Pumpkin Launching

By Mark Robichaux
Staff Reporter for The Wall Street Journal

     MORTON, Ill. -- Ponder this: Will a pumpkin, as it nears the speed of sound, turn into pie in the sky?
     In a machine shop in a sea of cornfields here in a place that calls itself the Pumpkin Capital of the World, this is not a theoretical question. For months now, a team of volunteers has worked earnestly on an effort to send a gourd soaring at Mach I.
     Their invention is an 18-ton, 100-foot cannon made of 10-inch-diameter plastic pipe, powered by compressed air and mounted on an old cement mixer. Dubbed the Aludium Q36 Pumpkin Modulator, it has already set a world distance record, flinging a pumpkin 2,710 feet -- at a velocity of more than 600 miles per hour, literally faster than some speeding bullets.
     At the speed of sound, minimally about 750 mph, the distance record could easily be shattered, assuming the pumpkin doesn't shatter first. For this team of self-described "high-tech rednecks," this is a matter of some urgency and pride, says Matt Parker, a Morton businessman and a team leader. For the team is, at the moment, the undisputed champion of the arcane sport known colloquially to its practitioners as "punkin' chunkin'."
     On Nov. 1, all eyes will be on the Q36 when it defends its title as World Champion Punkin' Chunker in Lewes, a small town on the Delaware coast.
     For the past 11 years, pumpkin tossers, dragging all manner of contraptions, have converged there to vie for bragging rights in a variety of pumpkin-tossing categories -- human powered, centrifugal, catapult and air cannons. Sponsored by the Roadhouse Steak Joint, a Lewes restaurant, the contest derives from an anvil-throwing game once played here; how the anvil evolved into a pumpkin seems to be lost to history.
     The modern contest's rules are clear, however: Pumpkins must weigh 8 to 10 pounds, leave the machine intact and not be propelled by explosives.
     Like the rapid advance in, say, computer technology, pumpkin-tossing prowess has improved exponentially since the first contest in 1986 produced a throw of 50 feet. By 1989, large-scale centrifugals, essentially giant slings, were launching pumpkins more than 600 feet, a mark that had doubled by 1993. In 1994, the first serious air cannon appeared and shot a pumpkin more than 2,500 feet. A Delaware-made air cannon named the "Mello Yello" beat that mark with a 2,655-foot shot in 1995, only to be bested by the Q36 last year.
     Of course the cannons, though they have the longest range, don't attract all the attention. Last year, a catapult competitor rigged up two telephone poles planted in the ground, fitted huge rubber bands to them and fired a pumpkin from this Paul Bunyanesque slingshot -- pulled taut by a power winch -- 493 feet.
     Still, the serious pumpkin tossers gravitate to the cannons, and here in this small Illinois town, pumpkins are serious business. Area farms supply about 80% of the nation's canned pumpkin through Nestle SA's Libby's plant here. When the chamber of commerce director, Scott Witzig, heard about the Lewes contest in early 1996, he issued a call to arms at the chamber's annual dinner: Build a gun to bring honor to Morton's pumpkin heritage.
     The challenge was taken up by Mr. Parker, a polite, 28-year-old vice president at Parker Fabrication Inc., a family-owned company that builds industrial-exhaust systems. Soon, he and some tinkering friends were swapping sketches on napkins in coffee shops. "It sounded kind of dumb at first," he says, "but pretty soon, that's all we talked about."
     In a month's time, a group formed and built a machine largely from scrap parts, often working into the early morning at the shop of Rod Litwiller, a crew member. Friends and neighbors stopped in to help. Only when a crude version of the machine was unveiled at the Morton pumpkin festival in September last year did the builders get an idea of the machine's power.
     The first shot flew out of sight into a cornfield. "We thought, 'This has potential,'" says Chuck Heerde, a 32-year-old Parker employee and crew member.

High Expectations
     The Q36, when erected, resembles a crane. It is hand-loaded from the rear, aimed using hydraulic cylinders and a turret that was once an old cement mixer and fired with the push of a red button that releases a charge of compressed air. Painted military green, the gun was named after a weapon used by Marvin the Martian, a pint-sized alien in a Warner Brothers cartoon.
     Ferocious as the Q36 looked, the Morton pumpkin crew still wasn't sure what made a pumpkin fly farthest. Too much pressure too fast, and the pumpkin bursts apart in the barrel. Too slow, and velocity suffers. Pat Parker, Matt Parker's father, contacted Max Teasdale, a friend who teaches engineering mechanics at Bradley University in nearby Peoria. An avid skeet shooter, Mr. Teasdale said he had just completed a ballistics analysis of shotgun pellets. "I asked him: 'Can you modify that for a 10-pound pumpkin?'" says the elder Mr. Parker. "He was silent for a second. Then he smiled."
     Mr. Teasdale modified the ballistics program to compensate for a pumpkin flying through an 80-foot barrel in hopes of plotting the best trajectory. The computer tabulates, among other things, the weight and number of sections in a pumpkin (usually 10), the pressure and temperature of the air in the tank, the barometric pressure, pumpkin spin and barrel inclination. Still, Mr. Teasdale concedes that "pumpkins are an unreliable projectile."
     Undeterred, the Morton crew packed up the Q36 and hitched it to "The Blackbird," a black and silver GMC bus fitted with a diesel engine and front end welded together by Mr. Heerde. When the Q36 rumbled into the fairgrounds in Lewes for last year's contest, however, more experienced cannon makers were prepared to blow it off. But, after its first pumpkin blew apart in the barrel, the Q36 blew the competition away. Its winning shot of 2,710 feet broke the existing record by 55 feet.
     It also narrowly missed a Ford Mustang in the parking lot. This could have been serious: In a demonstration earlier in the day, the Q36 had blown a pumpkin-size hole in a half-inch thick sheet of plywood 500 feet away.

Giving No Ground
     Word of the Q36 has spread like pumpkin butter. On the Punkin' Chunkin' Web site, one reviewer called the debut of the Q36 "awe-inspiring." Harry "Captain Speed" Lackhove, a Delaware competitor whose Mello Yello cannon held the previous world record, has vowed to come out of retirement to challenge the Q36 at this year's contest. Mr. Lackhove, 72, says he is cooking up a high-tech firing device based upon the designs of a California race-car mechanic and predicts, "We expect to set a record that won't fall for years." Which is why the Q36 crew vows to send a pumpkin flying at Mach I soon. But Mr. Teasdale, the physics professor, tempers the crew's ambitions with reality. Compressed air and computer-aided trajectories can send the pumpkin sailing just up to the sound barrier, he says. But he doesn't think it can be broken without the boost of an explosive charge. And no one quite knows if a pumpkin can stay intact at the speed of sound.
     Still, practice makes perfect. On a recent fall afternoon, the Q36 crew took the cannon to Goshen, Ind., for a rare public demonstration at the grand opening of a subdivision called Clover Trails. A horn sounded across the cornfields as the barrel of the Q36 rose ominously and, with a loud "foop," fired a pumpkin. This was a low-power shot, and it sailed perhaps 1,200 feet. Soon, cars pulled over and a crowd of about 100 materialized. Loud applause and laughter erupted after every shot.
     Between shots, a farmer walked up and asked, "How far can she go?"
     "We can put a hole in that silo over there," said Mr. Heerde.
     "Oh, don't do that," the farmer said. "That's my silo."

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