Boomerangs

A boomerang is a tool, typically constructed as a flat air foil that, when thrown, is designed to spin about an axis perpendicular to the direction of its flight. A returning boomerang is designed to return to the thrower. It is well known as a weapon used by Indigenous Australians for hunting.

Boomerangs have been historically used for hunting, as well as a sport, and entertainment. They are commonly thought of as an Australian icon, and come in various shapes and sizes.

A boomerang is traditionally a long wooden device, although historically boomerang-like devices have also been made from bones. Modern boomerangs used for sport are often made from thin aircraft plywood, plastics such as ABS, polypropylene, phenolic paper, or even high-tech materials such as carbon fibre-reinforced plastics. Boomerangs come in many shapes and sizes depending on their geographic or tribal origins and intended function. Many people think of a boomerang as the Australian type, although today there are many types of more easily usable boomerangs, such as the cross-stick, the pinwheel, the tumblestick, the boomabird and many other less common types.

An important distinction should be made between returning boomerangs and non-returning boomerangs. Returning boomerangs fly and are examples of the earliest heavier-than-air man-made flight. A returning boomerang has two or more airfoil wings arranged so that the spinning creates unbalanced aerodynamic forces that curve its path so that it travels in an elliptical path and returns to its point of origin when thrown correctly. While a throwing stick can also be shaped overall like a returning boomerang, it is designed to travel as straight as possible so that it can be aimed and thrown with great force to bring down game. Its surfaces therefore are symmetrical and not uneven like the aerofoils which give the returning boomerang its characteristic curved flight.

The most recognisable type of the boomerang is the returning boomerang; while non-returning boomerangs, throwing sticks (or shaunies) were used as weapons, returning boomerangs have been used primarily for leisure or recreation. Returning boomerangs were also used to decoy birds of prey, thrown above long grass to frighten game birds into flight and into waiting nets. Modern returning boomerangs can be of various shapes or sizes as can be seen in a photo in the Modern use section.

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Wikipedia