title
stringlengths 1
251
| section
stringlengths 0
6.12k
| text
stringlengths 0
716k
|
|---|---|---|
AK-47 | Short description | The AK-47, officially known as the Avtomat Kalashnikova (; also known as the Kalashnikov or just AK), is an assault rifle that is chambered for the 7.62×39mm cartridge. Developed in the Soviet Union by Russian small-arms designer Mikhail Kalashnikov, it is the originating firearm of the Kalashnikov (or "AK") family of rifles. After more than seven decades since its creation, the AK-47 model and its variants remain one of the most popular and widely used firearms in the world.
Design work on the AK-47 began in 1945. It was presented for official military trials in 1947, and, in 1948, the fixed-stock version was introduced into active service for selected units of the Soviet Army. In early 1949, the AK was officially accepted by the Soviet Armed Forces and used by the majority of the member states of the Warsaw Pact.
The model and its variants owe their global popularity to their reliability under harsh conditions, low production cost (compared to contemporary weapons), availability in virtually every geographic region, and ease of use. The AK has been manufactured in many countries and has seen service with armed forces as well as irregular forces and insurgencies throughout the world. , "of the estimated 500 million firearms worldwide, approximately 100 million belong to the Kalashnikov family, three-quarters of which are AK-47s". The model is the basis for the development of many other types of individual, crew-served, and specialized firearms. |
AK-47 | History | History |
AK-47 | Origins | Origins
During World War II, the Sturmgewehr 44 rifle used by German forces made a deep impression on their Soviet counterparts. The select-fire rifle was chambered for a new intermediate cartridge, the 7.92×33mm Kurz, and combined the firepower of a submachine gun with the range and accuracy of a rifle. On 15 July 1943, an earlier model of the Sturmgewehr was demonstrated before the People's Commissariat of Arms of the USSR. The Soviets were impressed with the weapon and immediately set about developing an intermediate caliber fully automatic rifle of their own, to replace the PPSh-41 submachine guns and outdated Mosin–Nagant bolt-action rifles that armed most of the Soviet Army.
The Soviets soon developed the 7.62×39mm M43 cartridge, used in the semi-automatic SKS carbine and the RPD light machine gun. Shortly after World War II, the Soviets developed the AK-47 rifle, which quickly replaced the SKS in Soviet service. Introduced in 1959, the AKM is a lighter stamped steel version and the most ubiquitous variant of the entire AK series of firearms. In the 1960s, the Soviets introduced the RPK light machine gun, an AK-type weapon with a stronger receiver, a longer heavy barrel, and a bipod, that eventually replaced the RPD light machine gun. |
AK-47 | Concept | Concept
Mikhail Kalashnikov began his career as a weapon designer in 1941 while recuperating from a shoulder wound that he received during the Battle of Bryansk. Kalashnikov himself stated..."I was in the hospital, and a soldier in the bed beside me asked: 'Why do our soldiers have only one rifle for two or three of our men when the Germans have automatics?' So I designed one. I was a soldier, and I created a machine gun for a soldier. It was called an Avtomat Kalashnikova, the automatic weapon of Kalashnikov—AK—and it carried the year of its first manufacture, 1947."
The AK-47 is best described as a hybrid of previous rifle technology innovations. "Kalashnikov decided to design an automatic rifle combining the best features of the American M1 Garand and the German StG 44." Kalashnikov's team had access to these weapons and did not need to "reinvent the wheel". Kalashnikov himself observed: "A lot of Russian Army soldiers ask me how one can become a constructor, and how new weaponry is designed. These are very difficult questions. Each designer seems to have his own paths, his own successes and failures. But one thing is clear: before attempting to create something new, it is vital to have a good appreciation of everything that already exists in this field. I myself have had many experiences confirming this to be so."
Some claimed that Kalashnikov copied designs like Bulkin's TKB-415 or Simonov's AVS-31. |
AK-47 | Early designs | Early designs
Kalashnikov started work on a submachine gun design in 1942 and a light machine gun design in 1943. Early in 1944, Kalashnikov was given some 7.62×39mm M43 cartridges and informed that other designers were working on weapons for this new Soviet small-arms cartridge. It was suggested that a new weapon might well lead to greater things. He then undertook work on the new rifle. In 1944, he entered a design competition with this new 7.62×39mm, semi-automatic, gas-operated, long-stroke piston carbine, strongly influenced by the American M1 Garand. The new rifle was in the same class as the SKS-45 carbine, with a fixed magazine and gas tube above the barrel. However, the new Kalashnikov design lost out to a Simonov design.
In 1946, a new design competition was initiated to develop a new rifle. Kalashnikov submitted a gas-operated rifle with a short-stroke gas piston above the barrel, a breechblock mechanism similar to his 1944 carbine, and a curved 30-round magazine. Kalashnikov's rifles, the AK-1 (with a milled receiver) and AK-2 (with a stamped receiver) proved to be reliable weapons and were accepted to a second round of competition along with other designs.
These prototypes (also known as the AK-46) had a rotary bolt, a two-part receiver with separate trigger unit housing, dual controls (separate safety and fire selector switches), and a non-reciprocating charging handle located on the left side of the weapon. This design had many similarities to the StG 44. In late 1946, as the rifles were being tested, one of Kalashnikov's assistants, Aleksandr Zaitsev, suggested a major redesign to improve reliability. At first, Kalashnikov was reluctant, given that their rifle had already fared better than its competitors. Eventually, however, Zaitsev managed to persuade Kalashnikov.
thumb|Trail prototype weapon with slab-sided steel magazine
In November 1947, the new prototypes (AK-47s) were completed. The rifle used a long-stroke gas piston above the barrel. The upper and lower receivers were combined into a single receiver. The selector and safety were combined into a single control lever/dust cover on the right side of the rifle and the bolt handle was attached to the bolt carrier. This simplified the design and production of the rifle. The first army trial series began in early 1948. The new rifle proved to be reliable under a wide range of conditions and possessed convenient handling characteristics. In 1949, it was adopted by the Soviet Army as the "7.62 mm Kalashnikov rifle (AK)". |
AK-47 | Further development | Further development
thumb|AKMS with a stamped Type 4B receiver (top) and an AK-47 with a milled Type 2A receiver
There were many difficulties during the initial phase of production. The first production models had stamped sheet metal receivers with a milled trunnion and butt stock insert and a stamped body. Difficulties were encountered in welding the guide and ejector rails, causing high rejection rates. Instead of halting production, a heavy2.6 lb milled from 6 lb stock. This was about 2.2 lb heavier than the stamped receiver. machined receiver was substituted for the sheet metal receiver. Even though production of these milled rifles started in 1951, they were officially referred to as AK-49, based on the date their development started, but they are widely known in the collectors' and current commercial market as "Type 2 AK-47". This was a more costly process, but the use of machined receivers accelerated production as tooling and labor for the earlier Mosin–Nagant rifle's machined receiver were easily adapted. Partly because of these problems, the Soviets were not able to distribute large numbers of the new rifles to soldiers until 1956. During this time, production of the interim SKS rifle continued.
Once the manufacturing difficulties of non-milled receivers had been overcome, a redesigned version designated the AKM (M for "modernized" or "upgraded"; in Russian: []) was introduced in 1959. This new model used a stamped sheet metal receiver and featured a slanted muzzle brake on the end of the barrel to compensate for muzzle rise under recoil. In addition, a hammer retarder was added to prevent the weapon from firing out of battery (without the bolt being fully closed), during rapid or fully automatic fire. This is also sometimes referred to as a "cyclic rate reducer", or simply "rate reducer", as it also has the effect of reducing the number of rounds fired per minute during fully automatic fire. The rifle was also roughly one-third lighter than the previous model.
Receiver type Description Type 1A/B The original stamped receiver for the AK-47 was first produced in 1948 and adopted in 1949. The 1B was modified for an underfolding stock with a large hole present on each side to accommodate the hardware for the under folding stock. Type 2A/B The first milled receiver was made from steel forging. It went into production in 1951 and production ended in 1957. The Type 2A has a distinctive socketed metal "boot" connecting the butt stock to the receiver and the milled lightning cut on the sides runs parallel to the barrel. Type 3A/B "Final" version of the AK milled receiver made from steel bar stock. It went into production in 1955. The most ubiquitous example of the AK milled receiver. The milled lightning cut on the sides is slanted to the barrel axis. Type 4A/B AKM receiver stamped from a smooth sheet of steel supported extensively by pins and rivets. It went into production in 1959. Overall, the most-used design in the construction of AK-series rifles.
Most licensed and unlicensed productions of the Kalashnikov assault rifle abroad were of the AKM variant, partially due to the much easier production of the stamped receiver. This model is the most commonly encountered, having been produced in much greater quantities. All rifles based on the Kalashnikov design are often colloquially referred to as "AK-47s" in the West and some parts of Asia, although this is only correct when applied to rifles based on the original three receiver types. In most former Eastern Bloc countries, the weapon is known simply as the "Kalashnikov" or "AK". The differences between the milled and stamped receivers includes the use of rivets rather than welds on the stamped receiver, as well as the placement of a small dimple above the magazine well for stabilization of the magazine. |
AK-47 | Replacement | Replacement
In 1974, the Soviets began replacing their AK-47 and AKM rifles with a newer design, the AK-74, which uses 5.45×39mm ammunition. This new rifle and cartridge had only started to be manufactured in Eastern European nations when the Soviet Union collapsed, drastically slowing the production of the AK-74 and other weapons of the former Soviet bloc. |
AK-47 | Design | Design
The AK-47 was designed to be a simple, reliable fully automatic rifle that could be manufactured quickly and cheaply, using mass production methods that were state of the art in the Soviet Union during the late 1940s. The AK-47 uses a long-stroke gas system generally associated with high reliability in adverse conditions. The large gas piston, generous clearance between moving parts, and tapered cartridge case design allow the gun to endure large amounts of foreign matter and fouling without failing to cycle. |
AK-47 | Cartridge | Cartridge
thumb|Wound Profiles of Russian small-arms ammunition compiled by Dr. Martin Fackler on behalf of the US militaryThe AK fires the 7.62×39mm cartridge with a muzzle velocity of .
The cartridge weight is , and the projectile weight is . The original Soviet M43 bullets are 123-grain boat-tail bullets with a copper-plated steel jacket, a large steel core, and some lead between the core and the jacket. The AK has excellent penetration when shooting through heavy foliage, walls, or a common vehicle's metal body and into an opponent attempting to use these things as cover. The 7.62×39mm M43 projectile does not generally fragment when striking an opponent and has an unusual tendency to remain intact even after making contact with bone. The 7.62×39mm round produces significant wounding in cases where the bullet tumbles (yaws) in tissue, but produces relatively minor wounds in cases where the bullet exits before beginning to yaw. In the absence of yaw, the M43 round can pencil through tissue with relatively little injury.
Most, if not all, of the 7.62×39mm ammunition found today is of the upgraded M67 variety. This variety deleted the steel insert, shifting the center of gravity rearward, and allowing the projectile to destabilize (or yaw) at about , nearly earlier in tissue than the M43 round. This change also reduces penetration in ballistic gelatin to ~ for the newer M67 round versus ~ for the older M43 round. However, the wounding potential of M67 is mostly limited to the small permanent wound channel the bullet itself makes, especially when the bullet yaws. |
AK-47 | Operating mechanism | Operating mechanism
thumb|The gas-operated mechanism of a Norinco AK-47
To fire, the operator inserts a loaded magazine, pulls back and releases the charging handle, and then pulls the trigger. In semi-automatic, the firearm fires only once, requiring the trigger to be released and depressed again for the next shot. In fully automatic, the rifle continues to fire automatically cycling fresh rounds into the chamber until the magazine is exhausted or pressure is released from the trigger. After ignition of the cartridge primer and propellant, rapidly expanding propellant gases are diverted into the gas cylinder above the barrel through a vent near the muzzle. The build-up of gases inside the gas cylinder drives the long-stroke piston and bolt carrier rearward and a cam guide machined into the underside of the bolt carrier, along with an ejector spur on the bolt carrier rail guide, rotates the bolt approximately 35° and unlocks it from the barrel extension via a camming pin on the bolt. The moving assembly has about of free travel, which creates a delay between the initial recoil impulse of the piston and the bolt unlocking sequence, allowing gas pressures to drop to a safe level before the seal between the chamber and the bolt is broken. The AK-47 does not have a gas valve; excess gases are ventilated through a series of radial ports in the gas cylinder. Unlike many other rifle platforms, such as the AR-15 platform, the Kalashnikov platform bolt locking lugs are chamfered allowing for primary extraction upon bolt rotation which aids reliable feeding and extraction, albeit not with that much force due to the short distance the bolt carrier travels before acting on the locking lug. The Kalashnikov platform then uses an extractor claw along with a fin shaped ejector to eject the spent cartridge case. |
AK-47 | Barrel | Barrel
thumb|AK-47 barrel and its distinctive gas block with a horizontal row of gas relief ports
The rifle received a barrel with a chrome-lined bore and four right-hand grooves at a 240 mm (1 in 9.45 in) or 31.5 calibers rifling twist rate. The gas block contains a gas channel that is installed at a slanted angle with the bore axis. The muzzle is threaded for the installation of various muzzle devices such as a muzzle brake or a blank-firing adaptor. |
AK-47 | Gas block | Gas block
The gas block of the AK-47 features a cleaning rod capture or sling loop. Gas relief ports that alleviate gas pressure are placed horizontally in a row on the gas cylinder. |
AK-47 | Fire selector | Fire selector
thumb|left|upright|Việt Cộng soldier armed with an AK-47 with the fire selector in the safe setting
The fire selector is a large lever located on the right side of the rifle; it acts as a dust cover and prevents the charging handle from being pulled fully to the rear when it is on safe. It is operated by the shooter's right fore-fingers and has three settings: safe (up), full-auto (center), and semi-auto (down). The reason for this is that a soldier under stress will push the selector lever down with considerable force, bypassing the full-auto stage and setting the rifle to semi-auto. To set the AK-47 to full-auto requires the deliberate action of centering the selector lever. To operate the fire selector lever, right-handed shooters have to briefly remove their right hand from the pistol grip, which is ergonomically sub-optimal. Some AK-type rifles also have a more traditional selector lever on the left side of the receiver, just above the pistol grip. This lever is operated by the shooter's right thumb and has three settings: safe (forward), full-auto (center), and semi-auto (backward). |
AK-47 | Sights | Sights
thumb|Rear sight of a Chinese Type 56, featuring settings and omission of a battle zero setting
The AK-47 uses a notched rear tangent iron sight calibrated in increments from . The front sight is a post adjustable for elevation in the field. Horizontal adjustment requires a special drift tool and is done by the armory before the issue or if the need arises by an armorer after the issue. The sight line elements are approximately over the bore axis. The "point-blank range" battle zero setting "П" standing for постоянная (constant) on the 7.62×39mm AK-47 rear tangent sight element corresponds to a zero. These settings mirror the Mosin–Nagant and SKS rifles, which the AK-47 replaced. For the AK-47 combined with service cartridges, the 300 m battle zero setting limits the apparent "bullet rise" within approximately relative to the line of sight. Soldiers are instructed to fire at any target within this range by simply placing the sights on the center of mass (the belt buckle, according to Russian and former Soviet doctrine) of the enemy target. Any errors in range estimation are tactically irrelevant, as a well-aimed shot will hit the torso of the enemy soldier. Some AK-type rifles have a front sight with a flip-up luminous dot that is calibrated at , for improved night fighting. |
AK-47 | Furniture | Furniture
The AK-47 was originally equipped with a buttstock, handguard, and an upper heat guard made from solid wood. With the introduction of the Type 3 receiver the buttstock, lower handguard, and upper heat guard were manufactured from birch plywood laminates. Such engineered woods are stronger and resist warping better than the conventional one-piece patterns, do not require lengthy maturing, and are cheaper. The wooden furniture was finished with the Russian amber shellac finishing process. AKS and AKMS models featured a downward-folding metal butt-stock similar to that of the German MP40 submachine-gun, for use in the restricted space in the BMP infantry combat vehicle, as well as by paratroops. All 100 series AKs use plastic furniture with side-folding stocks. |
AK-47 | Magazines | Magazines
thumb|"Bakelite" rust-colored steel-reinforced 30-round plastic box 7.62×39mm AK magazines. Three magazines have an "arrow in triangle" Izhmash arsenal mark on the bottom right. The other magazine has a "star" Tula arsenal mark on the bottom right
The standard magazine capacity is 30 rounds. There are also 10-, 20-, and 40-round box magazines, as well as 75-round drum magazines.
The AK-47's standard 30-round magazines have a pronounced curve that allows them to smoothly feed ammunition into the chamber. Their heavy steel construction combined with "feed-lips" (the surfaces at the top of the magazine that control the angle at which the cartridge enters the chamber) machined from a single steel billet makes them highly resistant to damage. These magazines are so strong that "Soldiers have been known to use their mags as hammers, and even bottle openers". This contributes to the AK-47 magazine being more reliable but makes it heavier than US and NATO magazines.
The early slab-sided steel AK-47 30-round detachable box magazines had sheet-metal bodies and weighed empty. The later steel AKM 30-round magazines had lighter sheet-metal bodies with prominent reinforcing ribs weighing empty. To further reduce weight, a lightweight magazine with an aluminum body with a prominent reinforcing waffle rib pattern weighing empty was developed for the AKM that proved to be too fragile, and the small issued amount of these magazines were quickly withdrawn from service. As a replacement steel-reinforced 30-round plastic 7.62×39mm box magazines were introduced. These rust-colored magazines weigh empty and are often mistakenly identified as being made of Bakelite (a phenolic resin), but were fabricated from two parts of AG-S4 molding compound (a glass-reinforced phenol-formaldehyde binder impregnated composite), assembled using an epoxy resin adhesive. Noted for their durability, these magazines did however compromise the rifle's camouflage and lacked the small horizontal reinforcing ribs running down both sides of the magazine body near the front that were added on all later plastic magazine generations. A second-generation steel-reinforced dark-brown (color shades vary from maroon to plum to near black) 30-round 7.62×39mm magazine was introduced in the early 1980s, fabricated from ABS plastic. The third generation steel-reinforced 30-round 7.62×39mm magazine is similar to the second generation, but is darker colored and has a matte non-reflective surface finish. The current issue is a steel-reinforced matte true black non- reflective surface finished 7.62×39mm 30-round magazine, fabricated from ABS plastic weighing empty.
Early steel AK-47 magazines are long; the later ribbed steel AKM and newer plastic 7.62×39mm magazines are about shorter.
The transition from steel to mainly plastic magazines yields a significant weight reduction and allows a soldier to carry more ammunition for the same weight.
Rifle Cartridge Weight of empty magazine Weight of loaded magazine Max. ammunition load* AK-47 (1949) 7.62×39mm slab-sided steel 30-rounds 11 magazines for 330 rounds AKM (1959) ribbed stamped-steel 30-rounds 12 magazines for 360 rounds AK-103 (1994) steel-reinforced plastic 30-rounds 13 magazines for 390 rounds
All 7.62×39mm AK magazines are backward compatible with older AK variants.
10.12 kg (22.3 lb) is the maximum amount of ammo that the average soldier can comfortably carry. It also allows for the best comparison of the three most common 7.62×39mm AK magazines.
Most Yugoslavian and some East German AK magazines were made with cartridge followers that hold the bolt open when empty; however, most AK magazine followers allow the bolt to close when the magazine is empty. |
AK-47 | Accessories | Accessories
thumb|left|AK-47 6H2 bayonet and scabbard
thumb|left|AK-47 with Kalashnikov grenade launcher mounted on the muzzle
Accessories supplied with the rifle include a long 6H3 bayonet featuring a long spear point blade. The AK-47 bayonet is installed by slipping the diameter muzzle ring around the muzzle and latching the handle down on the bayonet lug under the front sight base.
All current model AKM rifles can mount under-barrel 40 mm grenade launchers such as the GP-25 and its variants, which can fire up to 20 rounds per minute and have an effective range of up to 400 meters. The main grenade is the VOG-25 (VOG-25M) fragmentation grenade which has a 6 m (9 m) (20 ft (30 ft)) lethality radius. The VOG-25P/VOG-25PM ("jumping") variant explodes above the ground.
The AK-47 can also mount a (rarely used) cup-type grenade launcher, the Kalashnikov grenade launcher that fires standard RGD-5 Soviet hand grenades. The maximum effective range is approximately 150 meters. This launcher can also be used to launch tear gas and riot control grenades.
All current AKs (100 series) and some older models have side rails for mounting a variety of scopes and sighting devices, such as the PSO-1 Optical Sniper Sight. The side rails allow for the removal and remounting of optical accessories without interfering with the zeroing of the optic. However, the 100 series side folding stocks cannot be folded with the optics mounted. |
AK-47 | Characteristics | Characteristics |
AK-47 | Service life | Service life
The AK-47 and its variants have been and are made in dozens of countries, with "quality ranging from finely engineered weapons to pieces of questionable workmanship." As a result, the AK-47 has a service/system life of approximately 6,000, to 10,000, to 15,000 rounds. The AK-47 was designed to be a cheap, simple, easy-to-manufacture rifle, perfectly matching Soviet military doctrine that treats equipment and weapons as disposable items. As units are often deployed without adequate logistical support and dependent on "battlefield cannibalization" for resupply, it is more cost-effective to replace rather than repair weapons.
The AK-47 has small parts and springs that need to be replaced every few thousand rounds. However, "Every time it is disassembled beyond the field stripping stage, it will take some time for some parts to regain their fit, and some parts may tend to shake loose and fall out when firing the weapon. Some parts of the AK-47 line are riveted together. Repairing these can be quite a hassle since the end of the rivet has to be ground off and a new one set after the part is replaced." |
AK-47 | Variants | Variants
thumb|7.62×39mm cartridges from Russia, China and Pakistan
Early variants (7.62×39mm)
Issue of 1948/49: Type 1: The very earliest models, stamped sheet metal receivers, are now very rare.
Issue of 1951: Type 2: Has a milled receiver. The barrel and chamber are chrome-plated to resist corrosion.
Issue of 1954/55: Type 3: Lightened, milled receiver variant. Rifle weight is .
AKS (AKS-47): Type 1, 2, or 3 receivers: Featured a downward under folding metal stock similar to that of the MP 40, for use in the restricted space of the BMP infantry combat vehicle, as well as for airborne troops.
AKN (AKSN): Night sight rail.
Modernized (7.62×39mm)
AKM: A simplified, lighter version of the AK-47; the Type 4 receiver is made from stamped and riveted sheet metal. A slanted muzzle device was added to reduce muzzle rise in automatic fire. The rifle weight is due to the lighter receiver. This is the most ubiquitous variant of the AK-47.
AKMS: Under-folding stock version of the AKM intended for airborne troops.
AKMN (AKMSN): Night scope rail.
AKML (AKMSL): Slotted flash suppressor and night scope rail.
RPK: Hand-held machine gun version with longer barrel and bipod. The variants—RPKS, RPKN (RPKSN), RPKL (RPKSL)—mirror AKM variants. The "S" variants have a side-folding wooden stock.
Foreign Variants (7.62×39mm)
Type 56: Chinese assault rifle based on the . Still in production primarily for export markets.
For the further developed AK models, see Kalashnikov rifles. |
AK-47 | Production | Production
Manufacturing countries of AK-47 and its variants in alphabetical order.
Country Military variant(s) Albania Automatiku Shqiptar 1978 model 56 (ASH-78 Tip-1) made at Poliçan Arsenal (copy of Type 56 based on AKM rifle); model 56 Tip-2, copy of RPK; model 56 Tip-3 hybrid for multi-purpose roles with secondary rifle and grenade launcher capability; 1982 model (ASH-82) copy of AKMS. Several other versions of the AKMS have been produced mainly with short barrels similar to Soviet AKS-74U for special forces, tank & armoured crew and for helicopter pilots and police. There have also been modified ASh-82 (AKMS) with SOPMOD accessories, mainly for Albania's special forces RENEA & exports. Armenia K-3 (bullpup, 5.45×39mm) Azerbaijan Khazri (AK-74M) Bangladesh Chinese Type 56 Bulgaria AKK/AKKS (Type 3 AK-47/w. side-folding buttstock); AKKMS (AKMS), AKKN-47 (fittings for NPSU night sights); AK-47M1 (Type 3 with black polymer furniture); AK-47MA1/AR-M1 (same as -M1, but in 5.56mm NATO); AKS-47M1 (AKMS in 5.56×45mm NATO); AKS-47S (AK-47M1, short version, with East German folding stock, laser aiming device); AKS-47UF (short version of -M1, Russian folding stock), AR-SF (same as −47UF, but 5.56mm NATO); AKS-93SM6 (similar to −47M1, cannot use grenade launcher); and RKKS (RPK), AKT-47 (.22 rimfire training rifle) Cambodia Chinese Type 56, Soviet AK-47, and AKM China Type 56 Colombia Galil ACE, Galil Córdova Croatia APS-95 Cuba AKM East Germany MPi-K/MPi-KS (AK-47/AKS); MPi-KM (AKM; wooden and plastic stock), MPi-KMS-72 (side-folding stock), MPi-KMS-K (carbine); MPi-AK-74N (AK-74), MPi-AKS-74N (side-folding stock), MPi-AKS-74NK (carbine); KK-MPi Mod.69 (.22 LR select-fire trainer) Egypt AK-47, Misr rifle (AKMS), Maadi ARM (AKM) Ethiopia AK-47, AK-103 (manufactured locally at the State-run Gafat Armament Engineering Complex as the Et-97/1) Finland Rk 62, Valmet M76 (other names Rk 62 76, M62/76), Valmet M78 (light machine gun), Rk 95 Tp Hungary AK-55 (domestic manufacture of the 2nd Model AK-47); AKM-63 (also known as AMD-63 in the US; modernized AK-55), AMD-65M (modernized AKM-63, shorter barrel and side-folding stock), AMP-69 (rifle grenade launcher); AK-63F/D (other name AMM/AMMSz), AK-63MF (modernized); NGM-81 (5.56×45mm NATO; fixed and under-folding stock) India INSAS (fixed and side-folding stock), KALANTAK (carbine), INSAS light machine gun (fixed and side-folding stock), a local unlicensed version with carbon fibre furniture designated as AK-7; and Trichy Rifle 7.62 mm manufactured by Ordnance Factory Tiruchirappalli of Ordnance Factories Board Iran KLS/KLF (AK-47/AKS), KLT (AKMS) Iraq Tabuk Sniper Rifle, Tabuk Rifle (with fixed or underfolding stock, outright clones of Yugoslavian M70 rifles series), Tabuk Short Rifle (carbine) Israel IMI Galil: AR (battle rifle), ARM (rifle/light machine gun), SAR (carbine), MAR (compact carbine), Sniper (sniper rifle), SR-99 (sniper rifle); and Galil ACE Italy Bernardelli VB-STD/VB-SR (Galil AR/SAR) Nigeria Produced by DICON as OBJ-006 North Korea Type 58A/B (Type 3 AK-47/w. stamped steel folding stock), Type 68A/B (AKM/AKMS), Type 88A/B-2 (AK-74/AKS-74/w. top folding stock) Pakistan Reverse engineered by hand and machine in Pakistan's highland areas (see Khyber Pass Copy) near the border of Afghanistan; more recently the Pakistan Ordnance Factories started the manufacture of an AK-47/AKM clone called PK-10 Poland PmK (kbk AK) / PmKS (kbk AKS), Kalashnikov SMG name change to Kbk AK, Kalashnikov Carbine in 1960s, (AK-47/AKS); kbkg wz. 1960 (rifle grenade launcher), kbkg wz. 1960/72 (modernized); kbk AKM / kbk AKMS (AKM/AKMS); kbk wz. 1988 Tantal (5.45×39mm), skbk wz. 1989 Onyks (compact carbine); kbs wz. 1996 Beryl (5.56×45mm), kbk wz. 1996 Mini-Beryl (compact carbine) Romania PM md. 63/65 (AKM/AKMS), PM md. 80, PM md. 90, collectively exported under the umbrella name AIM or AIMS; PA md. 86 (AK-74) exported as the AIMS-74; PM md. 90 short barrel, PA md. 86 short barrel exported as the AIMR; PSL (designated marksman rifle; other names PSL-54C, Romak III, FPK and SSG-97) South Africa R4 rifle, Truvelo Raptor, Vektor CR-21 (bullpup) Sudan MAZ (based on the Type 56) Türkiye SAR 15T, SAR 308 Ukraine Vepr (bullpup, 5.45×39mm), Malyuk (bullpup) United States Century Arms: C39 (AK-47 var.), RAS47 (AKM var.), and C39v2 (AK-47 var.), InterOrdnance: AKM247 (AKM var.) M214 (pistol), Palmetto State Armory: PSAK-47 (AKM var.), Arsenal Inc: SA M-7 (AK-47 var.), Destructive Devices Industries: DDI 47S (AKM var.) DDI 47M (AK-47 var), Rifle Dynamics: RD700 and other custom build AK / AKM guns Vietnam AKM-1 (AKM), TUL-1 (RPK), Galil Ace 31/32, STV rifle Venezuela License granted, factory under construction Yugoslavia/Serbia M64, M70, M72, M76, M77, M80, M82, M85, M90, M91, M92, M99, M21
A private company Kalashnikov Concern (formerly Izhmash) from Russia has repeatedly claimed that the majority of foreign manufacturers are producing AK-type rifles without proper licensing. |
AK-47 | Accuracy potential | Accuracy potential |
AK-47 | US military method | US military method
The AK-47's accuracy is generally sufficient to hit an adult male torso out to about , though even experts firing from prone or bench rest positions at this range were observed to have difficulty placing ten consecutive rounds on target. Later designs did not significantly improve the rifle's accuracy. An AK can fire a 10-shot group of at , and at The newer stamped-steel receiver AKM models, while more rugged and less prone to metal fatigue, are less accurate than the forged/milled receivers of their predecessors: the milled AK-47s are capable of shooting groups at , whereas the stamped AKMs are capable of shooting groups at .
The best shooters can hit a man-sized target at within five shots (firing from a prone or bench rest position) or ten shots (standing).: (under the default conditions of no wind and sea level atmospheric pressure, ).
The single-shot hit-probability on the NATO E-type Silhouette Target (a human upper body half and head silhouette) of the AK-47 and the later developed AK-74, M16A1, and M16A2 rifles were measured by the US military under ideal proving ground conditions in the 1980s as follows:
thumb|75 px|NATO E-type Silhouette Target
+Single-shot hit-probability on Crouching Man (NATO E-type Silhouette) TargetRifleChamberingHit-probability (With no range estimation or aiming errors) 50 m 100 m 200 m 300 m 400 m 500 m 600 m 700 m 800 mAK-47 (1949)7.62×39mm100%100%99%94%82%67%54%42%31%AK-74 (1974)5.45×39mm100%100%100%99%93%81%66%51%34%M16A1 (1967)5.56×45mm NATO M193100%100%100%100%96%87%73%56%39%M16A2 (1982)5.56×45mm NATO SS109/M855100%100%100%100%98%90%79%63%43%
Under worst field exercise circumstances, the hit probabilities for all the tested rifles were drastically reduced, from 34% at 50m down to 3–4% at 600m with no significant differences between weapons at each range. |
AK-47 | Russian method | Russian method
The following table represents the Russian circular error probable method for determining accuracy, which involves drawing two circles on the target, one for the maximum vertical dispersion of hits and one for the maximum horizontal dispersion of hits. They then disregard the hits on the outer part of the target and only count half of the hits (50% or R50) on the inner part of the circles. This significantly reduces the overall diameter of the groups. They then use both the vertical and horizontal measurements of the reduced groups to measure accuracy. When the R50 results are doubled, the hit probability increases to 93.7%.
thumb|right|Circular error probable 20 hits distribution example
+AK-47 semi-automatic and short burst dispersion with 57-N-231 steel core service ammunitionRangeVertical accuracy of fire (R50) semi-automaticHorizontal accuracy of fire (R50) semi-automaticVertical accuracy of fire (R50) short burstHorizontal accuracy of fire (R50) short burstRemaining bullet energyRemaining bullet velocity
R50 means the closest 50 percent of the shot group will all be within a circle of the mentioned diameter.
The vertical and horizontal mean (R50) deviations with service ammunition at for AK platforms are.
+SKS, AK-47, AKM, and AK-74 dispersion at Manual on small business. 7.62-mm modernized Kalashnikov assault rifle (AKM and AKMS). – 3rd ed. – Moscow: Military Publishing, 1983. – 160 p., Ill.RifleFiring modeVertical accuracy of fire (R50)Horizontal accuracy of fire (R50)SKS (1945)semi-automaticAK-47 (1949)semi-automaticAK-47 (1949)short burstAKM (1959)short burstAK-74 (1974)short burst |
AK-47 | Users | Users
thumb|A map of current AK users (including derivative and modernized variants in orange and purple) |
AK-47 | Current | Current
− Type 56 variant.
− EKAM: The counter-terrorist unit of the Hellenic Police
− Type 58 variant
– Locally made as well as being in service with the Army
− Used by Thahan Phran
|
AK-47 | Non-state current | Non-state current
ELN
FARC dissidents
− Captured from the Syrian Army
Karen National Defence Organisation
Karen National Liberation Army
Kurdistan Workers Party
National Movement for the Liberation of Azawad
New People's Army
Syrian opposition
Ta'ang National Liberation Army |
AK-47 | Former | Former
− MPi-K (AK-47) and MPi-KM (AKM)
− Passed on to the unified Vietnamese state
− Used by the Panama Defense Forces
− Replaced by the AKM and AK-74
− Captured rifles were issued to ARVN irregular units |
AK-47 | Non-state former | Non-state former
Afghan mujahideen − CIA supplied Egyptian and Chinese variants
Contras
Farabundo Martí National Liberation Front
Iraqi insurgents
Khmer Rouge
Liberation Tigers of Tamil Eelam
Malayan National Liberation Army
Moro National Liberation Front
Northern Alliance
Provisional Irish Republican Army − Supplied by Libya
RENAMO
Revolutionary Armed Forces of Colombia
Viet Cong
Vigorous Burmese Student Warriors |
AK-47 | Illicit trade | Illicit trade
thumb|AK-47 copies confiscated from Somali pirates by Finnish mine-layer during Operation Atalanta, photographed in Manege Military Museum. The stocks are missing on the top three AKs.
Throughout the world, the AK and its variants are commonly used by governments, revolutionaries, terrorists, criminals, and civilians alike. In some countries, such as Somalia, Rwanda, Mozambique, Congo, and Tanzania, the prices for Black Market AKs are between $30 and $125 per weapon and prices have fallen in the last few decades due to mass counterfeiting. In Kenya, "an AK-47 fetches five head of cattle (about 10,000 Kenya shillings or 100 US dollars) when offered for barter, but costs almost half that price when cash is paid". There are places around the world where AK-type weapons can be purchased on the black market "for as little as $6, or traded for a chicken or a sack of grain".
The AK-47 has also spawned a cottage industry of sorts and has been copied and manufactured (one gun at a time) in small shops around the world (see Khyber Pass Copy). The estimated numbers of AK-type weapons vary greatly. The Small Arms Survey suggests that "between 70 and 100 million of these weapons have been produced since 1947". The World Bank estimates that out of the 500 million total firearms available worldwide, 100 million are of the Kalashnikov family, and 75 million are AK-47s. Because AK-type weapons have been made in many countries, often illicitly, it is impossible to know how many exist. |
AK-47 | Conflicts | Conflicts
The AK-47 has been used in the following conflicts:
1940s
Malayan Emergency (1948−1960)
1950s
Hungarian Revolution (1956)
Vietnam War (1955–1975)
Laotian Civil War (1959–1975)
1960s
Congo Crisis (1960–1965)
Portuguese Colonial War (1961–1974)
Rhodesian Bush War (1964–1979)
The Troubles (late 1960s–1998)
Communist insurgency in Thailand (1965–1983)
South African Border War (1966–1990)
India-China clashes (1967)
Cambodian Civil War (1968–1975)
Communist insurgency in Malaysia (1968–1989)
Moro conflict (1968−2019)
1970s
Yom Kippur War (1973)
Ethiopian Civil War (1974–1991)
Western Sahara War (1975–1991)
Cambodian–Vietnamese War (1978–1989)
Chadian–Libyan War (1978–1987)
Soviet–Afghan War (1979–1989)
1980s
1979 Kurdish rebellion in Iran
Iran–Iraq War (1980–1988)
Insurgency in Jammu and Kashmir (1988–present)
Sri Lankan Civil War (1983–2009)
United States invasion of Grenada (1983)
South Lebanon conflict (1985–2000)
Lord's Resistance Army insurgency (1987–present)
United States invasion of Panama (1989)
1990s
KDPI insurgency (1989–1996)
Tuareg rebellion (1990–1995)
Gulf War (1990–1991)
Somali Civil War (1991–present)
Yugoslav Wars (1991–2001)
Burundian Civil War (1993–2005)
First Chechen War (1994−1996)
Republic of the Congo Civil War (1997–1999)
Kargil War (1999)
2000s
War in Afghanistan (2001–2021)
Iraq War (2003–2011)
South Thailand insurgency (2004–present)
Mexican drug war (2006–present)
2010s
Libyan Civil War (2011)
Syrian civil war (2011–present)
Iraqi insurgency (2011–2013)
Central African Republic Civil War (2012–present)
Mali War (2012–present)
Russo-Ukrainian War (2014–present)
Western Iran clashes (2016–present)
2020s
Second Nagorno-Karabakh War (2020)
Tigray War (2020–2022)
Myanmar civil war (2021–present)
Russian invasion of Ukraine (2022–present)
September–October 2022 attacks on Iraqi Kurdistan
Gaza war (2023–present) |
AK-47 | Cultural influence and impact | Cultural influence and impact
thumb|The AK-47 on the flag of Mozambique
thumb|The AK-47 on the former coat of arms of Burkina Faso
thumb|CIA Agent drawing of the alleged first westerner sighting of the AK-47 in 1953
During the Cold War, the Soviet Union and the People's Republic of China, as well as United States and other NATO nations supplied arms and technical knowledge to numerous countries and rebel forces around the world. During this time the Western countries used relatively expensive automatic rifles, such as the FN FAL, the HK G3, the M14, and the M16. In contrast, the Russians and Chinese used the AK-47; its low production cost and ease of manufacture allow them to make AKs in vast numbers.
In the pro-communist states, the AK-47 became a symbol of the Third World revolution. They were utilized in the Cambodian Civil War and the Cambodian–Vietnamese War. During the 1980s, the Soviet Union became the principal arms dealer to countries embargoed by Western nations, including Middle Eastern nations such as Libya and Syria, which welcomed Soviet Union backing against Israel. After the fall of the Soviet Union, AK-47s were sold both openly and on the black market to any group with cash, including drug cartels and dictatorial states, and more recently they have been seen in the hands of Islamic groups such as Al-Qaeda, ISIL, and the Taliban in Afghanistan and Iraq, and FARC, Ejército de Liberación Nacional guerrillas in Colombia.
In Russia, the Kalashnikov is a tremendous source of national pride. "The family of the inventor of the world's most famous rifle, Mikhail Kalashnikov, has authorized German engineering company MMI to use the well-known Kalashnikov name on a variety of not-so-deadly goods." In recent years, Kalashnikov Vodka has been marketed with souvenir bottles in the shape of the AK-47 Kalashnikov. There are also Kalashnikov watches, umbrellas, and knives.
The Kalashnikov Museum (also called the AK-47 museum) opened on 4 November 2004 in Izhevsk, Udmurt Republic. This city is in the Ural Region of Russia. The museum chronicles the biography of General Kalashnikov and documents the invention of the AK-47. The museum complex of Kalashnikov's small arms, a series of halls, and multimedia exhibitions are devoted to the evolution of the AK-47 rifle and attracts 10,000 monthly visitors. Nadezhda Vechtomova, the museum director, stated in an interview that the purpose of the museum is to honor the ingenuity of the inventor and the hard work of the employees and to "separate the weapon as a weapon of murder from the people who are producing it and to tell its history in our country".
On 19 September 2017 a monument of Kalashnikov was unveiled in central Moscow. A protester, later detained by police, attempted to unfurl a banner reading "a creator of weapons is a creator of death".
The proliferation of this weapon is reflected by more than just numbers. The AK-47 is included on the flag of Mozambique and its emblem, an acknowledgment that the country gained its independence in large part through the effective use of their AK-47s. It is also found in the coats of arms of East Timor, Zimbabwe and the revolution era Burkina Faso, as well as in the flags of Hezbollah, Syrian Resistance, FARC-EP, the New People's Army, TKP/TIKKO and the International Revolutionary People's Guerrilla Forces.
US and Western Europe countries frequently associate the AK-47 with their enemies, both Cold War era and present-day. For example, Western works of fiction (movies, television, novels, video games) often portray criminals, gang members, insurgents, and terrorists using AK-47s as the weapon of choice. Conversely, throughout the developing world, the AK-47 can be positively attributed with revolutionaries against foreign occupation, imperialism, or colonialism.
In Ireland the AK-47 is associated with The Troubles due to its extensive use by republican paramilitaries during this period. In 2013, a decommissioned AK-47 was included in the A History of Ireland in 100 Objects collection.
The AK-47 made an appearance in US popular culture as a recurring focus in the Nicolas Cage film Lord of War (2005). Numerous monologues in the movie focus on the weapon, and its effects on global conflict and the gun running market.
In Iraq and Afghanistan, private military company contractors from the UK and other countries used the AK-47 and its variants along with Western firearms such as the AR-15.
In 2006, the Colombian musician and peace activist César López devised the escopetarra, an AK converted into a guitar. One sold for US$17,000 in a fundraiser held to benefit the victims of anti-personnel mines, while another was exhibited at the United Nations' Conference on Disarmament.
In Mexico, the AK-47 is known as "Cuerno de Chivo" (literally "Goat's Horn") because of its curved magazine design. It is one of the weapons of choice of Mexican drug cartels. It is sometimes mentioned in Mexican folk music lyrics. |
AK-47 | Gallery | Gallery |
AK-47 | See also | See also
Comparison of the AK-47 and M16
AK-12
PK machine gun
Draco |
AK-47 | Notes | Notes |
AK-47 | References | References |
AK-47 | Bibliography | Bibliography
|
AK-47 | Further reading | Further reading
Ружье. Оружие и амуниция, 1999/3, pp. 18–21 has an article about the AK-47 prototypes.
An article rejecting some of the alternative theories as to the authorship of the AK-47.
An article comparing the internals of the StG 44 and AK-47.
Transcription of the commission report on the testing round from the summer of 1947; no winner was selected at this point, but the commission held Kalashnikov's, Dementiev's and Bulkin's designs as most closely satisfying TTT number 3131.
Report/letter on the final round of testing, 27 December 1947, declaring Kalashnikov's design the winner.
Articles on the 1948 military trials. |
AK-47 | External links | External links
US Army Operator's Manual for the AK-47 Assault Rifle
&
Category:Weapons and ammunition introduced in 1947
Category:7.62×39mm assault rifles
Category:Infantry weapons of the Cold War
Category:Rifles of the Cold War
Category:Kalashnikov derivatives
Category:Assault rifles of the Soviet Union
Category:Kalashnikov Concern products
Category:Long stroke piston firearms |
AK-47 | Table of Content | Short description, History, Origins, Concept, Early designs, Further development, Replacement, Design, Cartridge, Operating mechanism, Barrel, Gas block, Fire selector, Sights, Furniture, Magazines, Accessories, Characteristics, Service life, Variants, Production, Accuracy potential, US military method, Russian method, Users, Current, Non-state current, Former, Non-state former, Illicit trade, Conflicts, Cultural influence and impact, Gallery, See also, Notes, References, Bibliography, Further reading, External links |
Atanasoff–Berry computer | short description | The Atanasoff–Berry computer (ABC) was the first automatic electronic digital computer. The device was limited by the technology of the day. The ABC's priority is debated among historians of computer technology, because it was neither programmable, nor Turing-complete. Conventionally, the ABC would be considered the first electronic ALU (arithmetic logic unit) which is integrated into every modern processor's design.
Its unique contribution was to make computing faster by being the first to use vacuum tubes to do arithmetic calculations. Prior to this, slower electro-mechanical methods were used by Konrad Zuse's Z1 computer, and the simultaneously developed Harvard Mark I. The first electronic, programmable, digital machine,Colossus and the German Lorenz Cypher. Anthony Sale, Bletchley Park Trust. the Colossus computer from 1943 to 1945, used similar tube-based technology as ABC. |
Atanasoff–Berry computer | Overview | Overview
Conceived in 1937, the machine was built by Iowa State College mathematics and physics professor John Vincent Atanasoff with the help of graduate student Clifford Berry. It was designed only to solve systems of linear equations and was successfully tested in 1942. However, its intermediate result storage mechanism, a paper card writer/reader, was not perfected, and when John Vincent Atanasoff left Iowa State College for World War II assignments, work on the machine was discontinued. The ABC pioneered important elements of modern computing, including binary arithmetic and electronic switching elements, but its special-purpose nature and lack of a changeable, stored program distinguish it from modern computers. The computer was designated an IEEE Milestone in 1990.
Atanasoff and Berry's computer work was not widely known until it was rediscovered in the 1960s, amid patent disputes over the first instance of an electronic computer. At that time ENIAC, that had been created by John Mauchly and J. Presper Eckert,John Presper Eckert Jr. and John W. Mauchly, Electronic Numerical Integrator and Computer, , filed 26 June 1947, issued 4 February 1964, and invalidated 19 October 1973 after court ruling on Honeywell v. Sperry Rand. was considered to be the first computer in the modern sense, but in 1973 a U.S. District Court invalidated the ENIAC patent and concluded that the ENIAC inventors had derived the subject matter of the electronic digital computer from Atanasoff. When, in the mid-1970s, the secrecy surrounding the British World War II development of the Colossus computers that pre-dated ENIAC, was liftedRandell, Brian, Colossus: Godfather of the Computer, 1977 (reprinted in The Origins of Digital Computers: Selected Papers, Springer-Verlag, New York, 1982) and Colossus was described at a conference in Los Alamos, New Mexico, in June 1976, John Mauchly and Konrad Zuse were reported to have been astonished. Report of the announcement of Colossus at the International Research Conference on the History of Computing, in Los Alamos, New Mexico, that began on 10 June 1976 |
Atanasoff–Berry computer | Design and construction | Design and construction
thumb|right|Diagram of the ABC pointing out its various components
According to Atanasoff's account, several key principles of the Atanasoff–Berry computer were conceived in a sudden insight after a long nighttime drive to Rock Island, Illinois, during the winter of 1937–38. The ABC innovations included electronic computation, binary arithmetic, parallel processing, regenerative capacitor memory, and a separation of memory and computing functions. The mechanical and logic design was worked out by Atanasoff over the next year. A grant application to build a proof of concept prototype was submitted in March 1939 to the Agronomy department, which was also interested in speeding up computation for economic and research analysis. $5,000 of further funding () to complete the machine came from the nonprofit Research Corporation of New York City.
The ABC was built by Atanasoff and Berry in the basement of the physics building at Iowa State College from 1939 to 1942. The initial funds were released in September, and the 11-tube prototype was first demonstrated in October 1939. A December demonstration prompted a grant for construction of the full-scale machine. The ABC was built and tested over the next two years. A January 15, 1941, story in the Des Moines Register announced the ABC as "an electrical computing machine" with more than 300 vacuum tubes that would "compute complicated algebraic equations" (but gave no precise technical description of the computer). The system weighed more than . It contained approximately of wire, 280 dual-triode vacuum tubes, 31 thyratrons, and was about the size of a desk.
It was not programmable, which distinguishes it from more general machines of the same era, such as Konrad Zuse's 1941 Z3 (or earlier iterations) and the Colossus computers of 1943–1945. Nor did it implement the stored-program architecture, first implemented in the Manchester Baby of 1948, required for fully general-purpose practical computing machines.
thumb|Add-subtract module (reconstructed) from Atanasoff–Berry computer
The machine was, however, the first to implement:
Using vacuum tubes, rather than wheels, ratchets, mechanical switches, or telephone relays, allowing for greater speed than previous computers
Using capacitors for memory, rather than mechanical components, allowing for greater speed and density
The memory of the Atanasoff–Berry computer was a system called regenerative capacitor memory, which consisted of a pair of drums, each containing 1600 capacitors that rotated on a common shaft once per second. The capacitors on each drum were organized into 32 "bands" of 50 (30 active bands and two spares in case a capacitor failed), giving the machine a speed of 30 additions/subtractions per second. Data was represented as 50-bit binary fixed-point numbers. The electronics of the memory and arithmetic units could store and operate on 60 such numbers at a time (3000 bits).
The alternating current power-line frequency of 60 Hz was the primary clock rate for the lowest-level operations.
The arithmetic logic functions were fully electronic, implemented with vacuum tubes. The family of logic gates ranged from inverters to two- and three-input gates. The input and output levels and operating voltages were compatible between the different gates. Each gate consisted of one inverting vacuum-tube amplifier, preceded by a resistor divider input network that defined the logical function. The control logic functions, which only needed to operate once per drum rotation and therefore did not require electronic speed, were electromechanical, implemented with relays.
The ALU operated on only one bit of each number at a time; it kept the carry/borrow bit in a capacitor for use in the next AC cycle.John Gustafson.
"Reconstruction of the Atanasoff-Berry Computer".
Quote: "the total vacuum tube count was very low: about 300 for the entire machine. Much of this economy is the result of operating on only one bit of each number at a time, keeping the carry/borrow bit in a capacitor for use in the next cycle."
Although the Atanasoff–Berry computer was an important step up from earlier calculating machines, it was not able to run entirely automatically through an entire problem. An operator was needed to operate the control switches to set up its functions, much like the electro-mechanical calculators and unit record equipment of the time. Selection of the operation to be performed, reading, writing, converting to or from binary to decimal, or reducing a set of equations was made by front-panel switches and, in some cases, jumpers.
There were two forms of input and output: primary user input and output and an intermediate results output and input. The intermediate results storage allowed operation on problems too large to be handled entirely within the electronic memory. (The largest problem that could be solved without the use of the intermediate output and input was two simultaneous equations, a trivial problem.)
Intermediate results were binary, written onto paper sheets by electrostatically modifying the resistance at 1500 locations to represent 30 of the 50-bit numbers (one equation). Each sheet could be written or read in one second. The reliability of the system was limited to about 1 error in 100,000 calculations by these units, primarily attributed to lack of control of the sheets' material characteristics. In retrospect, a solution could have been to add a parity bit to each number as written. This problem was not solved by the time Atanasoff left the university for war-related work.
Primary user input was decimal, via standard IBM 80-column punched cards, and output was decimal, via a front-panel display.
thumb|Inside display on I-35 rest stop 100 north of Des Moines honoring the ABC Computer
thumb|Outside display on I-35 rest stop 100 north of Des Moines honoring the ABC Computer |
Atanasoff–Berry computer | Function | Function
The ABC was designed for a specific purpose the solution of systems of simultaneous linear equations. It could handle systems with up to 29 equations, a difficult problem for the time. Problems of this scale were becoming common in physics, the department in which John Atanasoff worked. The machine could be fed two linear equations with up to 29 variables and a constant term and eliminate one of the variables. This process would be repeated manually for each of the equations, which would result in a system of equations with one fewer variable. Then the whole process would be repeated to eliminate another variable.
George W. Snedecor, the head of Iowa State's Statistics Department, was very likely the first user of an electronic digital computer to solve real-world mathematics problems. He submitted many of these problems to Atanasoff. |
Atanasoff–Berry computer | Patent dispute | Patent dispute
On June 26, 1947, J. Presper Eckert and John Mauchly were the first to file for patent on a digital computing device (ENIAC), much to the surprise of Atanasoff. The ABC had been examined by John Mauchly in June 1941, and Isaac Auerbach, a former student of Mauchly's, alleged that it influenced his later work on ENIAC, although Mauchly denied this. The ENIAC patent did not issue until 1964, and by 1967 Honeywell sued Sperry Rand in an attempt to break the ENIAC patents, arguing that the ABC constituted prior art. The United States District Court for the District of Minnesota released its judgement on October 19, 1973, finding in Honeywell v. Sperry Rand that the ENIAC patent was a derivative of John Atanasoff's invention.
Campbell-Kelly and Aspray conclude:
The case was legally resolved on October 19, 1973, when U.S. District Judge Earl R. Larson held the ENIAC patent invalid, ruling that the ENIAC derived many basic ideas from the Atanasoff–Berry computer. Judge Larson explicitly stated:
Herman Goldstine, one of the original developers of ENIAC wrote:Herman Goldstine, "The Computer from Pascal to von Neumann", 1972; pp. 125–126. |
Atanasoff–Berry computer | Replica | Replica
The original ABC was eventually dismantled in 1948, when the university converted the basement to classrooms, and all of its pieces except for one memory drum were discarded.
In 1997, a team of researchers led by Delwyn Bluhm and John Gustafson from Ames Laboratory (located on the Iowa State University campus) finished building a working replica of the Atanasoff–Berry computer at a cost of $350,000 (equivalent to $ in ). The replica ABC was on display in the first floor lobby of the Durham Center for Computation and Communication at Iowa State University and was subsequently exhibited at the Computer History Museum. |
Atanasoff–Berry computer | See also | See also
History of computing hardware
List of vacuum-tube computers
Mikhail Kravchuk |
Atanasoff–Berry computer | References | References |
Atanasoff–Berry computer | Bibliography | Bibliography
|
Atanasoff–Berry computer | External links | External links
The Birth of the ABC
Reconstruction of the ABC, 1994-1997
John Gustafson, Reconstruction of the Atanasoff-Berry Computer
The ENIAC patent trial
Honeywell v. Sperry Rand Records, 1846-1973, Charles Babbage Institute, University of Minnesota.
The Atanasoff-Berry Computer In Operation (YouTube)
Category:1940s computers
Category:One-of-a-kind computers
Category:Vacuum tube computers
Category:Computer-related introductions in 1942
Category:Early computers
Category:Iowa State University
Category:Serial computers
Category:Paper data storage |
Atanasoff–Berry computer | Table of Content | short description, Overview, Design and construction, Function, Patent dispute, Replica, See also, References, Bibliography, External links |
Andes | Short description | thumb|"Cono de Arita" in the Puna de Atacama, Salta (Argentina)
thumb|Aconcagua
The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long and wide (widest between 18°S and 20°S latitude) and has an average height of about . The Andes extend from south to north through seven South American countries: Argentina, Chile, Bolivia, Peru, Ecuador, Colombia, and Venezuela.
Along their length, the Andes are split into several ranges, separated by intermediate depressions. The Andes are the location of several high plateaus—some of which host major cities such as Quito, Bogotá, Cali, Arequipa, Medellín, Bucaramanga, Sucre, Mérida, El Alto, and La Paz. The Altiplano Plateau is the world's second highest after the Tibetan Plateau. These ranges are in turn grouped into three major divisions based on climate: the Tropical Andes, the Dry Andes, and the Wet Andes.
The Andes are the highest mountain range outside of Asia. The range's highest peak, Argentina's Aconcagua, rises to an elevation of about above sea level. The peak of Chimborazo in the Ecuadorian Andes is farther from the Earth's center than any other location on the Earth's surface, due to the equatorial bulge resulting from the Earth's rotation. The world's highest volcanoes are in the Andes, including Ojos del Salado on the Chile-Argentina border, which rises to .
The Andes are also part of the American Cordillera, a chain of mountain ranges (cordillera) that consists of an almost continuous sequence of mountain ranges that form the western "backbone" of the Americas and Antarctica. |
Andes | Etymology | Etymology
The etymology of the word Andes has been debated. The majority consensus is that it derives from the Quechua word "east"Teofilo Laime Ajacopa, Diccionario Bilingüe Iskay simipi yuyayk'ancha, La Paz, 2007 (Quechua–Spanish dictionary) as in Antisuyu (Quechua for "east region"), one of the four regions of the Inca Empire.
The term cordillera comes from the Spanish word cordel "rope" and is used as a descriptive name for several contiguous sections of the Andes, as well as the entire Andean range, and the combined mountain chain along the western part of the North and South American continents. |
Andes | Geography | Geography
thumb|Aerial view of Valle Carbajal in the Tierra del Fuego. The Andes range is about wide throughout its length, except in the Bolivian flexure where it is about wide.|alt=Mountains with snowy peaks
The Andes can be divided into three sections:
The Southern Andes in Argentina and Chile, south of Llullaillaco,
The Central Andes in Peru and Bolivia, and
The Northern Andes in Venezuela, Colombia, and Ecuador.
At the northern end of the Andes, the separate Sierra Nevada de Santa Marta range is often, but not always, treated as part of the Northern Andes.
The Leeward Antilles islands Aruba, Bonaire, and Curaçao, which lie in the Caribbean Sea off the coast of Venezuela, were formerly thought to represent the submerged peaks of the extreme northern edge of the Andes range, but ongoing geological studies indicate that such a simplification does not do justice to the complex tectonic boundary between the South American and Caribbean plates. |
Andes | Geology | Geology
The Andes are an orogenic belt of mountains along the Pacific Ring of Fire, a zone of volcanic activity that encompasses the Pacific rim of the Americas as well as the Asia-Pacific region. The Andes are the result of tectonic plate processes extending during the Mesozoic and Tertiary eras, caused by the subduction of oceanic crust beneath the South American Plate as the Nazca Plate and South American Plate converge. These processes were accelerated by the effects of climate. As the uplift of the Andes created a rain shadow on the western fringes of Chile, ocean currents and prevailing winds carried moisture away from the Chilean coast. This caused some areas of the subduction zone to be sediment-starved, which in turn prevented the subducting plate from having a well lubricated surface. These factors increased the rate of contractional coastal uplift in the Andes. The main cause of the rise of the Andes is the contraction of the western rim of the South American Plate due to the subduction of the Nazca Plate and the Antarctic Plate. To the east, the Andes range is bounded by several sedimentary basins, such as the Orinoco Basin, the Amazon Basin, the Madre de Dios Basin, and the Gran Chaco, that separate the Andes from the ancient cratons in eastern South America. In the south, the Andes share a long boundary with the former Patagonia Terrane. To the west, the Andes end at the Pacific Ocean, although the Peru-Chile trench can be considered their ultimate western limit. From a geographical approach, the Andes are considered to have their western boundaries marked by the appearance of coastal lowlands and less-rugged topography. The Andes also contain large quantities of iron ore located in many mountains within the range.
The Andean orogen has a series of bends or oroclines. The Bolivian Orocline is a seaward-concave bending in the coast of South America and the Andes Mountains at about 18° S. At this point, the orientation of the Andes turns from northwest in Peru to south in Chile and Argentina. The Andean segments north and south of the Orocline have been rotated 15° counter-clockwise to 20° clockwise respectively. The Bolivian Orocline area overlaps with the area of the maximum width of the Altiplano Plateau, and according to Isacks (1988) the Orocline is related to crustal shortening. The specific point at 18° S where the coastline bends is known as the Arica Elbow. Further south lies the Maipo Orocline, a more subtle orocline between 30° S and 38°S with a seaward-concave break in the trend at 33° S. Near the southern tip of the Andes lies the Patagonian Orocline. |
Andes | Orogeny | Orogeny
The western rim of the South American Plate has been the place of several pre-Andean orogenies since at least the late Proterozoic and early Paleozoic, when several terranes and microcontinents collided and amalgamated with the ancient cratons of eastern South America, by then the South American part of Gondwana.
The formation of the modern Andes began with the events of the Triassic, when Pangaea began the breakup that resulted in developing several rifts. The development continued through the Jurassic Period. It was during the Cretaceous Period that the Andes began to take their present form, by the uplifting, faulting, and folding of sedimentary and metamorphic rocks of the ancient cratons to the east. The rise of the Andes has not been constant, as different regions have had different degrees of tectonic stress, uplift, and erosion.
Across the Drake Passage lie the mountains of the Antarctic Peninsula south of the Scotia Plate, which appear to be a continuation of the Andes chain.
The far east regions of the Andes experience a series of changes resulting from the Andean orogeny. Parts of the Sunsás Orogen in Amazonian craton disappeared from the surface of the earth, being overridden by the Andes. The Sierras de Córdoba, where the effects of the ancient Pampean orogeny can be observed, owe their modern uplift and relief to the Andean orogeny in the Tertiary. Further south in southern Patagonia, the onset of the Andean orogeny caused the Magallanes Basin to evolve from being an extensional back-arc basin in the Mesozoic to being a contractional foreland basin in the Cenozoic. |
Andes | Seismic activity | Seismic activity
Tectonic forces above the subduction zone along the entire west coast of South America where the Nazca Plate and a part of the Antarctic Plate are sliding beneath the South American Plate continue to produce an ongoing orogenic event resulting in minor to major earthquakes and volcanic eruptions to this day. Many high-magnitude earthquakes have been recorded in the region, such as the 2010 Maule earthquake (M8.8), the 2015 Illapel earthquake (M8.2), and the 1960 Valdivia earthquake (M9.5), which as of 2024 was the strongest ever recorded on seismometers.
The amount, magnitude, and type of seismic activity varies greatly along the subduction zone. These differences are due to a wide range of factors, including friction between the plates, angle of subduction, buoyancy of the subducting plate, rate of subduction, and hydration value of the mantle material. The highest rate of seismic activity is observed in the central portion of the boundary, between 33°S and 35°S. In this area, the angle of subduction is very low, meaning the subducting plate is nearly horizontal. Studies of mantle hydration across the subduction zone have shown a correlation between increased material hydration and lower-magnitude, more-frequent seismic activity. Zones exhibiting dehydration instead are thought to have a higher potential for larger, high-magnitude earthquakes in the future.
The mountain range is also a source of shallow intraplate earthquakes within the South American Plate. The largest such earthquake (as of 2024) struck Peru in 1947 and measured 7.5. In the Peruvian Andes, these earthquakes display normal (1946), strike-slip (1976), and reverse (1969, 1983) mechanisms. The Amazonian Craton is actively underthrusted beneath the sub-Andes region of Peru, producing thrust faults. In Colombia, Ecuador, and Peru, thrust faulting occurs along the sub-Andes due in response to contraction brought on by subduction, while in the high Andes, normal faulting occurs in response to gravitational forces.
In the extreme south, a major transform fault separates Tierra del Fuego from the small Scotia Plate. |
Andes | Volcanism | Volcanism
thumb|upright=1.3|Rift Valley near Quilotoa, Ecuador
thumb|upright|This photo from the ISS shows the high plains of the Andes Mountains in the foreground, with a line of young volcanoes facing the much lower Atacama Desert
The Andes range has many active volcanoes distributed in four volcanic zones separated by areas of inactivity. The Andean volcanism is a result of the subduction of the Nazca Plate and Antarctic Plate underneath the South American Plate. The belt is subdivided into four main volcanic zones that are separated from each other by volcanic gaps. The volcanoes of the belt are diverse in terms of activity style, products, and morphology. Although some differences can be explained by which volcanic zone a volcano belongs to, there are significant differences inside volcanic zones and even between neighboring volcanoes. Despite being a typical location for calc-alkalic and subduction volcanism, the Andean Volcanic Belt has a large range of volcano-tectonic settings, such as rift systems, extensional zones, transpressional faults, subduction of mid-ocean ridges, and seamount chains apart from a large range of crustal thicknesses and magma ascent paths, and different amount of crustal assimilations. |
Andes | Ore deposits and evaporites | Ore deposits and evaporites
The Andes Mountains host large ore and salt deposits, and some of their eastern fold and thrust belts act as traps for commercially exploitable amounts of hydrocarbons. In the forelands of the Atacama Desert, some of the largest porphyry copper mineralizations occur, making Chile and Peru the first- and second-largest exporters of copper in the world. Porphyry copper in the western slopes of the Andes has been generated by hydrothermal fluids (mostly water) during the cooling of plutons or volcanic systems. The porphyry mineralization further benefited from the dry climate that reduced the disturbing actions of meteoric water. The dry climate in the central western Andes has also led to the creation of extensive saltpeter deposits that were extensively mined until the invention of synthetic nitrates. Yet another result of the dry climate are the salars of Atacama and Uyuni, the former being the largest source of lithium and the latter the world's largest reserve of the element. Early Mesozoic and Neogene plutonism in Bolivia's Cordillera Central created the Bolivian tin belt as well as the famous, now mostly depleted, silver deposits of Cerro Rico de Potosí. |
Andes | Climate | Climate
The Andes Mountains is connected connection to the climate of South America, particularly through the hyper-arid conditions of the adjacent Atacama Desert. The Atacama Bench, a prominent low-relief feature along the Pacific seaboard, serves as a key geomorphological record of the long-term interplay between Andean tectonics and Cenozoic climate. While the initial uplift and shortening of the Andes were driven by the subduction of the Nazca Plate beneath the South American Plate, arid climate acted as an important feedback mechanism. Reduced erosion rates in the increasingly arid Atacama region may have effectively stopped tectonic activity in certain parts of the mountain range. This lack of erosion could have facilitated the eastward propagation of deformation, leading to the widening of the Andean orogen over time. Thus, the Atacama Desert and its geological features, like the Atacama Bench, offer critical insights into the coupled evolution of the Andes Mountains and the changing regional climate. |
Andes | History | History
The Andes Mountains, initially inhabited by hunter-gatherers, experienced the development of agriculture and the rise of politically centralized civilizations, which culminated in the establishment of the century-long Inca Empire. This all changed in the 16th century, when the Spanish conquistadors colonized the mountains in advance of the mining economy.
In the tide of anti-imperialist nationalism, the Andes became the scene of a series of independence wars in the 19th century, when rebel forces swept through the region to overthrow Spanish colonial rule. Since then, many former Spanish territories have become five independent Andean states. |
Andes | Climate and hydrology | Climate and hydrology
thumb|Central Andes
thumb|Bolivian Andes
The climate in the Andes varies greatly depending on latitude, altitude, and proximity to the sea. Temperature, atmospheric pressure, and humidity decrease in higher elevations. The southern section is rainy and cool, while the central section is dry. The northern Andes are typically rainy and warm, with an average temperature of in Colombia. The climate is known to change drastically in rather short distances. Rainforests exist just kilometers away from the snow-covered peak of Cotopaxi. The mountains have a large effect on the temperatures of nearby areas. The snow line depends on the location. It is between in the tropical Ecuadorian, Colombian, Venezuelan, and northern Peruvian Andes, rising to in the drier mountains of southern Peru and northern Chile south to about 30°S before descending to on Aconcagua at 32°S, at 40°S, at 50°S, and only in Tierra del Fuego at 55°S; from 50°S, several of the larger glaciers descend to sea level.
The Andes of Chile and Argentina can be divided into two climatic and glaciological zones: the Dry Andes and the Wet Andes. Since the Dry Andes extend from the latitudes of the Atacama Desert to the area of the Maule River, precipitation is more sporadic, and there are strong temperature oscillations. The line of equilibrium may shift drastically over short periods of time, leaving a whole glacier in the ablation area or in the accumulation area.
In the high Andes of Central Chile and Mendoza Province, rock glaciers are larger and more common than glaciers; this is due to the high exposure to solar radiation. In these regions, glaciers occur typically at higher altitudes than rock glaciers. The lowest active rock glaciers occur at 900 m a.s.l. in Aconcagua.
Though precipitation increases with height, there are semiarid conditions in the nearly highest mountains of the Andes. This dry steppe climate is considered to be typical of the subtropical position at 32–34° S. The valley bottoms have no woods, just dwarf scrub. The largest glaciers, for example the Plomo Glacier and the Horcones Glaciers, do not even reach in length and have only insignificant ice thickness. At glacial times, however, 20,000 years ago, the glaciers were over ten times longer. On the east side of this section of the Mendozina Andes, they flowed down to and on the west side to about above sea level. The massifs of Aconcagua (), Tupungato (), and Nevado Juncal () are tens of kilometres away from each other and were connected by a joint ice stream network. The Andes' dendritic glacier arms, components of valley glaciers, were up to long and over thick, and spanned a vertical distance of . The climatic glacier snowline (ELA) was lowered from to at glacial times. |
Andes | Flora | Flora
thumb|Laguna de Sonso tropical dry forest in Northern Andes
The Andean region cuts across several natural and floristic regions, due to its extension, from Caribbean Venezuela to cold, windy, and wet Cape Horn passing through the hyperarid Atacama Desert. Rainforests and tropical dry forests used to encircle much of the northern Andes but are now greatly diminished, especially in the Chocó and inter-Andean valleys of Colombia. Opposite the humid Andean slopes are the relatively dry Andean slopes in most of western Peru, Chile, and Argentina. Along with several Interandean Valles, they are typically dominated by deciduous woodland, shrub and xeric vegetation, reaching the extreme in the slopes near the virtually lifeless Atacama Desert.
About 30,000 species of vascular plants live in the Andes, with roughly half being endemic to the region, surpassing the diversity of any other hotspot. The small tree Cinchona pubescens, a source of quinine that is used to treat malaria, is found widely in the Andes as far south as Bolivia. Other important crops that originated from the Andes are tobacco and potatoes. The high-altitude Polylepis forests and woodlands are found in the Andean areas of Colombia, Ecuador, Peru, Bolivia, and Chile. These trees, by locals referred to as Queñua, Yagual, and other names, can be found at altitudes of above sea level. It remains unclear if the patchy distribution of these forests and woodlands is natural, or the result of clearing that began during the Incan period. Regardless, in modern times, the clearance has accelerated, and the trees are now considered highly endangered, with some believing that as little as 10% of the original woodland remains. |
Andes | Fauna | Fauna
thumb|A male Andean cock-of-the-rock, a species found in humid Andean forests and the national bird of Peru
thumb|Herds of alpacas near Ausangate mountain
The Andes are rich in fauna: With almost 1,000 species, of which roughly 2/3 are endemic to the region, the Andes are the most important region in the world for amphibians.Tropical Andes – biodiversityhotspots.org The diversity of animals in the Andes is high, with almost 600 species of mammals (13% endemic), more than 1,700 species of birds (about 1/3 endemic), more than 600 species of reptiles (about 45% endemic), and almost 400 species of fish (about 1/3 endemic).
The vicuña and guanaco can be found living in the Altiplano, while the closely related domesticated llama and alpaca are widely kept by locals as pack animals and for their meat and wool. The crepuscular (active during dawn and dusk) chinchillas, two threatened members of the rodent order, inhabit the Andes' alpine regions.Eisenberg, J.F.; & Redford, K.H. (2000). Mammals of the Neotropics, Volume 3: The Central Neotropics: Ecuador, Peru, Bolivia, Brazil. Eisenberg, J.F.; & Redford, K.H. (1992). Mammals of the Neotropics, Volume 2: The Southern Cone: Chile, Argentina, Uruguay, Paraguay. The Andean condor, the largest bird of its kind in the Western Hemisphere, occurs throughout much of the Andes but generally in very low densities.Fjeldsaa, J.; & Krabbe, N. (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Other animals found in the relatively open habitats of the high Andes include the huemul, cougar, foxes in the genus Pseudalopex, and, for birds, certain species of tinamous (notably members of the genus Nothoprocta), Andean goose, giant coot, flamingos (mainly associated with hypersaline lakes), lesser rhea, Andean flicker, diademed sandpiper-plover, miners, sierra-finches and diuca-finches.
Lake Titicaca hosts several endemics, among them the highly endangered Titicaca flightless grebe and Titicaca water frog.Stuart, Hoffmann, Chanson, Cox, Berridge, Ramani and Young, editors (2008). Threatened Amphibians of the World. A few species of hummingbirds, notably some hillstars, can be seen at altitudes above , but far higher diversities can be found at lower altitudes, especially in the humid Andean forests ("cloud forests") growing on slopes in Colombia, Ecuador, Peru, Bolivia, and far northwestern Argentina. These forest-types, which includes the Yungas and parts of the Chocó, are very rich in flora and fauna, although few large mammals exist, exceptions being the threatened mountain tapir, spectacled bear, and yellow-tailed woolly monkey.
Birds of humid Andean forests include mountain toucans, quetzals, and the Andean cock-of-the-rock, while mixed-species flocks dominated by tanagers and furnariids are commonly seen—in contrast to several vocal but typically cryptic species of wrens, tapaculos, and antpittas.
A number of species such as the royal cinclodes and white-browed tit-spinetail are associated with Polylepis, and consequently also threatened. |
Andes | Human activity | Human activity
The Andes Mountains form a north–south axis of cultural influences. A long series of cultural development culminated in the expansion of the Inca civilization and Inca Empire in the central Andes during the 15th century. The Incas formed this civilization through imperialistic militarism as well as careful and meticulous governmental management.D'Altroy, Terence N. The Incas. Blackwell Publishing, 2003 The government sponsored the construction of aqueducts and roads in addition to pre-existing installations. Some of these constructions still exist today.
thumb|Frederic Edwin Church, Heart of the Andes, 1859.
Devastated by European diseases and by civil war, the Incas were defeated in 1532 by an alliance composed of tens of thousands of allies from nations they had subjugated (e.g. Huancas, Chachapoyas, Cañaris) and a small army of 180 Spaniards led by Francisco Pizarro. One of the few Inca sites the Spanish never found in their conquest was Machu Picchu, which lay hidden on a peak on the eastern edge of the Andes where they descend to the Amazon. The main surviving languages of the Andean peoples are those of the Quechua and Aymara language families. Woodbine Parish and Joseph Barclay Pentland surveyed a large part of the Bolivian Andes from 1826 to 1827. |
Andes | Cities | Cities
In modern times, the largest cities in the Andes are Bogotá, with a metropolitan population of over ten million, and Santiago, Medellín, Cali, and Quito. Lima is a coastal city adjacent to the Andes and is the largest city of all Andean countries. It is the seat of the Andean Community of Nations.
La Paz, Bolivia's seat of government, is the highest capital city in the world, at an elevation of approximately . Parts of the La Paz conurbation, including the city of El Alto, extend up to .
Other cities in or near the Andes include Bariloche, Catamarca, Jujuy, Mendoza, Salta, San Juan, Tucumán, and Ushuaia in Argentina; Calama and Rancagua in Chile; Cochabamba, Oruro, Potosí, Sucre, Tarija, and Yacuiba in Bolivia; Arequipa, Cajamarca, Cusco, Huancayo, Huánuco, Huaraz, Juliaca, and Puno in Peru; Ambato, Cuenca, Ibarra, Latacunga, Loja, Riobamba, and Tulcán in Ecuador; Armenia, Cúcuta, Bucaramanga, Duitama, Ibagué, Ipiales, Manizales, Palmira, Pasto, Pereira, Popayán, Rionegro, Sogamoso, Tunja, and Villavicencio in Colombia; and Barquisimeto, La Grita, Mérida, San Cristóbal, Tovar, Trujillo, and Valera in Venezuela. The cities of Caracas, Valencia, and Maracay are in the Venezuelan Coastal Range, which is a debatable extension of the Andes at the northern extremity of South America. |
Andes | Transportation | Transportation
Cities and large towns are connected with asphalt-paved roads, while smaller towns are often connected by dirt roads, which may require a four-wheel-drive vehicle.
The rough terrain has historically put the costs of building highways and railroads that cross the Andes out of reach of most neighboring countries, even with modern civil engineering practices. For example, the main crossover of the Andes between Argentina and Chile is still accomplished through the Paso Internacional Los Libertadores. Only recently have the ends of some highways that came rather close to one another from the east and the west been connected. Much of the transportation of passengers is done via aircraft.
There is one railroad that connects Chile with Peru via the Andes, however, and there are others that make the same connection via southern Bolivia.
There are multiple highways in Bolivia that cross the Andes. Some of these were built during a period of war between Bolivia and Paraguay, in order to transport Bolivian troops and their supplies to the war front in the lowlands of southeastern Bolivia and western Paraguay.
For decades, Chile claimed ownership of land on the eastern side of the Andes. These claims were given up in about 1870 during the War of the Pacific between Chile and the allied Bolivia and Peru, in a diplomatic deal to keep Peru out of the war. The Chilean Army and Chilean Navy defeated the combined forces of Bolivia and Peru, and Chile took over Bolivia's only province on the Pacific Coast, some land from Peru that was returned to Peru decades later. Bolivia has been completely landlocked ever since. It mostly uses seaports in eastern Argentina and Uruguay for international trade because its diplomatic relations with Chile have been suspended since 1978.
Because of the tortuous terrain in places, villages and towns in the mountains—to which travel via motorized vehicles is of little use—are still located in the high Andes of Chile, Bolivia, Peru, and Ecuador. Locally, the relatives of the camel, the llama, and the alpaca continue to carry out important uses as pack animals, but this use has generally diminished in modern times. Donkeys, mules, and horses are also useful. |
Andes | Agriculture | Agriculture
thumb|Peruvian farmers sowing maize and beans
The ancient peoples of the Andes such as the Incas have practiced irrigation techniques for over 6,000 years. Because of the mountain slopes, terracing has been a common practice. Terracing, however, was only extensively employed after Incan imperial expansions to fuel their expanding realm. The potato holds a very important role as an internally consumed staple crop. Maize was also an important crop for these people, and was used for the production of chicha, important to Andean native people. Currently, tobacco, cotton, and coffee are the main export crops. Coca, despite eradication programs in some countries, remains an important crop for legal local use in a mildly stimulating herbal tea, and illegally for the production of cocaine. |
Andes | Irrigation | Irrigation
thumb|Irrigating land in the Peruvian Andes
In unirrigated land, pasture is the most common type of land use. In the rainy season (summer), part of the rangeland is used for cropping (mainly potatoes, barley, broad beans, and wheat).
Irrigation is helpful in advancing the sowing data of the summer crops, which guarantees an early yield in periods of food shortage. Also, by early sowing, maize can be cultivated higher up in the mountains (up to ). In addition, it makes cropping in the dry season (winter) possible and allows the cultivation of frost-resistant vegetable crops like onion and carrot.W. van Immerzeel, 1989. Irrigation and erosion/flood control at high altitudes in the Andes. Published in Annual Report 1989, pp. 8–24, International Institute for Land Reclamation and Improvement, Wageningen, The Netherlands. On line: |
Andes | Mining | Mining
thumb|left|Chilean huasos, 19th century
The Andes rose to fame for their mineral wealth during the Spanish conquest of South America. Although Andean Amerindian peoples crafted ceremonial jewelry of gold and other metals, the mineralizations of the Andes were first mined on a large scale after the Spanish arrival. Potosí in present-day Bolivia and Cerro de Pasco in Peru were among the principal mines of the Spanish Empire in the New World. Río de la Plata and Argentina derive their names from the silver of Potosí.
Currently, mining in the Andes of Chile and Peru places these countries as the first and second major producers of copper in the world. Peru also contains the 4th-largest goldmine in the world: the Yanacocha. The Bolivian Andes principally produce tin, although historically silver mining had a huge impact on the economy of 17th-century Europe. In Chile in the higher portions of the Andes there are only mining districs dominated by large-scale mining, while medium and small-scale mining is more common at lower altitudes.
There is a long history of mining in the Andes, from the Spanish silver mines in Potosí in the 16th century to the vast current porphyry copper deposits of Chuquicamata and Escondida in Chile and Toquepala in Peru. Other metals, including iron, gold, and tin, in addition to non-metallic resources are important. The Andes have a vast supply of lithium; Argentina, Bolivia, and Chile have the three largest reserves in the world respectively. |
Andes | Peaks | Peaks
This list contains some of the major peaks in the Andes mountain range. The highest peak is Aconcagua of Argentina. |
Andes | Argentina | Argentina
thumb|right|The Aconcagua, Argentina, the highest mountain in the Americas
Aconcagua,
Cerro Bonete,
Galán,
Mercedario,
Pissis, |
Andes | The border between Argentina and Chile | The border between Argentina and Chile
Cerro Bayo,
Cerro Fitz Roy, or 3,405 m, Patagonia, also known as Cerro Chaltén
Cerro Escorial,
Cordón del Azufre,
Falso Azufre,
Incahuasi,
Lastarria,
Llullaillaco,
Maipo,
Marmolejo,
Ojos del Salado,
Olca,
Sierra Nevada de Lagunas Bravas,
Socompa,
Nevado Tres Cruces, (south summit) (III Region)
Tronador,
Tupungato,
Nacimiento,
thumb|Huayna Potosí, Bolivia |
Andes | Bolivia | Bolivia
thumb|Sajama, Bolivia
Janq'u Uma,
Cabaraya,
Chacaltaya,
Chachacomani,
Chaupi Orco,
Huayna Potosí,
Illampu,
Illimani,
Laram Q'awa,
Macizo de Pacuni,
Mururata,
Nevado Anallajsi,
Nevado Charquini,
Nevado Sajama,
Patilla Pata,
Tata Sabaya,
Tunari,
Uturuncu,
Wayna Potosí, |
Andes | Border between Bolivia and Chile | Border between Bolivia and Chile
thumb|Parinacota, Bolivia/Chile
Acotango,
Aucanquilcha,
Michincha,
Iru Phutunqu,
Licancabur,
Olca,
Parinacota,
Paruma,
Pomerape, |
Andes | Chile | Chile
thumb|right|View of Cuernos del Paine in Torres del Paine National Park, Chile
Monte San Valentin,
Cerro Paine Grande,
Cerro Macá, c.
Monte Darwin, c.
Volcan Hudson, c.
Cerro Castillo Dynevor, c.
Mount Tarn, c.
Polleras, c.
Acamarachi, c. |
Andes | Colombia | Colombia
thumb|right|Nevado del Huila, Colombia
Nevado del Huila,
Nevado del Ruiz,
Nevado del Tolima,
Pico Pan de Azúcar,
Ritacuba Negro,
Nevado del Cumbal,
Cerro Negro de Mayasquer,
Ritacuba Blanco,
Nevado del Quindío,
Puracé,
Santa Isabel,
Doña Juana,
Galeras,
Azufral, |
Andes | Ecuador | Ecuador
thumb|right|Chimborazo near Riobamba, Ecuador
Antisana,
Cayambe,
Chiles,
Chimborazo,
Corazón,
Cotopaxi,
El Altar,
Illiniza,
Pichincha,
Quilotoa,
Reventador,
Sangay,
Tungurahua, |
Andes | Peru | Peru
thumb|right|Huandoy, Peru
thumb|right|Alpamayo, Peru
Alpamayo,
Artesonraju,
Carnicero,
Chumpe,
Coropuna,
El Misti,
El Toro,
Huandoy,
Huascarán,
Jirishanca,
Pumasillo,
Rasac,
Rondoy,
Sarapo,
Salcantay,
Seria Norte,
Siula Grande,
Huaytapallana,
Yerupaja,
Yerupaja Chico, |
Andes | Venezuela | Venezuela
thumb|Pico Humboldt at sunset
Pico Bolívar,
Pico Humboldt,
Pico Bonpland,
Pico La Concha,
Pico Piedras Blancas,
Pico El Águila,
Pico El Toro
Pico El León
Pico Mucuñuque |
Andes | See also | See also
Andean Geology—a scientific journal
Andesite line
Apu (god)
Mountain passes of the Andes
List of mountain ranges
Sutter Buttes |
Andes | Notes | Notes |
Andes | References | References
Biggar, J. (2005). The Andes: A Guide For Climbers. 3rd. edition. Andes: Kirkcudbrightshire.
de Roy, T. (2005). The Andes: As the Condor Flies. Firefly books: Richmond Hill.
Fjeldså, J. & N. Krabbe (1990). The Birds of the High Andes. Zoological Museum, University of Copenhagen:
Fjeldså, J. & M. Kessler (1996). Conserving the biological diversity of Polylepis woodlands of the highlands on Peru and Bolivia, a contribution to sustainable natural resource management in the Andes. NORDECO: Copenhagen. |
Andes | Bibliography | Bibliography
|
Andes | External links | External links
University of Arizona: Andes geology
Blueplanetbiomes.org: Climate and animal life of the Andes
Discover-peru.org: Regions and Microclimates in the Andes
Peaklist.org: Complete list of mountains in South America with an elevation at/above
Category:Mountain ranges of South America
*
Category:Regions of South America
Category:Physiographic divisions |
Andes | Table of Content | Short description, Etymology, Geography, Geology, Orogeny, Seismic activity, Volcanism, Ore deposits and evaporites, Climate, History, Climate and hydrology, Flora, Fauna, Human activity, Cities, Transportation, Agriculture, Irrigation, Mining, Peaks, Argentina, The border between Argentina and Chile, Bolivia, Border between Bolivia and Chile, Chile, Colombia, Ecuador, Peru, Venezuela, See also, Notes, References, Bibliography, External links |
Anderida | # | redirect Anderitum |
Anderida | Table of Content | # |
Ancylopoda | Short description | Ancylopoda is a group of browsing, herbivorous, mammals in the Perissodactyla that show long, curved and cleft claws. Morphological evidence indicates the Ancylopoda diverged from the tapirs, rhinoceroses and horses (Euperissodactyla) after the Brontotheria; however, earlier authorities such as Osborn sometimes considered the Ancylopoda to be outside Perissodactyla or, as was popular more recently, to be related to Brontotheriidae.
Macrotherium, which is typically from the middle Miocene of Sansan, in Gers, France, may indicate a distinct genus. Limb-bones resembling those of Macrotherium, but relatively stouter, have been described from the Pliocene beds of Attica and Samos as Ancylotherium. In the Americas, the names Morothorium and Moropus have been applied to similar bones, in the belief that they indicated xenarthrans. Macrotherium magnum must have been an animal of about in length. |
Ancylopoda | References | References
Category:Tapiromorpha
Category:Eocene first appearances
Category:Pleistocene extinctions |
Ancylopoda | Table of Content | Short description, References |
Anchor | short description | thumb|Stockless ship's anchor and chain on display
thumb|Anchor of Amoco Cadiz in Portsall, north-west Brittany, France
thumb|Memorial anchor in Kirjurinluoto, Pori, Finland
thumb|Massive anchor chain for large ships. The weight of the chain is vital for proper holding of the anchor.
An anchor is a device, normally made of metal, used to secure a vessel to the bed of a body of water to prevent the craft from drifting due to wind or current. The word derives from Latin , which itself comes from the Greek ().anchor, Oxford Dictionariesἄγκυρα, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus
Anchors can either be temporary or permanent. Permanent anchors are used in the creation of a mooring, and are rarely moved; a specialist service is normally needed to move or maintain them. Vessels carry one or more temporary anchors, which may be of different designs and weights.
A sea anchor is a drag device, not in contact with the seabed, used to minimize drift of a vessel relative to the water. A drogue is a drag device used to slow or help steer a vessel running before a storm in a following or overtaking sea, or when crossing a bar in a breaking sea. |
Anchor | Anchoring | Anchoring
thumb|Anchor winch, or windlass, on
thumb|Colored plastic inserts on a modern anchor chain show the operator how much chain has been paid out. This knowledge is crucial in all anchoring methods.
thumb|A stockless anchor being broken out
thumb|Holding ground in Akaroa Harbour
Anchors achieve holding power either by "hooking" into the seabed, or weight, or a combination of the two. The weight of the anchor chain can be more than that of the anchor and is critical to proper holding. Permanent moorings use large masses (commonly a block or slab of concrete) resting on the seabed. Semi-permanent mooring anchors (such as mushroom anchors) and large ship's anchors derive a significant portion of their holding power from their weight, while also hooking or embedding in the bottom. Modern anchors for smaller vessels have metal flukes that hook on to rocks on the bottom or bury themselves in soft seabed.
The vessel is attached to the anchor by the rode (also called a cable or a warp). It can be made of rope, chain or a combination of rope and chain. The ratio of the length of rode to the water depth is known as the scope.
Holding ground is the area of sea floor that holds an anchor, and thus the attached ship or boat. Different types of anchor are designed to hold in different types of holding ground. Some bottom materials hold better than others; for instance, hard sand holds well, shell holds poorly. Holding ground may be fouled with obstacles. An anchorage location may be chosen for its holding ground. In poor holding ground, only the weight of an anchor and chain matters; in good holding ground, it is able to dig in, and the holding power can be significantly higher.
The basic anchoring consists of determining the location, dropping the anchor, laying out the scope, setting the hook, and assessing where the vessel ends up. The ship seeks a location that is sufficiently protected; has suitable holding ground, enough depth at low tide and enough room for the boat to swing.
The location to drop the anchor should be approached from down wind or down current, whichever is stronger. As the chosen spot is approached, the vessel should be stopped or even beginning to drift back. The anchor should initially be lowered quickly but under control until it is on the bottom (see anchor windlass). The vessel should continue to drift back, and the cable should be veered out under control (slowly) so it is relatively straight.
Once the desired scope is laid out, the vessel should be gently forced astern, usually using the auxiliary motor but possibly by backing a sail. A hand on the anchor line may telegraph a series of jerks and jolts, indicating the anchor is dragging, or a smooth tension indicative of digging in. As the anchor begins to dig in and resist backward force, the engine may be throttled up to get a thorough set. If the anchor continues to drag, or sets after having dragged too far, it should be retrieved and moved back to the desired position (or another location chosen.) |
Anchor | Using an anchor weight, kellet or sentinel | Using an anchor weight, kellet or sentinel
Lowering a concentrated, heavy weight down the anchor line – rope or chain – directly in front of the bow to the seabed behaves like a heavy chain rode and lowers the angle of pull on the anchor.Hinz, Earl R.; The Complete Book of Anchoring and Mooring, first ed., 1986, Cornell Maritime Press; If the weight is suspended off the seabed it acts as a spring or shock absorber to dampen the sudden actions that are normally transmitted to the anchor and can cause it to dislodge and drag. In light conditions, a kellet reduces the swing of the vessel considerably. In heavier conditions these effects disappear as the rode becomes straightened and the weight ineffective. Known as an "anchor chum weight" or "angel" in the UK. |
Anchor | Forked moor | Forked moor
Using two anchors set approximately 45° apart, or wider angles up to 90°, from the bow is a strong mooring for facing into strong winds. To set anchors in this way, first one anchor is set in the normal fashion. Then, taking in on the first cable as the boat is motored into the wind and letting slack while drifting back, a second anchor is set approximately a half-scope away from the first on a line perpendicular to the wind. After this second anchor is set, the scope on the first is taken up until the vessel is lying between the two anchors and the load is taken equally on each cable.
This moor also to some degree limits the range of a vessel's swing to a narrower oval. Care should be taken that other vessels do not swing down on the boat due to the limited swing range. |
Anchor | Bow and stern | Bow and stern
(Not to be mistaken with the Bahamian moor, below.) In the bow and stern technique, an anchor is set off each the bow and the stern, which can severely limit a vessel's swing range and also align it to steady wind, current or wave conditions. One method of accomplishing this moor is to set a bow anchor normally, then drop back to the limit of the bow cable (or to double the desired scope, e.g. 8:1 if the eventual scope should be 4:1, 10:1 if the eventual scope should be 5:1, etc.) to lower a stern anchor. By taking up on the bow cable the stern anchor can be set. After both anchors are set, tension is taken up on both cables to limit the swing or to align the vessel. |
Anchor | Bahamian moor | Bahamian moor
Similar to the above, a Bahamian moor is used to sharply limit the swing range of a vessel, but allows it to swing to a current. One of the primary characteristics of this technique is the use of a swivel as follows: the first anchor is set normally, and the vessel drops back to the limit of anchor cable. A second anchor is attached to the end of the anchor cable, and is dropped and set. A swivel is attached to the middle of the anchor cable, and the vessel connected to that.
The vessel now swings in the middle of two anchors, which is acceptable in strong reversing currents, but a wind perpendicular to the current may break out the anchors, as they are not aligned for this load. |
Anchor | Backing an anchor | Backing an anchor
Also known as tandem anchoring, in this technique two anchors are deployed in line with each other, on the same rode. With the foremost anchor reducing the load on the aft-most, this technique can develop great holding power and may be appropriate in "ultimate storm" circumstances. It does not limit swinging range, and might not be suitable in some circumstances. There are complications, and the technique requires careful preparation and a level of skill and experience above that required for a single anchor. |
Anchor | Kedging | Kedging
thumb|Statue of Peter the Great in Voronezh, Russia. He is leaning on an anchor, symbolic of his contributions to modernizing and expanding Russia's navy (1860)
Kedging or warping is a technique for moving or turning a ship by using a relatively light anchor.
In yachts, a kedge anchor is an anchor carried in addition to the main, or bower, anchor, and usually stowed aft. Every yacht should carry at least two anchors – the main or bower anchor and a second lighter kedge anchor. It is used occasionally when it is necessary to limit the turning circle as the yacht swings when it is anchored, such as in a narrow river or a deep pool in an otherwise shallow area. Kedge anchors are sometimes used to recover vessels that have run aground.
For ships, a kedge may be dropped while a ship is underway, or carried out in a suitable direction by a tender or ship's boat to enable the ship to be winched off if aground or swung into a particular heading, or even to be held steady against a tidal or other stream.
Historically, it was of particular relevance to sailing warships that used them to outmaneuver opponents when the wind had dropped but might be used by any vessel in confined, shoal water to place it in a more desirable position, provided she had enough manpower. |
Anchor | Club hauling | Club hauling
Club hauling is an archaic technique. When a vessel is in a narrow channel or on a lee shore so that there is no room to tack the vessel in a conventional manner, an anchor attached to the lee quarter may be dropped from the lee bow. This is deployed when the vessel is head to wind and has lost headway. As the vessel gathers sternway the strain on the cable pivots the vessel around what is now the weather quarter turning the vessel onto the other tack. The anchor is then normally cut away (the ship's momentum prevents recovery without aborting the maneuver). Liardet, Francis (1849) Professional Recollections on Points of Seamanship , Discipline, &c.General Principles of Working a Ship, from The New Practical Navigator (1814) . psych.usyd.edu.au |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.