A small section of the Whistler sliding track acted as a ramp that launched Nodar Kumaritashvili high enough to sail over a retaining barrier and into a steel support post at the 2010 Winter Olympics in Whistler, an American professor suggests in an interview with the fifth estate that will air Friday on CBC-TV.

For the past three years, the fifth estate has been investigating how and why the young Georgian luger died at the Vancouver Olympics. The new scientific findings from a leading expert on sports biomechanics may now finally explain why Kumaritashvili was thrown off the track.

"The forces that were applied to the right runner of the sled, early in the interaction with this rounded fillet, provided very large vertical forces," says Mont Hubbard, a professor of mechanical and aerospace engineering at the University of California in Davis.

"And those are the forces required to shoot, to give him upward velocity and to allow him to pass over the wall."

The fillet, as Hubbard calls it, is the curved joint of the track where the sidewall meets the floor.

The Georgian athlete's luge sled hit the fillet at the inside wall at the end of the last curve after coming down high from the outside wall.

He was travelling at a speed of 144 kilometres an hour.

Watch Watch the fifth estate documentary, The Last Race on Friday. It airs on CBC-TV at 9 p.m. (9:30 in Newfoundland and Labrador).

The official explanation from the International Luge Federation has always been that a "catapult" effect launched him out of the track, that his sled compressed and then acted like a spring.

Hubbard says Kumaritashvili's sled did compress, but after he acquired the vertical velocity for launch.

"He was already essentially launched," says Hubbard. "When the catapult happened, he already had that velocity, and it was caused by running up on the fillet and — yep, vertical forces."

First scientific analysis

Hubbard's research, to be published in the international journal Sports Engineering, is the first scientific analysis of the deadly crash that was the low point of the 2010 Winter Olympics.

The B.C. coroner's report makes no conclusion how Nodar Kumaritashvili's luge sled was ejected from the Whistler track. Eric Foss/CBC News

"I waited for the FIL [International Luge Federation] report to see what their explanation of the event was going to be. When it was a non-explanation, in some sense, that's when I decided to model the interaction of the luge with the fillet," says Hubbard "Because the amazing thing is that this accident was on video, and you can't not see that the right runner is interacting with the fillet, it's right there in front of your eyes."

The publishing of Hubbard's research comes on the heels of the December release of the Whistler safety audit, which was recommended by the Coroners Service of British Columbia in its report into the death of Kumaritashvili.

Section 5.5.4.3 of the audit says it did evaluate Kumaritashvili's crash and "analysis was conducted to identify the interaction that resulted in the vertical velocity motion of the slider."

But Hubbard says that analysis of vertical velocity is not in the safety audit, and it should be.

"And that's a glaring absence, I think. Given the fact that accident is the reason the audit happened," says Hubbard.

"That was not the intent of the study," says Alex Zahavich of SAIT Polytechnic in Calgary, the principal investigator on the safety audit in an interview with the fifth estate's Bob McKeown.

"We were not there to determine what happened because that is the assignment of the cause of the accident, that would be determined by the coroner."

But the coroner's report makes no conclusion how Kumaritashvili's luge sled was ejected from the track.

In his call for the safety audit, the coroner specified that it should address the possibility of "sleds leaving the track".

"For the audit not to have it in the main body of its report, some precise, careful description of how that ejection happened is curious," says Hubbard.

The International Luge Federation declined to be interviewed by the fifth estate about the role of the fillet in Kumaritashvili's crash. The organization instead directed CBC News to its online rule book, where there is no mention of fillets.

"I believe the fillet is the proximate cause of ejection," says Hubbard. "Because if the fillet hadn't been there, I believe ejection could not possibly have happened because there isn't any way to get the vertical velocity you need without that fillet. There's simply no way."

Watch the fifth estate documentary, The Last Race on Friday. It airs on CBC-TV at 9 p.m. (9:30 in Newfoundland and Labrador).