US daredevil films 100mph flight through 4-metre-wide mountain valley in a wing suit

Wingman Jeb Corliss calls it 'the hardest thing I've ever done'

You might need to watch this footage through your fingers: it shows a bat-winged daredevil leaping from a helicopter and through a narrow mountain fissure.

The 37-year-old base-jumper Jeb Corliss flew in between a crack in the 900-ft tall Langshan Mountain, Zhejiang Province in China, at a gut-wrenching 100mph. He successfully completed the “Flying dagger” jump with expert precision, despite the widest point of the gap being only 20 metres wide, and 3.5 feet at its smallest.

“This is the greatest thing I've ever done up to this point. I am just so, so happy that we were able to do it,” he told reporters after the jump.

“I was really worried that it wasn't going to happen. I was sure it wasn't going to happen. I've no idea. I just didn't want to disappoint everyone.

”The Chinese have been so nice to me. The Chinese government has been so wonderful. I just didn't want to disappoint everyone.

“I am really glad I was able to do it, because it was so hard. This was so hard. This was really, really, this was the hardest thing I've ever done.”

Corliss has been skydiving since he was eighteen, and has jumped off famous landmarks including the Golden Gate Bridge, the Eiffel Tower and Angel Falls in Venezuela.