Physics Students Model Airplane Design Challenge 2010 By Bill Kuhl Early January of 2010 I helped a science teacher friend with an assignment for his physics students to design, construct, and fly a rubber powered model airplane. I helped for two class sessions; the first to show sample planes I had built and explain design approaches such as hi-aspect ratio, dihedral, winglets, target weight, and wing area. Students were given suggested formulas for sizing the surfaces based on the wing area. I then returned the end of the week to help with the flying. Two variations from the basic Denny Dart design. Examples Hi-aspect ratio version of Denny Dart in flight. I brought a Squirrel model plane for show but this one was built by the designer, Darcy Whyte. Students built their planes on cardboard, I prefer to use ceiling tile. Building Hi-aspect ratio wing with under-chamber airfoil, at least a couple of the students took this approach and their planes flew well. Wing tips were extended behind the rest of the trailing edge. This student forgot the vertical fin, hopefully that was corrected. This student built a smaller plane with high-aspect ratio and tip dihedral. FFlying These students were very good about working together, and traded off being the stooge while the plane owner did the winding. A couple of years before this, the physics students were given the same assignment but they had less instruction on what was important for a good flight. There were many clever ideas, but not many of these planes flew very well. Flying wing on the left must have been influenced by the Stringless Wonder. Planes on the right were too heavy for the rubber and propeller used. The biplane might have flew if there was not so much curve in the airfoil which caused too much drag. Very interesting twin motor design, with more stability it might have flown well.