A boomerang is a simple wooden implement used for various purposes. Wood is hard fibrous lignified structural tissue produced as secondary Xylem in the stems of Woody plants notably trees but also shrubs It is primarily associated with Australian Aborigines, but other forms are found amongst peoples of North East Africa, Sardinia, Arizona and southern California Native Americans and in India. This is an article about a class of people as identified and defined within Australian law The Horn of Africa (alternatively Northeast Africa, and sometimes Somali Peninsula; shortened to HOA) is a Peninsula in East Africa Sardinia (sɑrˈdɪnɪə Sardegna Sardigna or Sardinnya is the second-largest island in the Mediterranean Sea (after Sicily) The State of Arizona ( is a state located in the southwestern region of the United States. India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country Besides the ancient boomerangs of Egypt and Sardinia, another old one found so far was discovered in a cave in the Carpathian Mountains in Poland and is believed to be about 20,000 years old. This article is about the country of Egypt For a topic outline on this subject see List of basic Egypt topics. Sardinia (sɑrˈdɪnɪə Sardegna Sardigna or Sardinnya is the second-largest island in the Mediterranean Sea (after Sicily) The Carpathian Mountains or Carpathians (Carpaţi Czech, Polish and Slovak: Karpaty; Ukrainian: Карпати Poland (Polska officially the Republic of Poland ^[1] Boomerangs come in many shapes and sizes depending on their geographic/tribal origins and intended function. The most recognizable type is the returning boomerang, a kind of throwing stick that, when thrown correctly, travels in a curved path and returns to its point of origin. The throwing stick is one of the first Weapons used by early humans and cultures all around the world Other types of boomerang are of the non-returning sort, and indeed, some are not thrown at all but are used in hand-to-hand combat by Aboriginal people. ^[2] Boomerangs can be variously used as hunting weapons, percussive musical instruments, battle clubs, fire-starters, decoys for hunting waterfowl, and as recreational play toys. The smallest boomerang may be less than 10 cm from tip-to-tip, and the largest over 2 meters in length. Tribal boomerangs may be inscribed and/or painted with designs meaningful to its maker. Most boomerangs seen today are of the tourist or competition sort, and are almost invariably of the returning type.

Contents 1 History 2 Hunting 3 Communication 4 Design 5 Throwing technique 6 Competitions and records 6.1 Competition disciplines 6.2 World records 7 Long distance boomerangs (LD) 7.1 General properties of long distance boomerangs 7.2 The flight path of long distance boomerangs 7.3 The historical evolution of interest in the discipline of long distance throwing 8 Related terms 9 See also 10 References 11 External links

History

Boomerang-like devices, including hunting sticks, have been used all over the world for hunting, religious and recreational activities. Hunting is the practice of pursuing Animals for Food, Recreation, or Trade. A religion is a set of Tenets and practices often centered upon specific Supernatural and moral claims about Reality, the Cosmos Recreation or fun is the expenditure of time in a manner designed for therapeutic refreshment of one's Body or Mind. Their origin is still not fully clear. Research has shown that ancient tribes in Europe used special throwing axes. Also, in ancient Egypt a special type of stick was exclusively used by the pharaohs for hunting birds. This article is about the country of Egypt For a topic outline on this subject see List of basic Egypt topics. Pharaoh is the title given in modern parlance to the ancient Egyptian kings of all periods However, the world famous "country of the boomerang" is Australia, where the Australian Aborigines have used both boomerangs and hunting sticks for many thousands of years. For a topic outline on this subject see List of basic Australia topics. Indigenous Australians are descendants of the first known human inhabitants of the Australian continent and its nearby islands. The name of the boomerang comes from the Indigenous Australian Turuwal tribe of Aborigines who lived south of Sydney, Australia^[3]. Indigenous Australians are descendants of the first known human inhabitants of the Australian continent and its nearby islands. The Turuwal people were an Aboriginal sub-group of the Dharuk language nation based in New South Wales, Australia. Indigenous Australians are descendants of the first known human inhabitants of the Australian continent and its nearby islands. Sydney (ˈsɪdniː is the most populous city in Australia, with a Metropolitan area population of approximately 4 For a topic outline on this subject see List of basic Australia topics. They were also mistakenly referred to as a woomerang, in confusion with the woomera throwing-sticks.

Today, boomerangs are most used as sporting items. There are different types of throwing contests: accuracy of return; aussie round; trick catch; maximum time aloft; fast catch; and endurance (See below). Maximum Time Aloft (MTA is a type of Boomerang competition involving specially engineered boomerangs The modern sport boomerang (often referred to as a 'boom' or 'rang'), is made of Finnish birch plywood, hardwood, plastic or composite materials and comes in many different shapes and colors. Finland, officially the Republic of Finland ( is a Nordic country situated in the Fennoscandian region of northern Europe. Plywood is a type of Engineered board made from thin sheets of Wood, called plies or veneers The term hardwood is used to describe Wood from broad-leaved angiosperm Trees mostly Deciduous, but not necessarily in the case of tropical Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products Composite materials (or composites for short are engineered Materials made from two or more constituent materials with significantly different physical or chemical Most sport boomerangs typically weigh less than 100 grams, with MTA boomerangs (boomerangs used for the maximum time aloft event) often under 25 grams. For other uses of the words gram or gramme see Gram (disambiguation.

In 2008, Japanese astronaut Takao Doi verified that boomerangs function in outer space as they do on Earth. For a topic outline on this subject see List of basic Japan topics. An astronaut or cosmonaut (космона́вт) is a person trained Takao Doi (土井隆雄 Doi Takao, born September 18, 1954) is a Japanese Astronaut and a veteran of two NASA Space Outer space, often simply called space, comprises the relatively empty regions of the Universe outside the escape velocities of Celestial bodies. ^[4][5] He repeated the same experiment that German Astronaut Ulf Meerbold did aboard Spacelab in 1992 and French Astronaut Jean-François Clervoy aboard MIR in 1997. ^[6]

Hunting

It is believed that the shape and elliptical flight path of the returning boomerang makes it useful for hunting. Noise generated by the movement of the boomerang through the air, and, by a skilled thrower, lightly clipping leaves of a tree whose branches house birds, would help scare the birds towards the thrower. This was used to frighten flocks or groups of birds into nets that were usually strung up between trees or thrown by hidden hunters. ^[7]

Boomerangs for hunting larger prey, such as kangaroo, were used for small prey as well. A kangaroo is a Marsupial from the family Macropodidae (macropods meaning 'large foot' These boomerangs are modified as such to fly in a straight path when thrown horizontally and are heavy enough to take down a kangaroo on impact to the legs or knees. For hunting emu, the boomerang is thrown toward the neck, breaking it. The Emu ( Dromaius novaehollandiae, is the largest Bird native to Australia and the only extant member of the Genus

Communication

It has been documented that Western Victorian "aboriginals" used the returnable boomerang, in addition to hunting, as a means of communication over long distances. This visual communication is especially useful when winds or distance make impossible other well known methods of communication such as "koo-eee".

Design

A boomerang is an airfoil. An airfoil (in American English) or aerofoil (in British English) is the shape of a Wing or blade (of a Propeller, rotor Though it is not a requirement that the boomerang be in its traditional shape, it is usually flat. A falling boomerang starts spinning and most then fall in a spiral. When the boomerang is thrown with high spin, the wings produce lift. WING "ESPN 1410" is a commercial AM radio station in Dayton Ohio operating with 5000 watts at 1410 kHz with studios offices and transmitter located on David In the context of a Fluid flow relative to a body the lift force is the component of the Aerodynamic force that is Perpendicular to the flow Larger boomerangs are used in hunting, thus they drop on the ground after striking the target. Smaller ones are used in sport, and are the only boomerangs that return to the thrower. Because of its rapid spinning, a boomerang flies in a curve rather than a straight line. When thrown correctly a boomerang returns to its starting point.

Returning boomerangs consist of two or more arms or wings, connected at an angle. WING "ESPN 1410" is a commercial AM radio station in Dayton Ohio operating with 5000 watts at 1410 kHz with studios offices and transmitter located on David Each wing is shaped as an airfoil, air travels faster over one surface of an airfoil than the other, as the air is accelerated due to the curvature, thus creating lift, along what is roughly a plane which intersects the airfoil at a near right angle along the long axis of the wing. An airfoil (in American English) or aerofoil (in British English) is the shape of a Wing or blade (of a Propeller, rotor In the context of a Fluid flow relative to a body the lift force is the component of the Aerodynamic force that is Perpendicular to the flow

These wings are set so that the lift created by each wing opposes the lift of the other, but at an angle such that the flight pattern is constantly shifted as the forces of lift, drag, speed, rotational inertia etc. This article is about the moment of inertia of a rotating object. 'attempt' to reach equilibrium, see Boomerang engineer.

This is what makes the boomerang return to the thrower when thrown correctly. This is also what makes the boomerang fly straight up into the air when thrown incorrectly. With the exception of long-distance boomerangs, they should not be thrown sidearm or like a Frisbee, but rather throw with the long axis of the wings rotating in an almost-vertical plane. When throwing a returning boomerang correctly it is important to follow the correct insturctions to achieve a successful return.

Some boomerangs have turbulators - bumps or pits on the top surface that act to make the flight more reliable. A turbulator is a device for improving the flow of air over a wing ^[8]

Fast Catch boomerangs usually have three or more symmetrical wings (in the planform view), whereas a Long Distance boomerang is most often shaped similar to a question mark. A planform or Plan view is a vertical Orthographic projection of an object on a horizontal plane like a Map. ^[9] Maximum Time Aloft boomerangs mostly have one wing considerably longer than the other. This feature, along with carefully executed bends and twists in the wings, help to set up an 'auto-rotation' effect to maximize the boomerang's hover-time in descending from its highest point in the flight.

Throwing technique

A left-handed boomerang circles towards the right, and a right-handed boomerang circles towards the left. Most sport boomerangs are in the range of about 2. 5 to 4 ounces. This article is about the unit of mass For the unit of force see Pound-force. The range on most of these is between 25 and 40 yards/metres. A right- or left-handed boomerang can be thrown with either hand, but the flight direction will depend upon the boomerang, not the thrower. Throwing a boomerang with the wrong hand requires a throwing motion that many throwers may find awkward. The wings of the boomerang should be at a 15 degree angle. The other way also works, but many people find it easier to learn this way. The boomerang should be held by the tip using the thumb and one, two or three fingers, and then launched forward quickly while trying more for force than for very much spin. It should flatten out midflight and arc around, sometimes coming to rest a little in front of the thrower or behind the thrower, but ideally it should hover gently and allow the thrower to catch it as a sort of sandwich between the thrower's hands. Returning boomerangs shouldn't be thrown level like a flying disc, as it will turn in the direction of the top of its airfoils, so if that direction happens to be up rather than to the side it may fly high enough that the landing causes damage to the boomerang or whatever it lands on.

Wind speed and direction are very important for a successful throw. A right-handed boomerang is thrown to the right of the wind. Angle to the wind depends on the boomerang, but starting with a 45 degree angle is recommended. Depending on where the boomerang lands, this angle can be modified so that a closer return is achieved. For example, if the boomerang lands too far on the left, throw more to the right of the wind the next time. As for the wind speed, a light wind is ideal. If the wind is strong enough to fly a kite, that's usually too strong for boomerangs.

Competitions and records

In international competition, a world cup is held every second year, with teams from Germany and the United States dominating international competition. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. The United States of America —commonly referred to as the The individual World Champion title was won in 2000, 2002 and 2004 by Swiss thrower Manuel Schütz. In 2006, Fridolin Frost from Germany won the title, with Manuel Schütz finishing third.

Competition disciplines

Modern boomerang tournaments usually involve some or all of the events listed below ^[10] In all disciplines the boomerang must travel at least 20 meters from the thrower. Throwing takes place individually. The thrower stands at the centre of concentric rings marked on an open field.

• Aussie Round: considered by many to be the ultimate test of boomeranging skills. The boomerang should ideally cross the 50 meter circle and come right back to the centre. Each thrower has five attempts. Points are awarded for distance, accuracy and the catch.
• Accuracy: points are awarded according to how close the boomerang lands to the centre of the rings. The thrower must not touch the boomerang after it has been thrown. Each thrower has five attempts. In major competitions there are two accuracy disciplines: Accuracy 100 and Accuracy 50
• Endurance: points are awarded for the number of catches achieved in 5 minutes.
• Fast Catch: the time taken to throw and catch the boomerang five times. The winner has the fastest timed catches.
• Trick Catch/Doubling: points are awarded for trick catches behind the back, between the feet, etc. In Doubling the thrower has to throw two boomerangs at the same time and catch them in sequence in a special way.
• Consecutive Catch: points are awarded for the number of catches achieved before the boomerang is dropped. The event is not timed.
• MTA 100 (Maximal Time Aloft, field size: 100 metres): points are awarded for the length of time spent by the boomerang in the air. The field is normally a circle measuring 100 metres. An alternative to this discipline, without the 100 metre restriction is called MTA unlimited.
• Long Distance: the boomerang is thrown from the middle point of a 40 metre baseline. The furthest distance travelled by the boomerang away from the baseline is measured. On returning the boomerang must cross the baseline again but does not have to be caught. A special section is dedicated to LD below.
• Juggling: as with Consecutive Catch, only with two boomerangs. At any given time one boomerang must be in the air.

There are many other boomerang disciplines, many played just for fun, but most of these are not considered official competition events.

World records

(May 2008)

Discipline	Result	Name	Year	Tournament
Accuracy 100	99 points	Alex Opri (D)	2007	Viareggio (ITA)
Accuracy 50	68 points	Thomas Stehrenberger (CH)	2001	Lausanne (CH)
Aussie Round	99 points	Fridolin Frost (D)	2007	Viareggio (ITA)
Endurance	81 catches	Manuel Schütz (CH)	2005	Milano (I)
Fast Catch	14. 55 s	Parker Carlisle (USA)	2002	Emmaus (USA)
Trick Catch/Doubling	390 points	Manuel Schütz (CH)	2004	Milano (I)
Consecutive Catch	1297 catches	Manuel Schütz (CH)	2005	Aalen (D)
MTA 100	104. 87 s	Eric Darnell (USA)	1997	Portland (USA)
MTA unlimited	229. 82 s	Betsylew Miale-Gix (USA)	2008	Tucson (USA)
Long Distance	238 m	Manuel Schütz (CH)	1999	Kloten (CH)

Non-discipline record: Smallest Boomerang: Sadir Kattan of Australia in 1997 with 48 mm [1. 8 in] long and 45 mm [1. 77 in] wide. This tiny boomerang flew the required 20 metres, returning to the accuracy circles on 22 March 1997 at the Australian National Championships. [2]

Long distance boomerangs (LD)

Long distance boomerang throwers aim to have the boomerang go the furthest possible while returning not too far from the throwing point. In competition the boomerang must intersect an imaginary surface defined as an infinite vertical extrude of a 40 m large line centred on the thrower. In practice, the definition is not so strict and the thrower is happy whenever he does not have to travel 50 m after each throw to recover the boomerang. This is often not true, though.

General properties of long distance boomerangs

Long distance boomerangs are optimized to have minimal drag while still having enough lift to fly and return. For this reason they have a very narrow throwing window which discourages many beginners from continuing with this discipline. For the same reason, the quality of manufactured long distance boomerangs is often non-deterministic.

The flight path of long distance boomerangs

The projection of the flight path of long distance boomerang on the ground resembles a water drop. For older types of long distance boomerangs, the first and last third of the flight path were very low while the middle third was a fast climbing flowed by a fast descent. Nowadays boomerangs are made in a way that their whole flight path is almost planar with a constant climbing during the first half of the trajectory and then a rather constant descent during the second half.

From theoretical point of view, long distance boomerangs are interesting also for the following reason: for achieving a different behaviour during different flight phases, the ratio of the rotation frequency to the forward velocity has a U shaped function, i. e. its derivate crosses 0. Practically it means that the boomerang being at the furthest point has a forward velocity very low. The kinetic energy of the forward component is then stored in the potential energy. This is not true for other types of boomerangs where the loss of kinetic energy is non-reversible.

The historical evolution of interest in the discipline of long distance throwing

Long distance boomerang throwing had been considered as the royal competition in the 20th century but with new materials and approach that coincides with the 21st century, throwing 100 m became normal and the interest in this category declined. Following reasons explain the evolution:

• Throwing technique: The throwing technique is slightly different and less natural as the boomerang must be thrown almost horizontally lied down but aiming high yet with maximal power used.
• Deceiving exercising: Long distance boomerangs are more difficult to make or to acquire because they must be much more optimized to achieve good performance which requires more workload. On the other hand they are easy to lose because at 100 m only individuals with good vision still see them clearly and sometimes they do not even make the turn and continue straight forward. It also matters that not all fields are big enough, flat and empty to allow exercising.
• Put apart in tournaments: Due to difficulties to organize competition in this category the events are often separated from the rest of disciplines and scheduled as the last day of the whole tournament, often a Monday.

On the other hand the long distance throwers being very few compared to other disciplines still benefit from a family like spirit present on all LD events.

Related terms

Kylie is one of the Aboriginal words for the hunting stick used in warfare and for hunting animals. ^[11] Instead of following a curved flight path, it flies in a straight line from the thrower. They are typically much larger than boomerangs. It can travel very long distances, and due to its size and hook shape can cripple or kill an animal or human opponent. The word is perhaps an English corruption of a word meaning boomerang taken from one of the Western Desert languages, for example, the Warlpiri word karli. The Warlpiri are a group of Indigenous Australians, many of whom speak the Warlpiri language.

See also

• Batarang
• Roomarang
• Throwing Stick

References

External links

• International Federation of Boomerang Associations (IFBA)
• Boomerang Association of Australia (BAA)
• Canadian Boomerang Throwers Association (Canboom)
• United States Boomerang Association: Information, Events and more (USBA)
• Danish Boomerang Club
• History of Boomerangs
• Boomerang History
• Unspinning the Boomerang, The Maths and Physics of a Boomerang
• Boomerang aerodynamics, An online dissertation.
• Illustrated How to guide for crafting a boomerang
• Explanation where the word Boomerang may come from
• Boomerang Competition Events
• Boomerang Passion, a French boomerang portal (in English)
• How to Throw Boomerangs, a beginner's to advanced guide to throwing boomerangs.
• BAGGRESSiVE, the reference site for long distance boomerang (LD)
• Discussion Group for people who throw, design, and build Boomerangs.

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