What is it with men wearing nothing more than some flimsy fabric between their legs and arms flinging themselves off very high objects?

Forget Felix Baumgartner, this week's craze is the Red Bull Wingsuit Flying World Championships

Intrepid daredevils in China jump from the top of the mountain 1,400 meters up before completing a lap of the valley in the fastest possible time, reaching speeds of 140 mph.

Obstacles include a potentially decapitating cable car line strung across the valley not to mention rocky outcrops, trees and that perennial threat to every wingsuit flyer, the ground.

If all goes well they land at the finish line marked out on a mountain road, if not, well, that doesn't bear thinking about.

15 competitors are taking part with American, Jeb Corliss, favourite to take the title.