Will Smith Bungee Jumps Off Helicopter Over Grand Canyon for 50th Birthday

Will Smith just one-upped everybody once again by doing just about the craziest thing you could do for the big 5-0 ... bungee jumping out of a helicopter over the Grand Canyon.

Will documented his big jump Tuesday for his 50th birthday, where he, his family, Alfonso Ribeiro and a lot of spectators gathered in Arizona to watch the Fresh Prince take a plunging dive of death. He did it as a challenge from Yes Theory ... and did it in blazing fashion.

He was flipped around a bit like a rag doll on the way down, and eventually snapped back up after a couple seconds of disappearing out of the camera's view.

Once back on the ground, Will called the experience "pure bliss" ... and encouraged others to commit to conquering their fears.