Dean Potter, one of America’s best known rock climbers and adventurers, has been killed while attempting a winged-suit flying stunt in Yosemite National Park in California.

The 43-year-old’s fellow base jumper, Graham Hunt, 29, also died after base jumping from Taft Point, a 914-metre-high cliff, Yosemite National Park spokesman Scott Gediman said.

The pair had attempted to fly at high speed through a narrow gap in the granite cliffs but missed, smashing into the rocks.

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The two men’s bodies were found by a helicopter search on Sunday after the pair were reported missing late Saturday by friends.

“It’s tremendously sad,” Mike Gauthier, an occasional climbing partner of Potter’s, told the New York Times.

“Dean was part of this community and had such an impact on climbing. He was a luminary and in the pantheon of climbing gods.”

The “base” in base jumping stands for buildings, antennas, spans and Earth that jumpers can parachute from.

Extreme adventurer Dean Potter walks the tightrope in his home, Yosemite National Park. Photo: Facebook: Dean Potter

It is illegal in US national parks, and Potter fought and defied such laws throughout his career.

On his official Facebook page from May 8, Potter posted an image of four base jumpers at Yosemite, labelling it one of his “all-time favourite pictures of civil disobedience”.

Tributes have poured in from all over the globe for Potter, who was a pioneer in his field.

Extreme sports enthusiasts from all over the world took to the adventurer’s Facebook page to pay tribute to the man admired for his fearlessness and incredible courage.

“Part of me says it’s kind of crazy to think you can fly your human body,” Potter said in a 2008 interview with The New York Times.

“Another part of me thinks all of us have had the dream that we can fly.

“Why not chase after it? Maybe it brings you to some other tangent. Chasing after the unattainable is the fun part.”