In the background, someone yelled, "Up . . . up." The plane penetrated 20 feet into the sheer wall of a towering canyon butte, annihilating the aircraft and 58 passengers and crew members.

It was the worst U.S. aviation disaster up to that time: 10:31 a.m., June 30, 1956.

The magnitude of the grisly midair crash over one of the world's natural wonders helped spur the federal government to establish the Federal Aviation Administration air traffic control system that now safeguards the skies.

'Sights I never want to see again' • The two flights over the canyon were first-class only. Passengers included TWA and United employees, their families and company executives, the wife of a Detroit mining and real estate magnate, business executives and attorneys, military officers and 14 children, including an infant.

More than 300 children lost one or both parents in the crash.

Though a handful of people claimed to have witnessed the collision, the Civil Aeronautics Board investigative team found all of them unreliable. That meant no one saw the crash, which may have been clearly visible from the main tourist centers on the South Rim.

It wasn't until two brothers who operated a sightseeing flight service spotted smoke June 30 that authorities even knew where to look.

It was immediately clear there would be no survivors.

Military personnel, Swiss and American mountain climbers, river guides and citizen volunteers joined in the recovery effort. Military helicopter pilots made 76 trips to the crash sites over 10 days in heat so blistering and air thermals so unpredictable the pilots risked their own lives.

The operation traumatized them.

"They are sights I never want to see again," Air Force helicopter team member Donald Hunter of Greenfield, Ind., told reporters after seeing the TWA wreckage on Temple Butte. "The most of any person I saw was half a woman."

Volunteers helped carry dozens of rubber body bags filled with remains to the canyon rim. In those pre-DNA-testing days, only a few of the victims could be positively identified.

Sixty-six of the 70 TWA victims were buried in a mass grave in Flagstaff, Ariz., on July 9, 1956. Some families took coffins home to bury them nearby.

Remains of those on the United flight were buried at the Grand Canyon National Park's Shrine of the Ages next to park headquarters on the South Rim.

'How could this have happened?' • On July 2, 1956, reporters who had camped at Cape Solitude on the rim above the confluence of the Colorado and Little Colorado rivers were allowed to fly over the wreckage of commercial aviation's two largest aircraft, burned to ash.

"You wonder," wrote Salt Lake Tribune reporter Bob Alkire, "how two giant four-engine airliners with tremendous wing spans and carrying tons of metal and equipment could so obliterate themselves along with their human cargoes."

The question haunted everyone, said Frank Wetzel, an 80-year-old Seattle resident and former Associated Press reporter in Salt Lake City who hitched a ride with Alkire and Tribune photographers in a chartered plane to the disaster scene.

"How could this have happened?" Wetzel said in 2006, as the 50th anniversary of the crash approached. "We talked about the terrible coincidence of time and space."

Also near the anniversary, expert William Waldock ticked off the small events that caused the crash.

Waldock, a professor and associate director of the Center for Aerospace Safety Education at Embry-Riddle Aeronautical University in Prescott, Ariz., said both planes were slightly delayed out of Los Angeles due to fog.

One plane was faster than the other. The United flight's destination was Kansas City, Mo. The TWA plane was headed for Chicago, but the former plane was flying north of the latter. Both were off-course, pushed along by a tail wind, yet still behind schedule.

Both were on visual flight rules, then mandatory in open airspace away from airport control towers. They were ordered to maintain 3,000-foot vertical flight separation, but both were at 21,000 feet.

TWA's Capt. Gandy had asked for clearance to climb from his assigned 18,000 feet to 21,000 feet, but controllers denied the request, telling him the United flight was too close. The controllers didn't tell Capt. Shirley about the TWA flight because they weren't required to do so.

Gandy was allowed to fly 1,000 feet above the clouds. Both pilots, as allowed, were seeking the best position to fly through 25,000-foot-high cumulus clouds building to 30,000 feet.

They likely were sightseeing —their companies' suggested marketing practice — when the TWA "Super Connie" rose into the United DC-7's path.

The pilots probably couldn't see each other. The passengers could, though, because the two airliners were flying parallel for quite a while.

"Literally, passengers could look out and see the other plane," Waldock said. Those on the DC-7 "knew they were going down. The Connie, those people probably didn't have much idea what was happening."

Open airways • Commercial aviation had boomed at the end of World War II, when the nation had a surplus of aircraft and trained pilots. Before the war, there were fewer than 300 airliners in the United States; in the first few years following the war's end in 1945, there were 2,000.

But there wasn't a tight control system, only designated airways that pilots could choose to use or not once they left an airport's airspace. Pilots were allowed tremendous freedom and usually operated under visual flight rules — that is, they were supposed to keep their eyes peeled for each other.

There was no radar tracking. Commercial flights were monitored via radio transmissions, but military and private craft pretty much had the run of the skies.

The Civil Aeronautics Authority operated as a division of the Commerce Department, which, with President Dwight D. Eisenhower's support, consistently cut funding for the CAA. Eisenhower was busy promoting the establishment of the nation's interstate highway system.

Even after a 1954 collapse of the primitive control system that grounded 45,000 passengers in East Coast airports, the government continued to slash airline safety funding.

The Grand Canyon crash shook the administration's resolve, though officials continued to move slowly on airline safety until 1958, when two military-civilian aircraft midair collisions killed 58 more people and Pan Am introduced its first Boeing 707 jet service.

In memory • After the Grand Canyon crash investigation concluded, the National Park Service closed the sites for 20 years.

In 1976, the park told the airlines to clean up the considerable amount of wreckage still littering the buttes that tower over the two rivers' confluence, one of the most beautiful and popular spots in the gorge.

Word of the crash reached many people via best-selling author Tony Hillerman's 2004 novel, Skeleton Man, a fictitious take on the real event.

Parts of the United DC-7 remained embedded in Chuar Butte on the 50th anniversary, and during certain times of the day under certain sunlight conditions, they glittered in the crevasses where they landed.

On Tuesday, July 8, 2014, the National Park Service will dedicate a new National Historic Landmark — the 1956 Grand Canyon TWA-United Airlines Aviation Accident Site in Grand Canyon National Park.

The dedication will take place at the Desert View Amphitheater looking out toward the crash site. —

Dedicating a new landmark

On Tuesday, July 8, 2014, the National Park Service will dedicate a new National Historic Landmark — the 1956 Grand Canyon TWA-United Airlines Aviation Accident Site in Grand Canyon National Park.

The 10 a.m. event will take place at the Desert View Amphitheater looking out toward the crash site.

The ceremony will remember those who perished in the crash, recognize the significance of the accident, and acknowledge family members and friends of the crash victims, the service said in a statement.