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Team Chucky stays on target to set world pumpkin hurling record

Chucky III can fling a pumpkin two-thirds of a mile at over 400 mph. [Image credit: GE Reports]

 

 

By GE Reports

Every November, GE molecular biologist Daniel Collins and his friends from Team Chucky haul a custom-made, 5-ton catapult to a field in Delaware where they take part in the annual World Championship Punkin Chunkin contest. Their machine, called Chucky III, can hurl a pumpkin more than two-thirds of a mile at over 400 mph.

Members of Team Chucky might be the pumpkin-chucking equivalent of the New York Yankees. They tend to dominate their field, but when they blow up, like they did this fall, they do it in style. "Several factors combined to give us the worst result we've ever had," Collins says. "The failures were spectacular, though. The pumpkins vaporized and basically ceased to be, with the exception of a fine orange mist that gently settled on nearby onlookers." The Science channel aired a two-hour special from the contest on Thanksgiving night. Collins talked to GE Reports managing editor Tomas Kellner about his pumpkin-chucking "obsession."

Tomas Kellner: The last time we spoke, you were aiming to cross the 1 mile mark. What happened this year?

Daniel Collins: We were dealing with subpar pumpkins, we used a new type of nylon rope for our torsion bundle that backfired on us, and a troublesome winch cut into our practice time.

TK: What makes a good chucking pumpkin?

DC: We evaluate pumpkins for their shape and density. You throw it on the ground as hard as you can and it must stay whole. Hard, small, and spherical pumpkins are the best. We have some friendly farmers who allow us to walk their private fields. But there is also an awful lot of horsetrading that goes on before the event. La Estrella pumpkins and the ghostly white Luminas are good candidates. They can handle a lot of G-force. Regular orange pumpkins wouldn't hold up.

TK: You mentioned a torsion bundle. What is that?

DC: Chucky III is a torsion catapult. It stores its energy in a twisted bundle made from 550 feet of rope that is one and a quarter inch in diameter. Two thousand years ago the Romans had similar designs. We twist the bundle with two hydraulic rams. When you are ready to shoot, you pull the trigger and the rope forces the arm to rotate.

TK: Is there a special kind of rope?

DC: We started with a polyester rope but switched to Nylon this year. That was a mistake. Nylon is stretchier, and we thought that we could get more power at the end of the stroke. But we were probably accelerating the pumpkins too much. All three of them exploded in the air.

We also did not get the machine tuned up because of the broken winch. At the competition we still did not fully understand how the rope was going to perform, and we had to adjust the rest of the machine to accommodate it.

TK: Why didn't you go back to your original rope?

DC: When we tried to unstring the machine, we found out that the Nylon rope all melted together and formed a big plastic block. It was a big mess. We had to cut it off. Next year we are going back to polyester.

TK: When do you start preparing for next year?

DC: We start in April and spend at least one day per weekend working. Come August, it's usually both days. It's a huge amount of time. The team has about half a dozen of core members, and others also help out when they can. Close to a hundred people came down to the firing line and camped with us this year.

TK: That's dedication.

DC: It's not an accident that we do well. We are clearly obsessed. We look at every angle we can. We are constantly improving the machine and making its safer, stronger, and simpler.

TK: What is your goal?

DC: We are in a class called torsion catapults. With the exception of this year, we usually win. None of the mechanical catapults can throw anywhere near 3,636 feet, which is our record. But our goal always has been to win the entire competition, including beating all the air cannons. This year, an air cannon set the world record at 4,694 feet. We know that we can beat these guys.

TK: What's the prize?

DC: When you win, you get to keep the big trophy for a year. It's a chainsaw sculpture of a bearded guy crouching over like Atlas with a big pumpkin on his shoulders. They put your team name on it and the year when you won it. It's sort of like the Stanley Cup.

Read more GE Reports at www.gereports.com

Published December 2013

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