VIENNA: Norman Dyhrenfurth, a Swiss-American mountaineer and filmmaker who organized the successful American expedition in 1963 to Mount Everest that put six climbers on the summit and inspired generations of Americans, has died. He was 99.

Ditta Vogt, the sister of Dyhrenfuhth’s longtime partner, Maria Sernetz, said he died Sunday in a Salzburg, Austria, hospital of natural causes.

Dyhrenfurth assembled the historic team of 19 mountaineers and scientists for the 1963 Everest Expedition that practically launched the modern U.S. mountaineering and outdoor industry by putting the first Americans on top of the world’s highest peak. The U.S.-led mountaineering expedition he led included 900 porters carrying about 26 tons of food, clothing, equipment and scientific instruments.

But he also was an accomplished cameraman and director who was head of the UCLA Film School in the 1950s and worked on movies such as Five Days One Summer and The Eiger Sanction, plus TV shows such as Americans on Everest.

In the half-century since the famous American expedition, mountaineering has changed so much that it is sometimes difficult to appreciate just how adventurous it was for a team of Americans to set out in 1963 trying to climb Everest by two different routes at once.

At an American Alpine Club celebration of the climb in 2013 in San Francisco, Dyhrenfurth joined three other living members of the expedition — Jim Whittaker, Tom Hornbein and Dave Dingman — in recalling the wet leather boots, the heavy oxygen canisters and other challenges.

“Americans, when I first raised it, they said, ‘Well, Everest, it’s been done. Why do it again?’ ” Dyhrenfurth said.

But once the feat was accomplished, the reasons were obvious. Dyhrenfurth and his team of pioneering climbers — captured in a Life magazine cover story and honored by President John F. Kennedy at a White House Garden reception — came to represent the birth of mountaineering as a popular sport in the United States.

The expedition enabled Whittaker — a Seattle resident who went on to become chief executive of outdoors outfitter Recreational Equipment Inc. — to become the first American to summit Everest. He and Sherpa Nawang Gombu reached the top of the world on May 1, 1963, a decade after New Zealand’s Edmund Hillary and Sherpa Tenzing Norgay made the first ascent in 1953.