The M197 electric cannon is a 20 mm three-barreled electric Gatling-type

rotary cannon A rotary cannon, rotary autocannon, rotary gun or Gatling cannon, is any large-caliber multiple-barreled automatic firearm that uses a Gatling-type rotating barrel assembly to deliver a sustained saturational direct fire at much greater ra ...

used by the

United States military The United States Armed Forces are the Military, military forces of the United States. U.S. United States Code, federal law names six armed forces: the United States Army, Army, United States Marine Corps, Marine Corps, United States Navy, Na ...

Development

The M197 electric cannon was developed primarily for use by

United States Army The United States Army (USA) is the primary Land warfare, land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of th ...

helicopter A helicopter is a type of rotorcraft in which Lift (force), lift and thrust are supplied by horizontally spinning Helicopter rotor, rotors. This allows the helicopter to VTOL, take off and land vertically, to hover (helicopter), hover, and ...

gunship A gunship is a military aircraft armed with heavy aircraft guns, primarily intended for attacking ground targets either as airstrike or as close air support. In modern usage the term "gunship" refers to fixed-wing aircraft having laterally-mo ...

s. Development began in

1967 Events January * January 1 – Canada begins a year-long celebration of the 100th anniversary of Canadian Confederation, Confederation, featuring the Expo 67 World's Fair. * January 6 – Vietnam War: United States Marine Corps and Army of ...

after experience in the

Vietnam War The Vietnam War (1 November 1955 – 30 April 1975) was an armed conflict in Vietnam, Laos, and Cambodia fought between North Vietnam (Democratic Republic of Vietnam) and South Vietnam (Republic of Vietnam) and their allies. North Vietnam w ...

revealed the inadequacy of the 7.62 mm

Minigun The M134 Minigun is an American 7.62×51mm NATO six-barrel rotary machine gun with a high rate of fire (2,000 to 6,000 rounds per minute). It features a Gatling-style rotating barrel assembly with an external power source, normally an elect ...

for gunship use. The M197 is essentially a lightened version of the General Electric M61 Vulcan cannon, with three

barrels A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden staves and bound by wooden or metal hoops. The word vat is often used for large containers for liquids ...

instead of six. Its maximum

rate of fire Rate of fire is the frequency at which a specific weapon can fire or launch its projectiles. This can be influenced by several factors, including operator training level, mechanical limitations, ammunition availability, and weapon condition. In m ...

is one quarter that of the Vulcan, largely to limit its

recoil Recoil (often called knockback, kickback or simply kick) is the rearward thrust generated when a gun is being discharged. In technical terms, the recoil is a result of conservation of momentum, for according to Newton's third law the force requ ...

for light aircraft and helicopter use. It shares the Vulcan's M50 and PGU series 20 mm

ammunition Ammunition, also known as ammo, is the material fired, scattered, dropped, or detonated from any weapon or weapon system. The term includes both expendable weapons (e.g., bombs, missiles, grenades, land mines), and the component parts of oth ...

History

The M197 went into service on later marks of the

AH-1 Cobra The Bell AH-1 Cobra is a single-engined attack helicopter developed and manufactured by the American rotorcraft manufacturer Bell Helicopter. A member of the prolific Huey family, the AH-1 is also referred to as the HueyCobra or Snake. The A ...

, using either the M97 or A/A49E-7 armament subsystems, and was also fitted in a ventral

turret Turret may refer to: * Turret (architecture), a small tower that projects above the wall of a building * Gun turret, a mechanism of a projectile-firing weapon * Optical microscope#Objective turret (revolver or revolving nose piece), Objective turre ...

on the

U.S. Marine Corps The United States Marine Corps (USMC), also referred to as the United States Marines or simply the Marines, is the maritime land force service branch of the United States Department of Defense. It is responsible for conducting expeditionary ...

YOV-10D Bronco NOGS. It is also the basis of the GPU-2/A

gun pod One of the first American attempts at a gun pod was the .50- calibre B-25_Mitchell.html" ;"title="machine gun conformal-mount "blister" pod on the B-25 Mitchell">machine gun conformal-mount "blister" pod on the B-25 Mitchell A gun pod is a det ...

, which incorporates the cannon, a

battery Battery or batterie most often refers to: * Electric battery, a device that provides electrical power * Battery (crime), a crime involving unlawful physical contact Battery may also refer to: Energy source * Battery indicator, a device whic ...

and electric drive

motor An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power gene ...

, and 300 rounds of linkless ammunition. In the Cobra, the weapon is supplied with a

magazine A magazine is a periodical literature, periodical publication, print or digital, produced on a regular schedule, that contains any of a variety of subject-oriented textual and visual content (media), content forms. Magazines are generally fin ...

of 700 linked rounds, with a total capacity including feeder system of 750 rounds. It has a cyclic rate of fire of 730+-50 rounds per minute. Standard practice is to fire the cannon in 30- to 50-round bursts. With extended automatic firing from a hover, the recoil is sufficient that the application of forward cyclic to maintain one's position over the ground is inadequate. The M197 remains in use in the latest AH-1W Cobra and AH-1Z Viper gunships. Although the weapon's rotary drive is theoretically quite reliable, its ammunition feed has been anything but: Marine pilots initially reported an alarmingly high jam rate (sometimes greater than 30%). The USMC and the manufacturer are aware of the problem and in 2011 a linkless feed system developed by Meggit Defense Systems was incorporated into the AH-1W and the Zulus. The system is capable of holding 650 +/-3 rounds in the storage unit with approximately 40 rounds in the feed chute. The M197 is also mounted as a chin turret in Italy's

Agusta A129 Mangusta The Agusta A129 Mangusta () is an attack helicopter originally designed and produced by Italian company Agusta. It is the first attack helicopter to be designed and produced wholly in Europe. It has continued to be developed by AgustaWestland, t ...

CBT helicopter, with a capacity of 500 rounds. The M197 is also mounted as a chin turret in South Korea's

KAI LAH The KAI LAH (Light Armed Helicopter) is a compact twin-engine combat helicopter that is being developed by Korea Aerospace Industries (KAI). The LAH has been developed from the Eurocopter EC155 following an agreement between the multinational man ...

helicopter. Fairchild AU-23A Peacemaker with XM197 20mm cannon

The M197 was also mounted into the AU-23A as a handheld Door gun. The XM301 was an improved M197 intended to be the gun on the later canceled RAH-66 Comanche. The weapon's current contractor is General Dynamics Armament Systems.

Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...

has claimed downing one Iraqi

MiG-21 The Mikoyan-Gurevich MiG-21 (; NATO reporting name: Fishbed) is a supersonic jet aircraft, jet fighter aircraft, fighter and interceptor aircraft, designed by the Mikoyan, Mikoyan-Gurevich OKB, Design Bureau in the Soviet Union. Its nicknames in ...

fighter on 14 February 1986 during the

Iran–Iraq War The Iran–Iraq War, also known as the First Gulf War, was an armed conflict between Iran and Iraq that lasted from September 1980 to August 1988. Active hostilities began with the Iraqi invasion of Iran and lasted for nearly eight years, unti ...

using the M197 gun turret installed on its AH-1J Internationals. The cannon was also used during the "

dogfight A dogfight, or dog fight, is an air combat manoeuvring, aerial battle between fighter aircraft that is conducted at close range. Modern terminology for air-to-air combat is air combat manoeuvring (ACM), which refers to tactical situations requir ...

s" between Iranian AH-1Js and Iraqi helicopters (usually

Mi-24 The Mil Mi-24 (; NATO reporting name: Hind) is a large helicopter gunship, attack helicopter and low-capacity transport helicopter, troop transport with room for eight passengers. It is produced by Mil Moscow Helicopter Plant and was introduced ...

s and

Gazelle A gazelle is one of many antelope species in the genus ''Gazella'' . There are also seven species included in two further genera; '' Eudorcas'' and '' Nanger'', which were formerly considered subgenera of ''Gazella''. A third former subgenus, ' ...

s).

Ammunition

References

External links

GlobalSecurity.org M197

{{DEFAULTSORT:M197 Gatling Gun 20x102mm Aircraft guns Multi-barrel machine guns Rotary cannon United States Marine Corps equipment Military equipment introduced in the 1960s

Development

History

Ammunition

See also

References

External links