Jeb Corliss wants to fly  not the way the Wright brothers wanted to fly, but the way we do in our dreams. He wants to jump from a helicopter and land without using a parachute.

And his dream, strange as it sounds, is not unique. Around the globe, Mr. Corliss said, at least a half-dozen groups  in France, South Africa, New Zealand, Russia and the United States  have the same goal in mind. Although nobody is waving a flag, the quest has evoked the spirit of nations’ pursuits of Everest and the North and South Poles.

“All of this is technically possible,” said Jean Potvin, a physics professor at Saint Louis University and a skydiver who does parachute research for the Army. But he acknowledged a problem: “The thing I’m not sure of is your margins in terms of safety, or likelihood to crash.”

Loïc Jean-Albert of France, better known as Flying Dude in a popular YouTube video, put it more bluntly: “You might do it well one time and try another time and crash and die.”