ASPEN, Colo. (AP) – Chris Burandt squeezed on the throttle as he barreled toward the ramp, ready to pull off a trick he had never tried. But he couldn’t make himself do it.

Over and over, Burandt started up the ramp, then bailed out at the last second, easing off the gas as he hit the lip. Finally, after nearly two dozen attempts, Burandt got the speed and his nerves just right, launching his snowmobile, pulling on the handlebars and completing the backflip. Athletes at the Winter X Games are known for their bravado and I-can-do-anything attitude, but the newest event at the action sports showcase, freestyle snowmobiling, is way up the gnarly scale, making even one of the world’s best all-around snowmobilers squeamish.

“I bet I was out there for an hour with everyone out there watching and waiting and filming, and I just couldn’t tell myself to do it,” Burandt said. “I finally got it into my head that there was no way I had a chance to win the X Games without a backflip, so I just did it. It’s very intimidating.”

What makes freestyle snowmobiling such an off-the-hook event – and so perfect for the Winter X Games – is that 400-pound machines doing backflips in the snow just doesn’t look right or even seem physically possible, like seeing a dump truck hit 200 mph on a NASCAR track.

The riders modify their sleds, stripping down all the excess weight, some of them carving out the sides of their seats to get a better grip with their legs. Still, it’s basically someone doing a backflip in a Geo Metro.

Then there’s the sound. If you can imagine a freight train crashing to the street from a 10-story building, then you get an idea of what it sounds like when one of those sleds hits the snow. And that’s when they land the jump. It’s even worse when they don’t, the cracking fiberglass, crunching metal and fearful groans from the crowd forming a symphony of destruction.

Yes, freestyle snowmobiling is very dangerous.

Three years ago, moto X rider Brian Deegan crashed while attempting a backflip with a full twist at the Winter X Games. He bailed out of the trick halfway through and fell from 35 feet, landing with a thud on the ice below. Deegan broke his pelvis and both wrists in one of the worst crashes in the games’ 11-year history, but it could be much worse if one of the snowmobilers wipes out and gets crushed by a sled.

Several riders crashed hard during practice runs Thursday, including one who went face first into the snow after failing to rotate his sled around on an attempted backflip. There was one trip to the hospital for a suspected broken back (X-rays came back negative).

and another rider who might have broken some ribs. Thankfully, there hasn’t been anything more serious, but the finals aren’t until Sunday.

Of course, the combination of sight, sound and the carnage is what has made it such a big hit with the fans.

“It’s one of the most amazing things I’ve ever seen,” Ted Stevens of Minneapolis said during Thursday’s practice session. “It’s unbelievable that these guys can flip machines that big.”

Freestyle snowmobiling got its start a few years back when some of the racers got bored with going around in circles, so they started jumping anything they could find – even houses.

Following the lead of the moto X riders, freestyle snowmobilers kept pushing the boundaries of their sport, kicking their feet off over jumps, letting go of the handlebars, eventually pulling those sleds around for backflips.

Motorcycles on snow never did seem to be a good fit – there were too many weather variables and the riders never got to practice on the white stuff – so organizers scrapped moto X this year in favor of machines made for the winter.

“When you look at a lot of things that they do, they take a lot of their tricks from the moto and it seemed like a good time and a natural progression to take the motorcycles off the snow and put the snowmobiles on the snow,” X Games general manager Chris Stiepock said.

It was great news to riders such as Burandt, who had been doing their tricks in relative obscurity. Flipping snowmobiles on the biggest stage in action sports is sure to attract attention, which can only progress the sport further.

“What I’m hoping to see is to have this be an eye-opening experience for a lot of up and comers because that’s the one thing we really don’t have,” Burandt said.

“You go to a motocross and there’s 50 dudes throwing sick, sick stuff, but really we don’t have that type of talent pool. And we need that to get people into the sport and I’m hoping X Games can kind of exploit what we’re all about.”

AP-ES-01-26-07 1741EST