At a Glance: Students build a foam wing glider by using a hot-wire foam cutter to form wings into an airfoil shape and building the fuselage and tail section from balsa.
Concepts:
Students discover the lifting properties of airfoils provides an excellent opportunity to discuss Bernoulli's principle. They also experiment with wing dihedral and weight distribution.
Details: Students trace patterns of a glider's fuselage and tail sections, wing supports, and horizontal and vertical stabilizers onto a sheet of balsa and cut them out using a hobby knife. The pieces are sanded and glued to each other to form the glider's body. The pattern for the upper and lower sections of the airfoil pattern are traced onto cardstock, cut out with scissors, and sanded smooth along their edges. (The shape of the wing [airfoil] may be designed or copied from examples provided.) The patterns for the wing are attached with straight pins to the end of an 11-cm by 23-cm block of polystyrene foam. Then, the foam block is mounted on the Pitsco Foam Wing Cutter, an electronic device that gently pushes the foam into a hot wire that follows the shape of the pattern, cutting the foam and producing a wing with the desired shape. The process is repeated for the second wing.
After carefully sanding the surfaces and edges smooth, the ends of the wings are positioned together to form a dihedral angle, sanded to fit snugly when joined, and then glued together to form the wing section. The wing section is glued to the fuselage and allowed to dry for one hour. When the glue is dry, students test the balance of their plane, affixing modeling clay to add weight where needed to achieve balance. Then, the glider is ready to test. If the plane dives, stalls, or experiences other performance problems, students make adjustments to achieve maximum performance from their plane.
At a Glance: Students build a foam wing glider by using a hot-wire foam cutter to form wings into an airfoil shape and building the fuselage and tail section from balsa.
