How to Build a Bullet

Aband of gunmetal mountains rings one side of the Bonneville Salt Flats. In the opposite direction, the desert floor stretches uninterrupted into the distance, all the way to where the ice-white salt fades into hazy blue. It is a place without boundaries, a proving ground for unbridled speed. But Bonneville is also a place where the list of things that can go wrong far outnumbers those that can go right. For a team of young engineers from Ohio State that plans to test the limits of technology with a battery-powered rocket car, that list is nearly infinite.

For starters, the Venturi Buckeye Bullet 3 could fail to start. It’s a 7,800-pound Rubik’s cube of metal cages, carbon fiber, battery packs, and motors, all hooked into an endless constellation of wiring – it’s a minor miracle it ever powers up. Once it’s scorching across Utah’s flats, an irreplaceable part could break. Or a parachute – the primary stopping mechanism – could fail to deploy correctly. The cooling system could malfunction, causing increased temperatures that would transform the neodymium rare earth magnets in the motors into ultra-expensive, worthless paperweights.

Or it could rain.


There are two things you need to know about this Bullet. First: its three previous models claim the most meaningful speed records for electric vehicles. Every battery-powered car to break 300 mph had a Block “O” emblazoned on its hull. Second: the Bullet 3 retains only two pieces of equipment from earlier versions: the tires and the driver.

But long before the Venturi Buckeye Bullet 3 was a 38-foot monster, it was an idea sketched onto a napkin. In 1999, the Formula Lightning Series for university-sponsored electric vehicles was headed for extinction, and the Smokin’ Buckeye team, which had won every single national championship, needed a new challenge. Dr. Giorgio Rizzoni, the new director of Ohio State’s Center for Automotive Research (CAR), arrived that same year, and the Bullet project offered an ideal platform for his aspirations.

“The vision 15 years ago was to make people basically say, ‘The Ohio State University has the best automotive research center in the country,’” Rizzoni said. “No one would ever put Ohio State anywhere but in the top three, okay. And I think number three is ridiculous.”

CAR was a $1 million venture at the time, but under his leadership it has grown exponentially, projecting financial support of about $13 million for this year. Six student teams operate from the center, including the Bullet – nearly all of which is designed, built, and assembled by coeds.

“The minds behind the effort will change the automotive industry,” Rizzoni said.

One such mind is that of David Cooke, a mechanical engineering grad student who serves as the technical manager and sixth-year team leader for the Bullet project. The team consists of four to five core students and another 10 to 20 volunteers who help as they can. Since his freshman year in 2004, Cooke has taken a circuitous route through college, extended by rotations with Honda R&D and a six-month stint with the French automotive company Venturi.

Collaboration with industry partners is one of the biggest benefits for CAR students, as they build relationships that often lead to jobs after graduation. In addition to promoting next-generation talent, the Bullet project also serves to stress-test systems that could change the everyday automotive landscape.

“Not everyone is going to fly Virgin Galactic to Mars, okay, but some of the things that the space program has done we have in our vehicles today,” Rizzoni said. “So it’s just pushing the edge, finding the extreme limit of performance of every component in the vehicle.”

Thus, the natural evolution of the Bullet as spurred by its creators – further, faster.

“What happens with these guys is that they have never failed because they’re just learning how to do things,” Rizzoni says of CAR’s young engineers. “But this thing about never having failed is the greatest asset they have because to them the world is a limitless place.”


There may be no boundaries, but there are skeptics. Despite enviable achievements, the Bullet team still has something to prove to the speed freaks at Bonneville.

“They always go, ‘Wow, 300, that’s really fast… for a group of students,’ or, ‘Wow, 300, that’s really fast… for those electric cars,’” Cooke says, his voice dipping for the qualifiers. “So what we all started to ask ourselves was how do we get rid of those labels and just say, ‘Wow, that’s really fast.’”

What that means is 400 – one mile every nine seconds, less than the time it takes Usain Bolt to run 100 measly meters. Breaking 400 would make the Bullet one of the fastest dozen wheel-driven vehicles the world has ever seen, regardless of power source.

And so a reinvention was in order. It began with the concept, years in the making, evaluated from every computer-generated, software-simulated angle imaginable. Then it was on to prototyping and component-level testing – tires, batteries, motors, etc. Systems testing came next, and then finally driving the vehicle to work out the kinks.

Now the nearly completed Bullet sits to one side of CAR’s student-project warehouse. The carbon fiber shell hangs from wires like animal skin; the mechanical body rests like a carcass below. Tubular metal bones protect the innards – tangles of cables and massive shiny black batteries. The cockpit is ripped from an Indycar frame and customized to fit the only man who ever drives the Bullet, Roger Schroer, a professional racecar driver from the Transportation Research Center (TRC) in Marysville.

Schroer is the man in harm’s way should any one of the myriad problems strike while the car throttles across the desert. The Bullet has triple redundancies for every safety apparatus, including three separate parachutes and an aerospace braking system that can stop the Bullet from 300 mph – auto brakes would turn to liquid attempting to halt a vehicle of its magnitude from any speed over 60.

Nothing that moves like the Bullet can ever be perfectly safe, though, which Cooke acknowledges by quoting one of Schroer’s favorite self-deprecating mottos: “The best drivers have a small helmet and a big shoe.”

No matter the size of the shoe or the weight of the foot, TRC has just enough space to bring the Bullet up to about 100, sufficient to test functionality but not nearly enough to let the beast stretch its legs. And that’s why, although its predecessors eclipsed 300 multiple times, all the team can say for sure is that the Venturi Buckeye Bullet 3 will go about 100 mph.

“I should be able to report back to all the people asking how I’m spending their money and say, ‘This is what we’re gonna do,’” Cooke explains. “At Bonneville, if you walk in the first day saying, ‘This is what’s about to happen,’ you’re guaranteed it won’t happen.”


Before Bonneville was a desert, it was a lake, and every fall it reverts to its previous state for most of the next three seasons. The window for land-speed racing on the Salt Flats usually lasts about two months, August and September, give or take. Last September, right when the Bullet 3 arrived for its first chance to flex, the rains came – the earliest in 80-some years.

“Lake Bonneville,” Cooke says with chagrin. The water stood a foot deep on the race surface. Then as the heat settled in, it moved back into the mountains, retreating up to 20 miles a day, and each night the team thought that the next morning would allow racing to begin. And then the rains returned, day after day for two weeks.

So they took residence in an airport hangar nearby and programmed and tweaked and waited. They used one of the runways for testing, but they were still capped at about 100 mph. Finally they returned to Ohio with the Bullet, unproven.

Cooke admits that the car wasn’t ready to go 400 last year, given the unfamiliarity with their brand-new drives, one for each of the four motors. Even if they had the opportunity to let it rip, the process takes time. They start with a known, say 100 mph, and incrementally push up the speedometer, usually by only 25 mph each run. They manage just two runs per day at best, meaning the process of working into the faster reaches of the unknown, say 400, takes weeks.

Each voyage down the seven-mile track is a study in risk and safety, a balancing act of possibility and mechanical reality, monitored and scrutinized via hundreds of sensors. How was the temperature? Is there a problem with the aerodynamics? Did anything, anything at all, give them an indication that something may go wrong?

Is this the run?


They will return to Bonneville in August. And then, if everything goes as planned, the Bullet will shoot across the earth, hurtling closer and closer to the horizon, that untouchable place where salt meets sky.

To learn more about the Venturi Buckeye Bullet 3, visitwww.buckeyebullet.com/index.html, and for more about the Center for Automotive Research at Ohio State, visit www.car.eng.ohio-state.edu.

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