The mountain in question was Tianmen Cave (pictured above) near Zhangjiajie City in China, nicknamed the Gateway of Heaven and regarded as the highest elevated natural arch in the world at 1,500m (5,000 feet).
Oh, and Jeb was flying on his own?
Not ‘on his own’ as in a solo flight in an aeroplane, helicopter or airship, or even just alone with a pair of glider wings and jet pack strapped to his back.
No, ‘on his own’ as in ‘he was flying by himself’ – no machines, no glider frame, no engines.
What the 35-year-old did have at his disposal was a wingsuit, a high-performance body ensemble that transforms you into something like a flying squirrel.
“You have nylon wings between you arms, nylon wings between you legs,” explains Corliss. “As you’re flying, instead of going straight down, you move forward three feet (0.9m) for every foot (0.3m) you fall. It gives you a glide angle so you’re no longer flying directly towards the ground, you’re flying on a slope."
“Flying across Tianmen Mountain was the most challenging task in my life. I have visited and investigated many places, but there's no place like Tianmen Mountain.”
Jeb’s ‘investigations’ have seen him BASE jump – i.e. deploy a parachute after leaping from a fixed object – from the Seattle Space Needle, Venezuela’s Angel Falls, the Eiffel Tower and the Golden Gate Bridge.
Earlier this summer in Switzerland, Corliss became the first man to fly through a waterfall wearing a wingsuit as he engaged in some white-knuckle ‘proximity flying’ – the risky yet spectacular technique of gliding close to the face or ridges of hills and mountains.
In China, Jeb started his Tianmen Mountain flight by jumping from a helicopter before eventually deploying a parachute to land – currently the sole method available of bringing a wingsuit outing to a safe conclusion.
But that will change if Corliss gets his way. The Wingsuit Landing Project is the Californian’s ongoing quest to be the first human to leap from an aircraft and land without a parachute.
“The attempt is to jump from an aircraft, reach terminal velocity and then make a non-parachute landing,” he says. “The hard part is to survive uninjured."
“A wingsuit landing will only be successful if you can do it 10 times out of 10 without being injured. I’m talking no broken toes, no broken anything.”
A wingsuit could potentially slow a vertical descent, albeit briefly, to about 50km/h (30mph) – a massive reduction on the usual 180-225 km/h (110-140 mph).
But the pilot would still be moving forward horizontally at 120 km/h (75mph) at least – more likely at a considerably faster speed – meaning any faulty movement would lead to a fatal crash.
So what does Jeb have in mind to increase the likelihood of a soft landing?
Well, he’s fairly tight-lipped about his plan as he isn’t the only one obsessed with making history. Other wingsuit pilots around the world – Frenchman Loïc Jean-Albert and Brazilian Luigi Cani, for example – are also plotting to perform the first ever non-parachute landing.
But Corliss has hinted at constructing a custom-built runway while also talking about attaching his helmet to a rigid-framed exoskeleton
Writing on science and technology website Popular Mechanics, journalist James Vlahos has made a good stab at guessing how Corliss might pull off the stunt and it’s worth checking out here: www.popularmechanics.com/technology/aviation/diy-flying/how-to-land-in-a-wingsuit-sans-parachute
Vlahos reckons he will most likely try to land like an Olympic ski jumper, matching the angle of the slope as closely as possible, though Corliss will be hurtling along at nearly twice the speed and will try to land on his front, not on his legs.
“This is something people have wanted to do since the story of Icarus,” says Corliss. “In this day and age it’s hard to do something that has never been done before."
“This will be the first time a human being has reached terminal velocity and landed on their face at over 110mph (180km/h) and gotten up and done it again. That’s a very special thing.”
Indeed it is, as is the cost of constructing such a runway: about two million dollars.
Corliss adds: “Everyone thinks this is so impossible, you can’t do that. Well, the only reason you think it can’t be done is because you haven’t done it. I believe I can and that’s probably why I am going to.”
Watch the video above for an idea of what it's like to fly along the ground. Landing without a parachute is the hard bit!