boomerang
The boomerang ( plural -e or -s ) is a traditional throwing weapon of the Australian Aborigines. In modern times it is mainly used as a piece of sports equipment . Boomerangs can be made of wood, bone, metal, or plastic. While sports boomerangs return to the thrower if thrown correctly, this was not necessarily the case with the traditional Australian boomerang (" Kylie "). The advantage of the hunting boomerang is that it flies further, more straightforwardly and therefore more accurately than a returning boomerang.
description
Boomeranges are made from naturally grown hardwood , plywood , plastic or other solid materials. In the well-known traditional form, a boomerang looks like an "L" with two arms of roughly the same length. However, competition boomerangs often have three or more arms that do not need to be symmetrically arranged. In either case, the arms have a profile that creates dynamic lift .
Prehistoric boomerang finds
Rock carvings
Boomerang carvings are known from Norway and Sweden, but also from Africa, America, Asia and Australia.
The oldest known boomerang was discovered in 1985 in the Oblazowa Cave in the Polish Carpathian Mountains and was determined to be around 23,000 years old BP using radiocarbon dating . It was made from the tusk of a woolly mammoth and comes from the settlement layers of Gravettia . The weight of the original is 800 grams, which is considerably more than a wooden boomerang of the same size, the shape of which was used by Aborigines . Throwing tests with a replica of the same weight made of plastic showed very good throwing properties.
The oldest wooden boomerangs were unearthed at Wyrie Swamp in South Australia in 1973. They are around 10,000 years old.
In the shores of the Gelben Lake , an old arm of the Elbe in Magdeburg -Neustadt, an only slightly damaged boomerang was recovered from gravel in 1990. It is a "recurring specimen" made of ash wood . The device is 7-10 mm thick and has an angle of 110 °. The arm obtained is 22 cm long. An age determination by means of radiocarbon dating showed that the boomerang was between 800 and 400 BC. BC (Older Iron Age ) was carved. In addition to the German find, there is a boomerang from Velsen (Netherlands) found in 1962 , which dates back to 300 BC. BC (Younger Iron Age) and was stored in Gyttjaschlamm . At 60 °, this is angled much more flat than the Magdeburg find.
Whether Nordic rock art from the Neolithic and Bronze Age show shamans with boomerangs in some cases ( Notön island and Brådön in Sweden) cannot be decided in view of the inaccuracy of the images. On a rock painting on a cliff in the Ångermanälven river (Sweden), the rowers of an ancestral ship are shown in a typically abstract form, above whom curved lines (possibly boomerangs) float. On a Bronze Age rock carving in the province of Viken (Norway), a man carries a magical pair of boomerangs, which are clearly different in their execution from the paddles of the other boat occupants.
Throwing sticks were discovered in an Egyptian burial chamber , which are believed to be returning boomerangs. Egyptian depictions from the time of the New Kingdom show noble Egyptians who hunted waterfowl in the reed thicket with throwing sticks.
The boomerang in ethnography
Today it is primarily the Aborigines , the indigenous people of Australia, who are known for the use of boomerangs in their millennia-old history and up to the present day.
But hunting boomerangs have also been found in Africa, America and Asia (India).
Even with some Indian tribes in North America, boomerangs are still used as a weapon for hunting, so that it is now assumed that this throwing device has been around the world for a very long time.
development
The boomerang was originally developed as a hunting weapon and was usually heavier and larger than today's game or sports boomerangs. According to Hanns Peter's scientific research, there were 11 types of Australian boomerangs. Of these, 95% were not suitable for the return flight, but hunting devices that reached their target in a straight flight. Boomerangs were also used as a digging stick , musical instrument or percussion weapon by the Australian natives . Individual types of boomerangs could weigh up to 2 kg and be 1.30 m long.
James Cook brought the first Australian boomerang back from his trip to Europe in 1770.
The boomerang was discovered as a piece of sports equipment in the 1930s. There are now boomerang clubs all over the world. World championships are held in even years and European championships in odd years. Experienced throwers can throw replicas of hunting boomerangs up to 100 m.
Sports
Returning boomerangs have been used in Australia to hunt birds that fly in flocks. As sports and play equipment, they have always been used by the young Aborigines to practice handling this device.
Today's sports boomerangs have very different flight characteristics depending on their shape and profile and are used in competitions in corresponding disciplines.
Some fly a long time before returning to the launcher. Others come back very carefully and are used for trick catching or juggling. Still others come back after about three seconds, which makes them suitable for "fast catching". Another discipline is the "Australian Round", in which the throwing distance and return accuracy are assessed at the same time.
Disciplines
Today the following disciplines are usually carried out at tournaments: The following applies to all disciplines except long-distance throwing: The boomerang must cross at least the 20 m circle. Throwing takes place in a field that consists of several concentric circles.
- Australian Round (Aussie Round): The so-called supreme discipline. The boomerang should fly over the 50 m circle if possible and ideally be caught again in the center circle. Each thrower throws five times, for which points are awarded depending on the distance, return accuracy and catch.
- Accuracy: The thrower may no longer touch the boomerang after it has been released. Points are awarded based on how close to the center the boomerang lands. Each thrower throws five times.
- Endurance: The catches are counted for five minutes.
- Fast Catch: The time is stopped for five catches.
- Trick Catch / Doubling: Artificial catches such as catches behind the back or with the feet are required. In the doubling part, two boomerangs are thrown at the same time and both are caught one after the other with a special grip.
- MTA 100 (Maximal Time Aloft, 100 m field): The time that a boomerang spends in the air from being released to being caught is measured. The field usually consists of a circle with a diameter of 100 m; there is also a version without field restrictions (MTA unlimited).
- Long Distance: The boomerang is thrown from the middle of a 40 m wide baseline. The furthest distance the boomerang had from this baseline in the course of its flight path is measured. On the return flight, the baseline must be crossed again, but the boomerang must not be caught.
- Consecutive Catch: The catches are counted until a boomerang is dropped for the first time. Time doesn't matter.
- Juggling: Same as Consecutive Catch, but there are two boomerangs in play, with at least one in the air.
- Targeting: When targeting with hunting boomerangs, the hits and the proximity of the landing to a target object, e.g. B. Traffic cone.
However, there are many other, less common disciplines, some of which are only practiced for fun and are not competitive.
distribution
The boomerang sport is mainly practiced in Europe, North America, Japan, Australia and South America. The leading nations are Brazil (World Champion 2016), Germany, France, Switzerland, the United States, Japan and Australia. Depending on the country, there are also regional boomerang clubs in addition to the national organizations. The regional and national clubs hold demonstrations and workshops to promote the boomerang sport.
Current world records
(As of June 2010)
| discipline | result | Surname | country | year | competition |
|---|---|---|---|---|---|
| Accuracy 50 | 68 points | Thomas Stehrenberger | CHE | 2001 | Lausanne (CHE) |
| Accuracy 100 | 99 points | Alexander Opri | DEU | 2007 | Viareggio (ITA) |
| Aussie Round | 99 points | Fridolin Frost | DEU | 2007 | Viareggio (ITA) |
| Endurance | 81 catches | Manuel Schütz | CHE | 2005 | Milan (ITA) |
| Almost catch | 14.07 s | Manuel Schütz | CHE | 2017 | Besançon (FRA) |
| Trick Catch / Doubling | 533 points | Manuel Schütz | CHE | 2009 | Bordeaux (FRA) |
| Consecutive catch | 2251 catches | Haruki Taketomi | JPN | 2009 | nk (JPN) |
| MTA 100 | 139.1 s | Nick Citoli | United States | 2010 | Rome (ITA) |
| MTA unlimited | 380.59 s | Billy Brazelton | United States | 2010 | Rome (ITA) |
| Long distance | 238 m | Manuel Schütz | CHE | 1999 | Kloten (CHE) |
Guinness Book World Record
A boomerang was used to set the current Guinness World Record for the furthest muscle thrown object. David Schummy cast a distance of 427.2 meters on March 15, 2005 at the Murrarie Recreation Ground in Australia.
aerodynamics
The rotation of the boomerang acts like the rotation of a top. It keeps the alignment of the axis of rotation stable, even in the event of small disturbances. The rotation also creates a lift force on the wings of the boomerang. The strength of the lift depends on the speed of the air flowing around it.
As a result of the rotation, the wing moving in the direction of flight always gets more lift, since there the flow speed of the air results from the rotation speed plus the flight speed, while the rotation speed of the wing moving in the opposite direction is subtracted from the flight speed. This effect can also be found in the main rotor of a helicopter. There, this undesirable effect is corrected by the cyclical blade adjustment, in which the rotor blades moving in the direction of flight have a lower angle of attack than the declining ones.
The sum of all the buoyancy forces acting on the flying boomerang results in a force that wants to tilt the (virtual) axis of the rotating boomerang in such a way that the boomerang would fly straight ahead and rotate around a virtual axis in the direction of flight. So with a boomerang thrown right-handed, the leading wing would tip to the left at the highest point. The fact that this is not the case is based on another gyroscopic law , which states that a force that acts on the axis of a gyroscope does not lead to a deviation of the axis until it is offset by 90 ° in the direction of rotation. So the leading wing does not tilt at the highest point, but 90 ° later at the foremost point to the left, which forces the boomerang to turn.
A boomerang is thrown at a slight angle in order to compensate for gravity through effective buoyancy.
The orientation of the wing profile and the angle of attack determine the direction of rotation that the boomerang must be given when it is released. That is why there are mirror-image boomerangs for right and left-handers.
Colloquial language
Boomerang effect
A “boomerang effect” is used when a measure initially appears to be successful, but this success is wiped out again after a while or even turns into the opposite. In economics and medicine this process is called the rebound effect , in psychology it is called reactance .
Political boomerang
A “political boomerang” is a strategy which, instead of triggering the intended effect, has the opposite effect for various reasons and is directed against the author of the strategy: it falls back on him.
literature
- Philip Jones: Boomerang. Behind an Australian Icon. 1996, Kent Town, SA, Wakefield Press.
- Gerhard Schlatter: "Boomerang and Schwirrholz." 1985, Berlin, Reimer. ISBN 3-496-00830-X .
- Hanns Peter: The nature and meaning of the boomerang. 1986, Vienna, Braunmüller.
- Beat Aepli: Boomerang. Building blocks for working with 52 construction plans. 1987, SVHS, Liestal.
- Dietrich Evers: Boomerangs around the world. 2004, ISBN 3-937517-02-2 .
- Felix Hess: Boomerangs, Aerodynamics and Motion . Dissertation 1975, Rijksuniversiteit te Groningen.
Web links
- The history of the development of the boomerang
- Hunting boomerangs website
- physical explanation in English
Individual evidence
- ^ Paweł Valde-Nowak , Adam Nadachowski, Mieczyslaw Wolsan: Upper Palaeolithic boomerang made of a mammoth tusk in south Poland. Nature 329, 1987, pp. 436-438.
- ^ Paweł Valde-Nowak, The boomerang from Obłazowa and its prehistoric context. Anthropologie et Préhistoire 111, 2000. pp. 88-94.
- ↑ Dietrich Evers, Paweł Valde-Nowak: Throwing attempts with the Upper Palaeolithic throwing device from the Obłazowa Cave in the Polish Carpathians. Archäologisches Korrespondenzblatt 24, 1994, pp. 137-144
- ↑ Fact sheet Queensland Museum
- ↑ Dietrich Evers: Boomerang find in the Elbeschottern of Magdeburg-Neustadt and its testing . Archeology in Saxony-Anhalt 4, 1994, pp. 8-12.
- ^ HJ Calkoen: De eerste boemerang van Nederlandse bodem? Westerheem XI.
- ↑ Nämforsen rock art park in Näsåker
- ↑ D. Evers: Rock paintings of arctic hunter cultures of Stone Age Scandinavia. Stuttgart 1988 (F. Steiner Verlag).
- ^ Ian Wilson, Lost World of the Kimberley: Extraordinary New Glimpses of Australia's Ice Age Ancestors. Allen & Unwin, 2006. ISBN 1-74114-391-8
- ↑ Hanns Peter (1986): Nature and meaning of the boomerang. Vienna: Braunmüller
- ↑ Boomerang Association of Australia, overview of the boomerang records (accessed January 30, 2010)
- ↑ Majority rejects Koch's election campaign strategy. In: Spiegel online. January 6, 2008, accessed November 2, 2008 .