Get your trebuchet on: Punkin Chunkin starts tomorrow

The annual Punkin Chunkin contest, which has become a fall rite for thousands, starts tomorrow as competitors gather in a Delaware cornfield to see whose machine can launch a pumpkin farthest.

Cast members from Mythbusters - Kari Byron, Grant Imahara, and Tory Belleci - will help host the event, which started in 1986 and is run by the World Championship Punkin Chunkin Association.

The goal of the organizers is to promote, "innovative engineering and science-based ideas." The Discovery Channel and SCIENCE channel will show the contest at 8 p.m. on Thanksgiving.

More than 30,000 are expected to watch the competition, which has grown in popularity each year and is held at the Wheatley Farm, on Sussex Highway in Bridgeville, Sussex County.

Last year, the event drew 72 teams and generated more than $100,000 in ticket sales and associated revenues.

Fans camp at the field and the machines begin launching pumpkins 8 a.m. Friday. The competition concludes Sunday.

The record toss is slightly more than 4,483-feet, and was set in 2008 by team "Adult Air Young Glory III."

Under the rules, the homemade machines are not allowed to use any explosives, and the pumpkins must remain intact until they strike the ground.

Proceeds from the event go to various charitable organizations, such as St. Jude Children's Research Hospital and Childhelp.