Archery is the art, practice, or skill of propelling arrows with the use of a bow (bow and arrow), from Latin arcus. Archery has historically been used for hunting and combat; in modern times, however, its main use is that of a recreational activity. One who practices archery is typically known as an "archer" or "bowman", and one who is fond of or an expert at archery can be referred to as a "toxophilite".[1]
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The bow seems to have been invented in the late Paleolithic or early Mesolithic periods. The oldest indication for its use in Europe comes from the Stellmoor in the Ahrensburg valley north of Hamburg, Germany and date from the late Paleolithic, about 10,000–9000 BC. The arrows were made of pine and consisted of a mainshaft and a 15–20 centimetre (6–8 inches) long fore shaft with a flint point. There are no definite earlier bows; previous pointed shafts are known, but may have been launched by atlatls rather than bows. The oldest bows known so far come from the Holmegård swamp in Denmark. Bows eventually replaced the atlatl as the predominant means for launching shafted projectiles, on every continent except Australia (woomera used), though the atlatl persisted alongside the bow in parts of the Americas, notably Mexico (from which its Nahuatl name comes) and amongst the Inuit.
Bows and arrows have been present in Egyptian culture since its predynastic origins. In the Levant, artifacts which may be arrow-shaft straighteners are known from the Natufian culture, (c. 12,800–10,300 BP (before present)) onwards. The Khiamian and PPN A shouldered Khiam-points may well be arrowheads.
Classical civilizations, notably the Assyrians, Persians, Somalis, Parthians, Indians, Koreans, Chinese, and Japanese and Turks fielded large numbers of archers in their armies. The Sanskrit term for archery, dhanurveda, came to refer to martial arts in general.
Archery was highly developed in Asia and in the Islamic world. In East Asia, ancient Korean civilizations, such as the Silla, Baekje, and Goguryeo were well known for their regiments of exceptionally skilled archers.[2] Central Asian tribesmen (after the domestication of the horse) and American Plains Indians (after gaining access to horses) were extremely adept at archery on horseback, with especially Mongol horsemen being renowned for fielding mounted archers in their armies. The lightly armoured, but highly mobile Mongol archers proved to be excellently suited to warfare in the Central Asian steppes, helping to conquer a large part of the known world at that time. In Europe, the English longbow proved its worth for the first time in Continental warfare at Crecy, France, in the year 1346.[3]
The development of firearms rendered bows obsolete in warfare. Despite the high social status, ongoing utility, and widespread pleasure of archery in Korea, England, China, Japan, Turkey, Armenia, America, Egypt, India and elsewhere, almost every culture that gained access to even early firearms used them widely, to the relative neglect of archery. Early firearms were vastly inferior in rate-of-fire, and were very susceptible to wet weather. However, they had longer effective range[2] and were tactically superior in the common situation of soldiers shooting at each other from behind obstructions. They also required significantly less training to use properly, in particular penetrating steel armour without any need to develop special musculature. Armies equipped with guns could thus provide superior firepower by sheer weight of numbers, and highly-trained archers became almost obsolete on the battlefield. However, archers are still effective and have seen action even in the 21st century.[4] Traditional archery remains in use for sport, and for hunting in many areas.
In the United States, competition archery and bowhunting for many years used English-style longbows. The revival of modern primitive archery may be traced to Ishi, who came out of hiding in California in 1911.[5] Ishi was the last of the Yahi Indian tribe.[6] His doctor, Saxton Pope, learned many of Ishi's archery skills, and passed them on.[7][8] The Pope and Young Club, founded in 1961 and named in honor of Pope and his friend, Arthur Young, is one of North America's leading bowhunting and conservation organizations. Founded as a nonprofit scientific organization, the Club is patterned after the prestigious Boone and Crockett Club. The Club advocates and encourages responsible bowhunting by promoting quality, fair chase hunting, and sound conservation practices.
From the 1920s, professional engineers took an interest in archery, previously the exclusive field of traditional craft experts.[9] They led the commercial development of new forms of bow including the modern recurve and compound bow. These modern forms are now dominant in modern Western archery; traditional bows are in a minority. In the 1980s, the skills of traditional archery were revived by American enthusiasts, and combined with the new scientific understanding. Much of this expertise is available in the Traditional Bowyer's Bibles (see Additional reading). Modern game archery owes much of its success to Fred Bear, an American bow hunter and bow manufacturer.[10]
At the end of the eighteenth century archery became popular amongst the English gentry thanks to a fashion for the gothic, curious and medieval. Encouraged by Royal patronage and, later, the popularity of the work of Sir Walter Scott, archery societies were set up across the country, each with its own strict entry criteria, outlandish costumes and extravagant balls. The clubs were "the drawing rooms of the great country houses placed outside" and thus came to play an important role in the social networks of local elites. As well as its emphasis on display and status, the sport was notable for its popularity with females. Young women could not only compete in the contests but retain and show off their "feminine forms" whilst doing so. Thus archery came to act as a forum for introductions, flirtation and romance.[11]
Deities and heroes in several mythologies are described as archers, including the Greek Artemis and Apollo, the Roman Diana and Cupid, the Germanic Agilaz, continuing in legends like those of William Tell, Palnetoke, or Robin Hood. Armenian Hayk and Babylonian Marduk, Indian Karna, Arjuna, Rama, Abhimanyu, and Shiva, and Persian Arash were all archers. Earlier Greek representations of Heracles normally depict him as an archer. The Nymphai Hyperboreioi (Νύμφαι Ὑπερβόρειοι) were worshipped on the Greek island of Delos as attendants of Artemis, presiding over aspects of archery; Hekaerge (Ἑκαέργη), represented distancing, Loxo (Λοξώ), trajectory, and Oupis (Οὖπις), aim.[12] In East Asia, Yi the archer features in several early Chinese myths,[13] and the historical character of Zhou Tong features in many fictional forms. Jumong, the first Taewang of the Goguryeo kingdom of the Three Kingdoms of Korea, is claimed by legend to have been a near-godlike archer. Archery features in the story of Oguz Khagan. In West African Yoruba belief, Osoosi is one of several deities of the hunt who are identified with bow and arrow iconography and other insignia associated with archery.
While there is great variety in the construction details of bows (both historic and modern) all bows consist of a string attached to elastic limbs that store mechanical energy imparted by the user drawing the string. Bows may be broadly split into two categories: those drawn by pulling the string directly and those that use a mechanism to pull the string.
Directly drawn bows may be further divided based upon differences in the method of limb construction, notable examples being self bows, laminated bows and composite bows. Bows can also be classified by the bow shape of the limbs when unstrung; in contrast to simple straight bows, a recurve bow has tips that curve away from the archer when the bow is unstrung. The cross-section of the limb also varies; the classic longbow is a tall bow with narrow limbs that are D-shaped in cross section, and the flatbow has flat wide limbs that are approximately rectangular in cross-section. The classic D-shape comes from the use of the wood of the yew tree. The sap-wood is best suited to the tension on the back of the bow, and the heart-wood to the compression on the belly. Hence, a limb sector of yew wood shows the narrow, light-coloured sap-wood on the 'straight' part of the D, and the red/orange heartwood forms the curved part of the D, to balance the mechanical tension/compression stress. Cable-backed bows use cords as the back of the bow; the draw weight of the bow can be adjusted by changing the tension of the cable. They were widespread among Inuit who lacked easy access to good bow wood. One variety of cable-backed bow is the Penobscot bow or Wabenaki bow, invented by Frank Loring (Chief Big Thunder) about 1900.[14] It consists of a small bow attached by cables on the back of a larger main bow.
A compound bow is a bow designed to reduce the force required to hold the string at full draw, hence allowing the archer more time to aim with less muscular stress. Most compound designs use cams or elliptical wheels on the ends of the limbs to achieve this. A typical let-off is anywhere from 65%–80%. For example, a 60-pound bow with 80% let-off will only require 12 pounds of force to hold at full draw. Up to 99% let-off is possible.[15] The compound bow has become the most widely used type of bow for all forms of hunting in North America. The compound bow has become a highly popular form of archery, so much so that it is the most commonly used bow form in the USA. The compound bow was invented by Holless Wilbur Allen in Missouri, and a US patent was filed in 1966 and granted in 1969.
Mechanically drawn bows typically have a stock or other mounting, such as the crossbow. They are not limited by the strength of a single archer and larger varieties have been used as siege engines.
The most common form of arrow consists of a shaft with an arrowhead attached to the front end and with fletchings and a nock attached to the other end. Arrows across time and history are normally carried in a container known as a quiver. Shafts of arrows are typically composed of solid wood, fiberglass, aluminium alloy, carbon fiber, or composite materials. Wooden arrows are prone to warping. Fiberglass arrows are brittle, but can be produced to uniform specifications easily. Aluminium shafts were a very popular high-performance choice in the latter half of the 20th century due to their straightness, lighter weight, and subsequently higher speed and flatter trajectories. Carbon fiber arrows became popular in the 1990s and are very light, flying even faster and flatter than aluminium arrows. Today, arrows made up of composite materials are the most popular tournament arrows at Olympic Events, especially the Easton X10 and A/C/E.
The arrowhead is the primary functional component of the arrow. Some arrows may simply use a sharpened tip of the solid shaft, but it is far more common for separate arrowheads to be made, usually from metal, stone, or other hard materials. The most commonly used forms are target points, field points, and broadheads, although there are also other types, such as bodkin, judo, and blunt heads.
Fletching is traditionally made from bird feathers. Also solid plastic vanes and thin sheetlike spin vanes are used. They are attached near the nock (rear) end of the arrow with thin double sided tape, glue, or, traditionally, sinew. Three fletches is the most common configuration in all cultures, though as many as six have been used. Two will result in unstable arrow flight. When three-fletched the fletches are equally spaced around the shaft with one placed such that it is perpendicular to the bow when nocked on the string (though with modern equipment, variations are seen especially when using the modern spin vanes). This fletch is called the "index fletch" or "cock feather" (also known as "the odd vane out" or "the nocking vane") and the others are sometimes called the "hen feathers". Commonly, the cock feather is of a different color. Traditionally, the hens are solid and the cock is barred. However, if archers are using fletching made of feather or similar material, they may use same color vanes, as different dyes can give varying stiffness to vanes, resulting in less precision. When four-fletched, often two opposing fletches are cock feathers and occasionally the fletches are not evenly spaced.
The fletching may be either parabolic (short feathers in a smooth parabolic curve) or shield (generally shaped like half of a narrow shield) cut and is often attached at an angle, known as helical fletching, to introduce a stabilizing spin to the arrow while in flight. Whether helicial or straight fletched, when natural fletching (bird feathers) are used it is critical that all feathers come from the same side of the bird. Oversized fletchings can be used to accentuate drag and thus limit the range of the arrow significantly; these arrows are called flu-flus. Misplacement of fletchings can often change the arrow's flight path dramatically.
Dacron and other modern materials offer high strength for their weight and are used on most modern bows. Linen and other traditional materials are still used on traditional bows. Almost any fiber can be made into a bow string. The author of "Arab Archery" suggests the hide of a young, emaciated camel.[16] Njál's saga describes the refusal of a wife, Hallgerður, to cut her hair in order to make an emergency bowstring for her husband, Gunnar Hámundarson, who is then killed.
Most archers wear a bracer (also known as an arm-guard) to protect the inside of the bow arm from being hit by the string and prevent clothing from catching the bow string. The bracer does not brace the arm; the word comes from the armoury term "brassard", meaning an armoured sleeve or badge. The Navajo people have developed highly-ornamented bracers as non-functional items of adornment.[17] Some archers (mostly women) also wear protection on their chests, called chestguards or plastrons. The Amazon myth is that they had one breast removed to solve this problem. Roger Ascham mentions one archer, presumably with an unusual shooting style, who wore a leather guard for his face.[18]
The drawing digits are normally protected by a leather tab, glove, or thumb ring. A simple tab of leather is commonly used, as is a skeleton glove. Medieval Europeans probably used a complete leather glove.[19]
Eurasiatic archers who used the thumb or Mongolian draw protected their thumbs, usually with leather according to the author of Arab Archery,[20] but also with special rings of various hard materials. Many surviving Turkish and Chinese examples are works of considerable art. Some are so highly ornamented that the users could not have used them to loose an arrow. Possibly these were items of personal adornment, and hence value, remaining extant whilst leather had virtually no intrinsic value and would also deteriorate with time. In traditional Japanese archery a special glove is used, provided with a ridge which is used to draw the string.[21]
Archers using compound bows most commonly use a release aid to hold the string and release it precisely, although finger tabs are also popular with compound bows, especially among older archers who have used finger tabs when shooting recurve bows. The release aid attaches to the bowstring just below the nocking point or at the D loop and permits the archer to release the string by the use of some form of trigger. When such a device was first invented (patent filed in USA, 1879) it was known as a "clutch".[22] The trigger may be an actual trigger lever which is depressed by a finger or thumb (positive), or held then released (negative) but there are numerous types. Hydraulic and mechanical time delay triggers have been used, as have "back tension" triggers which are operated by either a change in the position of the release or "true back tension"; that is to say the release triggers when a pre-determined draw weight is reached.
A mechanical release (the use of the word "aid" can be omitted when context is appropriate) permits a single point of contact on the string instead of three fingers as most commonly used with finger tabs. This allows less deformity in the string at full draw, as well as providing a more consistent release. This is primarily because the most successful types operate with positive pressure, whereas the conventional 'fingers' release is negative pressure. (Some archers prefer three fingers under the arrow with a finger tab, whereas the split-finger approach, having one finger above the arrow and two fingers below the arrow is the most commonly-used finger shooting method amongst English and modern North American archers who do not use mechanical release aids.)
The mechanical release holds the string by retaining it by some form of gate or loop of cord. The gate or cord is released by operation of the trigger, allowing the string to push open the gate or cord. Consequently, any sideways movement of the string, and hence arrow nock, is likely to be less than if fingers were used, although, if a consistent finger tab release is performed, the differences are often negligible in terms of practical hunting accuracy at ranges up to 30 yards.
In Central Asia and the Middle East, thumbrings were also used for string retention and release. The arrow must be positioned on the other side of the bow, (on the right hand side of the bow for a right-handed shooter) to properly use a thumbring, to allow the "archers's paradox" to work, since the thumb opens in the opposite direction to the fingers.[21]
The choice of a mechanical release aid vs. a finger tab must be accounted for in a compound bow's tuning and sighting, as well as choice of arrow rest, as finger-released arrows will group in a different spot when using a mechanical release aid versus a finger tab. Likewise, the choice of arrow rest for a compound bow depends on whether a finger release archery tab or mechanical release aid is used; for a finger-released arrow, a plunger pin is most commonly used as the arrow rest, to impart a tuned impulse laterally to the arrow at the moment of release to improve point-of-impact groupings. In contrast, for a release aid configuration, a Whisker-biscuit arrow rest is very commonly used with a compound bow.
This is a general term for various types of weights, usually on rods, mounted on the bow to increase stability i.e. lessen movement on release, thereby increasing accuracy. A typical assortment may be seen in the picture of a tournament in West Germany, at the head of this article. Note that if the shooting technique of the archer were perfect, then, with everything else remaining constant, no stabilisers would be required. It is the inconsistences of the archer that stabilisers can help to reduce. All bodies have inertia, and it is static inertia that bow-weights "use", which means that they resist movement. Consequently, on the application of any force on the bow, e.g. 1) muscular force, whether voluntary or involuntary: 2) the reaction of the bow to the acceleration of the bow limbs, string and arrow: 3) the further reaction of the bow as the string becomes taut and the arrow flies free: the actual physical movement of the bow centre section will be less with the addition of weights than it would have been without. Clearly, the forces acting on the centre section are potentially the same on any shot, and by increasing the static inertia, movement will be reduced. Accuracy comes from repeatability. The reduction of inadvertent movements enhances repeatability. The various types of stabilisers are each designed to minimise a particular direction of movement. It should be noted that these "movements" are those that may occur between the instant of true aim/string release, and the arrow flying free: not "follow-through" and similar activities, these merely indicate what went before. All weight added to the centre section will reduce trembling or shake during the aim, but energy to hold the bow against gravity will obviously increase. Also, the addition of weight will change the shooting characteristics and matching of the arrows to the bow. The successful addition of stabilisers can only be achieved by actual testing and accuracy grouping.[23]
Usually fitted into the centre section in line with the bow arm, or just below the hand position. The addition of this weight projects the centre of gravity (C of G) of the bow forwards, with the result that, firstly, "torque" effect (sideways twisting of the bow-hand) movement is reduced. Since, at full draw, the bow cannot twist, as the string is (in theory) preventing such action, the effect is only apparent on string release. Hence, the bow centre section turns to some degree on release, the arrow being directed to either the left or right.[24] But, with the forward C of G, the effect is reduced. Similarly, "topping" (upwards) or "heeling" (downwards) inconsistences of the bow-hand are reduced. Secondly, with actual movement of the bow-hand sideways, up, down, or any combination, because the C of G is in front of the hand, the bow will turn in the opposite direction, to correct, to some degree, the archer's error. Further, an effect that does not actually give enhanced accuracy, except in the mind of the archer, is the pleasing "forward roll" of the bow, as part of the follow-through, with a relaxed bow-hand and forward C of G.
Fitted above and below the bow-hand, normally close to where the limbs meet the centre section, these have similar effects to the single long-rod, but also have a third effect. Because of their positioning, the twin weights also resist rotation instigated by a bow-hand error. If this error were not reduced, left or right shots would occur, because the aiming of the arrow takes gravity into account to gauge the trajectory. Consequently, with perfect aim, if the bow rotates on release, the effect will be the same as not holding the bow vertically, i.e.left or right. Similarly to the long-rod, a "forward roll" will be induced on release and, in addition, because the twin stabilisers are positioned at the base of the limbs, depending on the rigidity of the mounts, some vibration may be damped, giving a smoother feel to the shot.
Fitted usually below the bow-hand on the centre section, because they point back towards the archer, they bring the C of G backwards. Consequently, they are typically used in conjunction with a long-rod stabiliser, the long-rod having sufficient turning moment to exceed the negative effect of the reverse weights, and so keep the forward roll of the bow on release, this being generally accepted as a desirable feature. Hence, the forward C of G effect will not be as great, but, because the reverse weight or weights are extended horizontally from the vertical centre section, their effect is to reduce vertical turning caused by bow-hand torque. This is, of course, in addition to any long-rod stabiliser anti-torque effect.
Consider the bow as being potentially on a pivot at the pressure point of the bow-hand. If the archer applies inadvertent pressure off centre of the pressure point, then inadvertent movement of the bow will result, with loss of accuracy. By careful study of the bow's movement, the appropriate positioning and addition of weight(s) may be tried, to reduce errors, although prevention is better than cure.
Further, various types of mount have been used, to allow some degree of flexure between the bow and the stabiliser weight. Similarly, the weight may be on an extension rod that may flex in itself. The object of the exercise should be kept in mind, and that object is to reduce bow inadvertent movement. Any flexure will allow some movement of the bow, without similar movement of the weight, hence lessening the weight inertia. However, many archers have found an apparent improvement in their accuracy with the use of flex / mounts. The weight in hand remains unchanged, and so may contribute to steadyness of aim. Also, the flexing gives a "rubbery" feeling, as though the bow wants to remain steady on aim. Consequently, it may be that such effect helps the archer's feeling of confidence on the shot, thereby contributing to accuracy.
The bow is held in the hand opposite to the archer's dominant eye, though holding the bow in the dominant hand side is advocated by some. This hand is referred to as the bow hand and its arm the bow arm. The opposite hand is called the drawing hand or string hand. Terms such as bow shoulder or string elbow follow the same convention. Right-eye-dominant archers hold the bow with their left hand, have their left side facing the target, sight towards the target with their right eye and handle the arrow and string with their right hand.
To shoot an arrow, an archer first assumes the correct stance. The body should be at or nearly perpendicular to the target and the shooting line, with the feet placed shoulder-width apart. As an archer progresses from beginner to a more advanced level an "open stance" is often developed. Each archer will have a particular preference but mostly this term indicates that the leg furthest from the shooting line will be a half to a whole foot-length from the other foot, on the ground.
To load, the bow is pointed toward the ground, tipped slightly clockwise of vertical (for a right handed shooter) and the shaft of the arrow is placed on the arrow rest or shelf. The back of the arrow is attached to the bowstring with the nock (a small locking groove located at the proximal end of the arrow). This step is called "nocking the arrow". Typical arrows with three vanes should be oriented such that a single vane, the "cock feather", is pointing away from the bow, or, on a compound bow, that this feather is pointed upwards so as for the arrow to clear the arrow rest without any fletchings touching the arrow rest or pin at the moment of release of the arrow.
The bowstring and arrow are held with three fingers, or with a mechanical arrow release. Most commonly, for finger shooters, the index finger is placed above the arrow and the next two fingers below, although several other techniques have their adherents around the world, involving three fingers below the arrow, or an arrow pinching technique. Instinctive shooting is a technique eschewing sights and is often preferred by traditional archers (shooters of longbows and recurves). In either the split finger or three finger under case, the string is usually placed in either the first or second joint of the fingers.
The bow is then raised and drawn, with varying alignments used for vertical versus slightly canted bow positions. This is often one fluid motion for shooters of recurves and longbows which tends to vary from archer to archer, although for a compound shooter, there is often a slightly-jerky movement occurring during the drawback of the arrow at around midpoint where the draw weight is at its maximum, before relaxing into a comfortable stable full draw position. The string hand is drawn towards the face, where it should rest lightly at the chosen fixed anchor point. This point is consistent from shot to shot and is usually at the corner of the mouth, on the chin, to the cheek, or to the ear, depending upon one's preferred shooting style. The bow arm is held outwards toward the target. The elbow of this arm should be rotated so that the inner elbow is perpendicular to the ground, though archers with hyper extendable elbows tend to angle the inner elbow toward the ground as exemplified by the Korean archer Jang Yong-Ho.
In modern form, the archer stands erect, forming a "T". The archer's lower trapezius muscles are used to pull the arrow to the anchor point. Some modern bows will be equipped with a mechanical device, called a clicker, which produces a clicking sound when the archer reaches the correct draw length. In contrast, traditional English Longbow shooters step "into the bow", exerting force with both the bow arm and the string hand arm simultaneously, especially when using bows having draw weights from 100 lbs to over 175 lbs. Heavily-stacked traditional bows (recurves, long bows, and the like) are released immediately upon reaching full draw at maximum weight, whereas compound bows reach their maximum weight in or around mid-draw, dropping holding weight significantly at full draw. Compound bows are often held at full draw for a short time to achieve maximum accuracy.
The arrow is typically released by relaxing the fingers of the drawing hand (see Bow draw), or triggering the mechanical release aid. Usually the release aims to keep the drawing arm rigid, the bow hand relaxed, and the arrow is moved back using the back muscles, as opposed to using just arm motions. An archer should also pay attention to the recoil or follow through of his or her body, as it may indicate problems with form (technique) that affect accuracy.
There are two main forms of aiming in archery: using a mechanical or fixed sight or barebow. Barebow aiming methods include Gap, Split Vision, Point of Aim, String Walking, Face Walking and Instinctive aiming.
Mechanical sights can be affixed to the bow to aid in aiming. They can be as simple as a pin or optical with magnification. They usually also have a peep sight (rear sight) built into the string which aids in a consistent anchor point. Modern compound bows automatically limit the draw length which gives a consistent arrow velocity while traditional bows allow great variation in draw length. Mechanical methods to make a traditional bow's draw length consistent are sometimes used. Instinctive archers use a sight picture which includes the target, the bow, the hand, the arrow shaft and the arrow tip, as seen at the same time by the archer. With a fixed "anchor point" (where the string is brought to, or close to, the face), and a fully extended bow arm, successive shots taken with the sight picture in the same position will fall on the same point. This allows the archer to adjust aim with successive shots in order to achieve accuracy. Modern archery equipment usually includes sights. Instinctive aiming is used by many archers who use traditional bows. The two most common forms of a non-mechanical release are split-finger and three-under. Split-finger aiming requires the archer to place the index finger above the nocked arrow, while the middle and ring fingers are both placed below. Three-under aiming places the index, middle, and ring fingers under the nocked arrow. This technique allows the archer to better look down the arrow since the back of the arrow is closer to the dominant eye, and is commonly called "gun barreling" (referring to common aiming techniques used with firearms).
When using shortbows, or shooting from horseback, it is difficult to use the sight picture. The archer may look at the target but without including the weapon in the field of accurate view. Aiming involves a similar sort of hand/eye coordination which includes proprioception and motor/muscle memory between the mind/body connection that is used when throwing a baseball or shooting a basketball. With sufficient practice, such archers can normally achieve good practical accuracy for hunting or for war.[25] Aiming without a sight picture may allow more rapid shooting.
Currently Instinctive shooting is a term used to describe a style of shooting that includes the barebow aiming method that relies heavily upon the subconscious mind, proprioception and motor/muscle memory to make aiming adjustments while years ago the term was used to generalize and/or categorize those archers who did not use a mechanical or fixed sight.[26]
When a projectile is thrown by hand, the speed of the projectile is determined by the kinetic energy imparted by the thrower's muscles performing work. However, the energy must be imparted over a limited distance (determined by arm length) and therefore (because the projectile is accelerating) over a limited time, so the limiting factor is not work but rather power, which determined how much energy can be added in the limited time available. Power generated by muscles, however, is limited by Force-velocity relationship, and even at the optimal contraction speed for power production, total work done by the muscle will be less than half of what could be done if the muscle were contracting over the same distance at very slow speeds, resulting in less than 1/4 the projectile launch velocity possible without the limitations of the Force-velocity relationship.
When a bow is used, the muscles are able to perform work much more slowly, resulting in greater force and greater work done. This work is stored in the bow as elastic potential energy, and when the bowstring is released, this stored energy is imparted to the arrow much more quickly than can be delivered by the muscles, resulting in much higher velocity and, hence, greater distance. This same process is employed by frogs which use elastic tendons to increase jumping distance. In archery, some energy is dissipated through elastic hysteresis, reducing the overall amount released when the bow is shot. Of the energy remaining, some is dampened both by the limbs of the bow and the bowstring. Depending on the elasticity of the arrow, some of the energy is also absorbed by compressing the arrow, primarily because the release of the bowstring is rarely in line with the arrow shaft, causing it to flex out to one side.
This is because the bowstring accelerates faster than the archer's fingers can open, and consequently some sideways motion is imparted to the string, and hence arrow nock, as the power and speed of the bow pulls the string off the opening fingers. Even with a release aid mechanism some of this effect will usually be experienced, since the string always accelerates faster than the retaining part of the mechanism. This results in an in-flight oscillation of the arrow in which its center flexes out to one side and then the other repeatedly, gradually reducing as the arrow's flight proceeds; this can be clearly seen in high-speed photography of an arrow at discharge.
Modern arrows are made to a specified 'spine', or stiffness rating, to maintain matched flexing and hence accuracy of aim. This flexing can be a desirable feature, since, when the spine of the shaft is matched to the acceleration of the bow(string), the arrow bends or flexes around the bow and any arrow-rest, and consequently the arrow, and fletchings, have an un-impeded flight. This feature is known as the archer's paradox. It maintains accuracy, for if part of the arrow struck a glancing blow on discharge, some inconsistency would be present, and the excellent accuracy of modern equipment would not be achieved.
The accurate flight of an arrow is dependent on its fletching. The arrow's manufacturer (a "fletcher") can arrange fletching to cause the arrow to rotate along its axis. This improves accuracy by evening pressure buildups that would otherwise cause the arrow to "plane" on the air in a random direction after shooting. Even though the arrow be made with extreme care, the slightest imperfection, or air movement, will cause some unbalanced turbulence in air flow. Consequently, rotation creates an equalling of such turbulence, which, overall, maintains the intended direction of flight i.e. accuracy. This rotation is not to be confused with the rapid gyroscopic rotation of a rifle bullet. If the fletching is not arranged to induce rotation, it will still improve accuracy by causing a restoring drag any time the arrow tilts away from its intended direction of travel.
The innovative aspect of the invention of the bow and arrow was the amount of power delivered to an extremely small area by the arrow. The huge ratio of length vs cross sectional area coupled with velocity made the arrow orders of magnitude more powerful than any other hand held weapon until firearms were invented. Arrows may be designed to spread or concentrate force, depending on their applications. Practice arrows, for instance, can use a blunt tip that spreads the force over a wider area to reduce the risk of injury or limit penetration. Arrows designed to pierce armor in the Middle Ages would use a very narrow and sharp tip ("bodkinhead") to concentrate the force. Arrows used for hunting would use a narrow tip ("broadhead") that widens further, to facilitate both penetration and a large wound.
Using archery to take game animals is known as bowhunting. Bowhunting differs markedly from hunting with firearms as the distances between the hunter and the game are much shorter in order to ensure a humane kill. The skills and practices of bowhunting therefore emphasize very close approach to the prey, whether by still hunting, stalking, or waiting in a blind or treestand. In many countries, including much of the United States, bowhunting for large and small game is legal. Bowhunters generally enjoy longer seasons than are allowed with other forms of hunting such as black powder, shotgun, or rifle. Usually, compound bows are used for large game hunting and may feature fiber optic sights and other enhancements. Using a bow and arrow to take fish is known as bowfishing.
Competitive archery involves shooting arrows at a target for accuracy from a set distance or distances. This is the most popular form of competitive archery worldwide and is called target archery. A form particularly popular in Europe and America is field archery, shot at targets generally set at various distances in a wooded setting. Para-Archery is an adaptation of archery for athletes with a disability. It is governed by the International Archery Federation (FITA), and is one of the sports in the Summer Paralympic Games. There are also several other lesser-known and historical forms of archery, as well as archery novelty games.
Archery at the Open Directory Project
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