the_canuck: Western Colorado Slope Challenge 2008. Raw footage from my helmet cam setup. The planes are unpowered gliders. We use the wind shear created when wind passes over a sharp ridge to generate enough energy to fly. This was a contest. Yes, we are trying to knock each other out of the sky. there were over 30 pilots at the event which is held annually.The planes in the video are constructed out of EPP foam and are very durable.With more efficient planes, high speeds can be achieved with the DS technique. The current world record for composite type airplanes is 365MPH and 232MPH for foam type airplanes. See www.rcspeeds.com for current records.Andrewwww.canuckengineering.com