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What is a Boomerang?
A boomerang is a curved and shaped piece of wood used by the Australian Aborigines as weapons and for hunting, boomerangs come in three types: returning, non-returning and those used in rituals.
The boomerang is made of hard wood and in Australia is always curved at an angle of between 90° and 120°. It is 60-90 cm long and weighs roughly 225 grams. The non-return boomerang is much longer, and from central Australia come specimens 180 cm long. One side of it is flat, the other convex, and along the convex side runs a sharp edge. The arms have a skew upon which the return or non-return of the boomerang depends.
A well-thrown nonreturning boomerang can wound a man at a distance of 500 feet (150 meters).
The returning boomerang, which has been widely copied as a toy, was developed by the Australian aborigines. It is made of a solid, lightweight piece of green wood that has been heated over a fire and bent into an angle or curve.
Returning boomerangs have arms of unequal length, with tips about 40 cm apart. Each arm is curved with an aerofoil section and is twisted so that the leading edge is slightly higher. It is this design which causes them to return when thrown.
Returning boomerangs were once shaped (usually from a suitably curved root) by heating the wood beside a fire and bending it when it was warm. This type of boomerang was often used in tests to determine which Aborigine could make his boomerang return closest to the place from where it was thrown. It was also used to trap birds by throwing it above a low-flying flock so that some birds swooped near the ground to avoid it and were snared in a net.
Returning boomerangs were made only in parts of eastern and south-eastern Australia and the far south-west of Western Australia.
A returning boomerang is usually 30cm to 75cm long, sharply bent or deeply curved with, often, one face flat and the other convex.
Its circling flight is caused by the contra-twist of the two halves. Returning boomerangs were used more for sport than for serious matters, but sometimes they were employed to scare birds into nets.
The returning boomerang possesses three salient features: (1) the arms have a hyperbolic curve; (2) one surface shows more curvature than the other; and (3) the arms are twisted relative to each other by an angle of 2° to 3°, thus resembling an airplane propeller. Best results with the returning type are achieved when it is grasped by one end and thrown overhand with a snap of the wrist at an angle of 60° to 75° from the horizontal.
The flight path of the returning boomerang is ovoid in plan, with the plane of flight rising from the thrower. Some skilled throwers are said to make the boomerang circle several times at the distant end of this loop before returning. The boomerang's initial spin diminishes throughout its flight, a spent boomerang hardly revolving in its final progress toward the thrower. Spin is sometimes augmented, it is alleged, by throwing the boomerang to strike the ground some yards in front of the thrower; after impact, it bounds into the air on its characteristic curving flight. In general, though, any impact during flight stops or deflects the weapon.
Returning boomerangs were not known, for example, to the Aborigines of SA and northwards, and indeed no boomerangs at all were made by some people from the Western Desert, nor by Aborigines from Cape York, Arnhem Land and the coastal Kimberleys. However, although a similar weapon has been known in certain other primitive societies, the returning boomerang is believed to be a purely Australian invention.
Wooden remains found at Wyrie SA, and reported in 1975, may have been been fragments of a returning boomerang. They were about 10,200 years old.
Despite popular belief, however, not all boomerangs come back, even when they leave the hands of an expert.
The non-returning boomerang, longer (up to 1 meter long) and heavier, and with a shallower curve, was thrown or used as a club for killing or maiming kangaroos, reptiles and ground birds. Or in fighting. The arms are angled and have sharp edges. Sometimes it was thrown so that it bounced along the ground, end over end. This boomerang could cause serious wounds to an enemy when thrown or used as a club.
Besides hunting and fighting, boomerangs were also used as digging-sticks, and as clapping sticks in corroborees and other ceremonies.
Ritual boomerangs are decorated with sacred symbols and vary in shape and size.
How to Throw a Boomerang
The boomerang is a flattened, angled form of throwing stick possessing certain aerodynamic properties that may give it a characteristic flight.
The boomerang, when about to be thrown, is held vertically. The thrower hurls the boomerang with a stiff-armed overhand throw and a flick of the wrist to make it spin so as much rotation as possible should be imparted to it. After travelling 45 m or more, revolving in an upright direction, it turns over on the flat side, curves away to the left, and begins to rise in the air, before it finally returns to the thrower and drops. It may be made to describe three or four circles, rising 45 m, before it returns to him, and it has been known to return to the thrower even after striking the ground.
This erratic flight pattern catches birds unaware. If the boomerang misses its target, it circles and returns toward the thrower, who may catch it and throw it again.
The war boomerang is of the non-return type and is thrown under the shield in a stooping position. It is sometimes made to strike the ground some 20 m ahead of the thrower, and then flies 70 meters or so further at a height of 1 to 2 meters.
In modern competitive sport the boomerang has been recognised as offering sportsmen two challenges. The first is to throw it on its teardrop-shaped flight path so that at the apex of its curve it is furthest from the thrower. The record for this challenge is held by Manuel Schütz who winged his boomerang on a huge arc which measured 238 meters at its furthest point.
The second challenge is to throw the boomerang so that it returns closest to the point from which it was thrown. Yoshi Kimura set an unbeatable record for accuracy when his boomerang returned to land at the exact spot from which he had thrown it.
The Boomerang Association of Australia was officially recognised in 1978 by the Confederation of Australian Sport. It holds official boomerang competitions, including an annual national championship.