It is possible to create freestyle versions of paper aircraft, which often exhibit an unusual flight path compared to more traditional paper darts, jets and gliders. Another propulsion technique, creating high launch velocities, involves the use of elastic bands for "catapults". Walkalong gliding involves the continuous propulsion of paper airplane designs (such as the tumblewing, follow foil[9] and paper airplane surfer[10]) by soaring flight on the edge of a sheet of cardboard.