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Make it or break it
Robert F. Jones
September 02, 1974
Millions are at stake and a life is on the line for one shot across the canyon
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September 02, 1974

Make It Or Break It

Millions are at stake and a life is on the line for one shot across the canyon

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"The more I studied on it, and the more Montana Marys I put back, the narrower that durned hole in the ground seemed to get," Evel recalls. "People talk about the Generation Gap and the Missile Gap and the Education Gap, but I suddenly saw that the real gap was right out there in the heart of the Golden West. And I knew I could bridge the bastard."

It was then and there that the monster was born.

Later, when the U.S. Department of Interior denied him airspace over the Grand Canyon—on the grounds, apparently, that national parks are not meant for the suicidal self-aggrandizement of the citizenry—Evel shifted his sights to Idaho's Snake River Canyon. It is not the same thing, of course, either symbolically or in terms of size. Where the Grand Canyon measures from four to 18 miles from rim to rim, and up to 5,700 feet in depth, the Snake River Canyon, at the point where Evel will jump, is less than a mile wide and 600 feet from the crumbling lava of its lip to the turbulent water below. Nonetheless, it's a long way over and a long way down—potentially fatal distances any way you look at them.

The plan, as it first exploded in Evel's fecund imagination, was-to jump with a real motorcycle to which some form of additional propulsion would be attached, maybe JATO bottles, maybe a steam-powered booster rocket. Evel imagined himself roaring up a long approach road toward a ramp much like the ones he uses in his automobile and truck leaps. Millions would line the road, their cheers drowned out by the bellow of the big hawg. At the last moment the booster would ignite, kicking Evel and bike into a long, high trajectory. On the far side, if he could hold it, he would touch down on a landing ramp.

It didn't take long to realize the impossibility of that dream. It would have to be a modified rocket shot if it was to work at all. "I started hunting for a rocket guy," Evel says, "the best one that money could buy. Finally Jim Lovell, the astronaut, told me about a fellow named Robert C. Truax who was one of the founders of Nassau"—that's NASA to non-Montanans—"and who'd worked on the big space stuff right from the start. He was so excited by the idea that he dropped everything and came to work for me."

Truax had worked on a lot of the big space stuff, all right, but not for NASA as Knievel says; the engineer was once president of the American Rocket Society and conducted studies that led to the Polaris missile. In any event, Truax proved to be invaluable to the scheme: his down-to-earth aerospace sense perfectly counterpoints Evel's soaring imagination. A short, taciturn man of 56 with a salt-and-pepper crew cut, he has done his best to ensure that the safest possible vehicle would be built for the price Evel was willing to pay. Still, it might not be enough. Evel claims to have spent $1 million on the Sky-Cycle and the launch site, including $37,500 to lease the land surrounding the takeoff ramp and thus preclude any further governmental interference. For all that, one wonders if enough has been spent to ensure a successful jump.

If it has, then Bob Truax is in for a nice bonus. Evel carries a check for $100,000 made out in Truax' name. Significantly, it is dated Sept. 9—the day after the jump. "That way if I don't make it," Evel says, "Bob doesn't either. Heh, heh."

The way it now looks, Evel will take off from a standing start at the bottom of a 108-foot-long steel ramp angled at 56 degrees above the horizontal. The Sky-Cycle's steam jet, which should be "safer" because it uses nonvolatile fuel, will generate 5,000 pounds of thrust, enough to fling Evel at the speed of 400 mph to an apogee 2,000 feet above the takeoff point. During the liftoff he will pull in excess of five Gs—not enough to cause a blackout but maybe enough to give him a bloody nose and render him non compos for four seconds, according to Truax. He will not wear a G suit, not even one of the sort worn by test pilots as long ago as World War II. Instead he will don a special star-spangled red, white and blue knit jump suit complete with crash helmet. The cockpit itself is open and makes the Sky-Cycle seem more like a motorcycle, which it is not by any stretch of the imagination. It doesn't even have a steering system, for that matter, though there is a sort of fixed handlebar for Knievel to cling to. This will be, plain and simple, a ballistic trip, with Evel along as the passenger.

To ensure that involuntary movements of the rider do not throw the vehicle out of whack and send it tumbling during its trajectory, and to keep him from being thrown forward, Evel will be strapped in with lap and shoulder harnesses. There is no ejection system in the craft; if Evel has to hit the silk, he will have to scramble out and over the side and unleash his parachute. "If he gets warning soon enough that the vehicle chute isn't working—and if he works fast enough—he can get out with the reserve chute," says Truax. At the low altitudes involved in the shot, such action calls for a lot of luck.

Toward the end of the trajectory, which is computed to cover 4,781 feet horizontally, Evel will pull a lever at the right front of the cockpit that will deploy a drag chute from the rear of the Sky-Cycle. That will drop the vehicle nose first into the sagebrush where shock absorbers will dampen the impact. (One envisions the Sky-Cycle bouncing across the desert at the end of the ride like some fat, finned and star-spangled pogo stick.)

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