GRADES 9-12
AERODYNAMICS OF A BOOMERANG

BACKGROUND INFORMATION: Boomerangs are constructed in a wide range of shapes and materials. Boomerangs are designed with specific performance characteristics in mind such as LD (long distance), MTA (maximum time aloft), accuracy, and ability to return. Additionally, certain materials are best suited for children or a beginner due to weight and safety factors. The angle between the wings may be altered to change performance characteristics. For example, a sharper angle would decrease the tip speed, making the boomerang easier to catch. A modern boomerang might have several wings joined at a common juncture. Alternatively, a boomerang might be fashioned to represent an object like a bird or straight-edged razor. There are even boomerangs shaped in the form of the letters of the alphabet. All of these boomerangs use the same principles discussed to return to the thrower at the end of its flight. There Are Different Types Of Boomerangs With Permission and Courtesy Of Cislunar Aerospace, Inc. Today, a vast array of materials are used in the construction of boomerangs - from tropical woods to computer circuit boards. Material is selected based on the type of boomerang, its range, intended use, cost, as well as tooling and health and safety risks involved in the usage of the materials. Early boomerangs were fabricated from wood with a natural elbow. The wood grain followed the contour of the blades and often contained natural defects such as worm holes or small knots. Desirable characteristics in the materials include: stiffness, strength, ease in shaping, resistance to humidity, durability, low cost, and some flexibility. Material stiffness assures that the aerodynamic shape is maintained in wind conditions. Strength and durability are essential to fracture resistance and breakage due to impact. Materials that absorb moisture deform or warp the boomerang's shape. Flexibility allows the thrower to tune (bend) the boomerang for specific conditions. Some boomerang materials can be temperature sensitive making them more flexible during warm summer months and brittle during cold winter months.