|Entry #||Driver Name||Car Name||Mass
|3||3||Dean/Debbie Oisboid||DD Mean Machine||18||11||13||4.5||15.25||1.12||Fastest|
Balloon car designers Dean and Debbie Oisboid write:
The DD Mean Machine was an elastic-powered balsa airplane. Off-the-shelf model. (Faster, better cheaper?) Yes, Virginia, it was a legal racing vehicle. Since it began the race on the ground and ended on the ground, it met all the requirements of the contest.
The name was chosen, with apologies to Messers Barbera and Hanna, in honor of Dick Dastardly and Muttley's vehicle. They, too, managed to honor (most of) the rules of their races.
Each balloon was sliced in a zig-zag pattern to provide a 1/2" x 20" strip of rubber, which was then tied closed to form a loop. These two loops hooked onto the plane (in parallel) in lieu of the provided rubber band. (Four lengths of rubber total between hooks.) Before winding up the propeller, the bands were coated liberally with baby powder to help them untwist without sticking.
It was hoped that by providing elastic loops longer than the distance between the attachment hooks on the plane, that it would allow the propeller to unwind more than it was wound up. This did not occur. The powder only helped marginally; the balloons still stuck together and did not fully untwist. (Perhaps caused by initial overtwisting?) In the future, perhaps a different lubricant would be used. Or perhaps the balloons might not be sliced.
It was also hoped that the vehicle would become airborne and eliminate any friction factors. This also did not happen during the race, although it did succeeed during several trial runs. The vehicle frequently skewed sideways during trial runs and paper tabs were added to the wings in the hope that that would help straighten out the path. While this was not seen during the official run, after plopping into the water on a second attempt the vehicle not only went in a nearly straight line, but also lifted one wheel off the ground! This third and unofficial run was approximately 27 feet.