M1 Abrams
Overview
 
The M1 Abrams is a third-generation main battle tank
Main battle tank
A main battle tank , also known as a battle tank or universal tank, is a tank that fills the heavy direct fire role of many modern armies. They were originally conceived to replace the light, medium, heavy and super-heavy tanks. Development was spurred onwards in the Cold War with the development...

 produced in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It is named after General
General
A general officer is an officer of high military rank, usually in the army, and in some nations, the air force. The term is widely used by many nations of the world, and when a country uses a different term, there is an equivalent title given....

 Creighton Abrams
Creighton Abrams
Creighton Williams Abrams Jr. was a general in the United States Army who commanded military operations in the Vietnam War from 1968–72 which saw U.S. troop strength in Vietnam fall from a peak of 543,000 to 49,000. He served as Chief of Staff of the United States Army from 1972 until shortly...

, former Army Chief of Staff
Chief of Staff of the United States Army
The Chief of Staff of the Army is a statutory office held by a four-star general in the United States Army, and is the most senior uniformed officer assigned to serve in the Department of the Army, and as such is the principal military advisor and a deputy to the Secretary of the Army; and is in...

 and Commander of US military forces in Vietnam
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

 from 1968 to 1972. The M1 is a well armed, heavily armored, and highly mobile tank designed for modern armored ground warfare
Armoured warfare
Armoured warfare or tank warfare is the use of armoured fighting vehicles in modern warfare. It is a major component of modern methods of war....

. Notable features of the tank include the use of a powerful gas turbine
Gas turbine
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber in-between....

 engine (fueled with JP8 jet fuel), the adoption of sophisticated composite armor, and separate ammunition storage in a blow-out compartment for crew safety.
Encyclopedia
The M1 Abrams is a third-generation main battle tank
Main battle tank
A main battle tank , also known as a battle tank or universal tank, is a tank that fills the heavy direct fire role of many modern armies. They were originally conceived to replace the light, medium, heavy and super-heavy tanks. Development was spurred onwards in the Cold War with the development...

 produced in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It is named after General
General
A general officer is an officer of high military rank, usually in the army, and in some nations, the air force. The term is widely used by many nations of the world, and when a country uses a different term, there is an equivalent title given....

 Creighton Abrams
Creighton Abrams
Creighton Williams Abrams Jr. was a general in the United States Army who commanded military operations in the Vietnam War from 1968–72 which saw U.S. troop strength in Vietnam fall from a peak of 543,000 to 49,000. He served as Chief of Staff of the United States Army from 1972 until shortly...

, former Army Chief of Staff
Chief of Staff of the United States Army
The Chief of Staff of the Army is a statutory office held by a four-star general in the United States Army, and is the most senior uniformed officer assigned to serve in the Department of the Army, and as such is the principal military advisor and a deputy to the Secretary of the Army; and is in...

 and Commander of US military forces in Vietnam
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

 from 1968 to 1972. The M1 is a well armed, heavily armored, and highly mobile tank designed for modern armored ground warfare
Armoured warfare
Armoured warfare or tank warfare is the use of armoured fighting vehicles in modern warfare. It is a major component of modern methods of war....

. Notable features of the tank include the use of a powerful gas turbine
Gas turbine
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber in-between....

 engine (fueled with JP8 jet fuel), the adoption of sophisticated composite armor, and separate ammunition storage in a blow-out compartment for crew safety. With a weight of close to 68 short ton
Short ton
The short ton is a unit of mass equal to . In the United States it is often called simply ton without distinguishing it from the metric ton or the long ton ; rather, the other two are specifically noted. There are, however, some U.S...

s (almost 62 metric tons), it is one of the heaviest main battle tanks currently in service.

The M1 Abrams entered U.S. service in 1980, replacing the M60 tank
M60 Patton
The 105 mm Gun Full Tracked Combat Tank, M60, also known unofficially as the M60 Patton, is a first-generation main battle tank introduced in December 1960. It was widely used by the U.S. and its Cold War allies, especially those in NATO, and remains in service throughout the world today...

. It served for over a decade alongside the improved M60A3, which had entered service in 1978. The M1 remains the principal main battle tank of the United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...

 and Marine Corps
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...

, and the armies of Egypt
Egyptian Army
The Egyptian Army is the largest service branch within the Egyptian Armed Forces and holds power in the current Egyptian government. It is estimated to number around 379,000, in addition to 479,000 reservists for a total of 858,000 strong. The modern army was created in the 1820s, and during the...

, Kuwait
Kuwaiti Army
Kuwaiti Army is the primary land force of the Military of Kuwait.Kuwait's postwar equipment orders include 200 M-84 tanks and eighteen self-propelled 155mm guns from France. Kuwait also has received United States, Russian, and Egyptian armored vehicles...

, Saudi Arabia
Saudi Arabian Army
The Saudi Arabian Army , also called Royal Saudi Land Force . Is a branch of the Saudi Armed Forces. The total number of active troops is estimated to be 233,500The current Chief of the Saudi General Staff is Field Marshal Saleh Al-Muhaya....

, Australia
Australian Army
The Australian Army is Australia's military land force. It is part of the Australian Defence Force along with the Royal Australian Navy and the Royal Australian Air Force. While the Chief of Defence commands the Australian Defence Force , the Army is commanded by the Chief of Army...

, and Iraq
Iraqi Army
The Iraqi Army is the land component of the Iraqi military, active in various forms since being formed by the British during their mandate over the country after World War I....

 in 2010.

Three main versions of the M1 Abrams have been deployed, the M1, M1A1, and M1A2, incorporating improved armament, protection and electronics. These improvements, as well as periodic upgrades to older tanks have allowed this long-serving vehicle to remain in front-line service. The M1A3 is currently under development.

History

The M1 Abrams was developed during the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...

 as a successor to the beleaguered MBT-70. The M1 Abrams contract went to Chrysler Defense and was the first vehicle to adopt Chobham armor. Adaptations prior to the Gulf War
Gulf War
The Persian Gulf War , commonly referred to as simply the Gulf War, was a war waged by a U.N.-authorized coalition force from 34 nations led by the United States, against Iraq in response to Iraq's invasion and annexation of Kuwait.The war is also known under other names, such as the First Gulf...

 (Operations Desert Shield and Desert Storm) gave the vehicle better firepower and NBC protection. Being vastly superior to Iraqi tanks, very few M1 tanks were hit by enemy fire. Upgrades after the war improved the tank's weapons sights and fire control unit. The invasion of Iraq in 2003 destroyed Iraq's military. The subsequent insurgency exposed the tanks' vulnerability to rocket-propelled grenades and mines. These problems were partially rectified with the TUSK kit. The Marine Corps sent a company of M1 Abrams to Afghanistan in late 2010.

Development

The first attempt to replace the aging M60 tank was the MBT-70
MBT-70
The MBT-70 was a 1960s German-U.S. joint project to develop a new main battle tank, which was to be equipped with a number of advanced features. It utilized a newly developed hydropneumatic "kneeling" suspension and housed the entire crew in the large turret...

, developed in partnership with West Germany
West Germany
West Germany is the common English, but not official, name for the Federal Republic of Germany or FRG in the period between its creation in May 1949 to German reunification on 3 October 1990....

 in the 1960s. The MBT-70 was very ambitious, and had various ideas that ultimately proved unsuccessful. As a result of the imminent failure of this project, the U.S. Army introduced the XM803. This succeeded only in producing an expensive system with capabilities similar to the M60.

Congress canceled the MBT-70 in November and XM803 December 1971, and redistributed the funds to the new XM815, later renamed the XM1 Abrams after General Creighton Abrams
Creighton Abrams
Creighton Williams Abrams Jr. was a general in the United States Army who commanded military operations in the Vietnam War from 1968–72 which saw U.S. troop strength in Vietnam fall from a peak of 543,000 to 49,000. He served as Chief of Staff of the United States Army from 1972 until shortly...

. Prototypes were delivered in 1976 by Chrysler Defense and General Motors
General Motors
General Motors Company , commonly known as GM, formerly incorporated as General Motors Corporation, is an American multinational automotive corporation headquartered in Detroit, Michigan and the world's second-largest automaker in 2010...

 armed with the license-built version of the 105 mm Royal Ordnance L7
Royal Ordnance L7
The Royal Ordnance L7 is the basic model of Britain's most successful tank gun. The L7 was a 105 mm L/52 rifled design intended for use in armoured fighting vehicles...

 gun along with a Leopard 2
Leopard 2
The Leopard 2 is a main battle tank developed by Krauss-Maffei in the early 1970s for the West German Army. The tank first entered service in 1979 and succeeded the earlier Leopard 1 as the main battle tank of the German Army. Various versions have served in the armed forces of Germany and twelve...

 for comparison. The turbine-powered Chrysler Defense design was selected for development as the M1; Chrysler had significant experience designing turbine-powered land vehicles going back to the 1950s. In March 1982, General Dynamics
General Dynamics
General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...

 Land Systems Division purchased Chrysler Defense, after Chrysler built over 1,000 M1s.

3,273 M1 Abrams were produced 1979-85 and first entered US Army service in 1980. It was armed with the license-built version of the 105 mm Royal Ordnance L7 gun. An improved model called the M1IP was produced briefly in 1984 and contained small upgrades. The M1IP models were used in the Canadian Army Trophy
Canadian Army Trophy
The Canadian Army Trophy was a tank gunnery competition established to foster excellence, camaraderie and competition among the armoured forces of the NATO countries in Western Europe....

 NATO tank gunnery competition in 1985 and 1987.
About 6,000 M1A1 Abrams were produced from 1986–92 and featured the M256 120 mm (4.7 in) smoothbore
Smoothbore
A smoothbore weapon is one which has a barrel without rifling. Smoothbores range from handheld firearms to powerful tank guns and large artillery mortars.-History of firearms and rifling:...

 cannon
Cannon
A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...

 developed by Rheinmetall AG
Rheinmetall
Rheinmetall AG is a German automotive and defence company with factories in Düsseldorf, Kassel and Unterlüß. The company has a long tradition of making guns and artillery pieces...

 of Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 for the Leopard 2, improved armor, and a CBRN
CBRN
CBRN is an initialism for chemical, biological, radiological, and nuclear. It is used to refer to situations in which any of these four hazards have presented themselves. The term CBRN is a replacement for the cold war term NBC , which had replaced the term ABC that was used in the fifties...

 protection system. Production of M1 and M1A1 tanks totaled some 9,000 tanks at a cost of approximately $4.30 million per unit.

In 1990, Project on Government Oversight
Project on Government Oversight
The Project On Government Oversight , founded in 1981, is an independent non-profit organization in the United States which investigates and seeks to expose corruption and other misconduct. POGO assists whistleblowers and investigates federal agencies, Congress, and government contractors...

 in a report criticized the M1's high costs and low fuel efficiency in comparison with other tanks of similar power and effectiveness such as the Leopard 2. The report was based on data from U.S. Army sources and the Congressional record.

The government-owned Lima Army Tank Plant
Lima Army Tank Plant
The Joint Systems Manufacturing Center, also known as the Lima Army Tank Plant is a tank plant located in Lima, Ohio. It is a Government-Owned, Contractor Operated facility currently operated by General Dynamics Land Systems....

 in Lima, Ohio
Lima, Ohio
Lima is a city in and the county seat of Allen County, Ohio, United States. The municipality is located in northwestern Ohio along Interstate 75 approximately north of Dayton and south-southwest of Toledo....

, currently manufactures the Abrams, the Detroit Arsenal Tank Plant
Detroit Arsenal Tank Plant
The Detroit Arsenal Tank Plant was the first manufacturing plant ever built for the mass production of tanks in the United States. Established in 1940 under Chrysler, this plant was owned by the U.S. government until 1996. It was designed by architect Albert Kahn...

 in Warren, Michigan
Warren, Michigan
Warren is a city in Macomb County in the U.S. state of Michigan. The 2010 census places the city's population at 134,056, making Warren the largest city in Macomb County, the third largest city in Michigan, and Metro Detroit's largest suburb....

 manufactured it from 1982 to 1996. It costs upwards of a tank.

As the Abrams entered service in the 1980s, they operated alongside M60A3 within the United States military, and with other NATO tanks in numerous Cold War exercises. These exercises usually took place in Western Europe, especially West Germany, but also in some other countries, including South Korea. The exercises were aimed at countering Soviet forces. However, by 1991 the USSR had collapsed and the Abrams was instead employed in the Middle East.

Gulf War, 1991

The Abrams remained untested in combat until the Gulf War
Gulf War
The Persian Gulf War , commonly referred to as simply the Gulf War, was a war waged by a U.N.-authorized coalition force from 34 nations led by the United States, against Iraq in response to Iraq's invasion and annexation of Kuwait.The war is also known under other names, such as the First Gulf...

 in 1991 during Operation Desert Storm. A total of 1,848 M1A1s were deployed to Saudi Arabia. The M1A1 was superior to Iraq's Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

-era T-55
T-55
The T-54 and T-55 tanks were a series of main battle tanks designed in the Soviet Union. The first T-54 prototype appeared in March 1945, just before the end of the Second World War. The T-54 entered full production in 1947 and became the main tank for armored units of the Soviet Army, armies of...

 and T-62
T-62
The T-62 is a Soviet main battle tank, a further development of the T-55. Its 115 mm gun was the first smoothbore tank gun in use.The T-62 was produced between 1961 and 1975. It became a standard tank in the Soviet arsenal, partly replacing the T-55, although that tank continued to be...

 tanks, as well as Iraqi-assembled Russian T-72
T-72
The T-72 is a Soviet-designed main battle tank that entered production in 1970. It is developed directly from Obyekt-172, and shares parallel features with the T-64A...

s, and locally-produced copies (Asad Babil tank
Lion of Babylon tank
The Lion of Babylon or Asad Babil was an Iraqi-built version of the Soviet T-72 main battle tank, assembled in a factory established in the 1980s near Taji, north of Baghdad....

). The T-72s, like most Soviet export designs, lacked night vision systems and then-modern rangefinder
Rangefinder
A rangefinder is a device that measures distance from the observer to a target, for the purposes of surveying, determining focus in photography, or accurately aiming a weapon. Some devices use active methods to measure ; others measure distance using trigonometry...

s, though they did have some night fighting tanks with older active infrared systems or floodlights. A total of 23 M1A1s were damaged or destroyed during the war. Some others took minor combat damage, with little effect on their operational readiness. Very few M1 tanks were hit by enemy fire, and there was only one fatality, along with a handful of woundings as a result.
The M1A1 was capable of making kills at ranges in excess of 2500 metres (8,202.1 ft). This range was crucial in combat against previous generation tanks of Soviet design in Desert Storm, as the effective range of the main gun in the Soviet/Iraqi tanks was less than 2000 metres (6,561.7 ft). This meant Abrams tanks could hit Iraqi tanks before the enemy got in range—a decisive advantage in this kind of combat. In friendly fire
Friendly fire
Friendly fire is inadvertent firing towards one's own or otherwise friendly forces while attempting to engage enemy forces, particularly where this results in injury or death. A death resulting from a negligent discharge is not considered friendly fire...

 incidents, the front armor and fore side turret
Gun turret
A gun turret is a weapon mount that protects the crew or mechanism of a projectile-firing weapon and at the same time lets the weapon be aimed and fired in many directions.The turret is also a rotating weapon platform...

 armor survived direct APFSDS
Kinetic energy penetrator
A kinetic energy penetrator is a type of ammunition which, like a bullet, does not contain explosives and uses kinetic energy to penetrate the target....

 hits from other M1A1s. This was not the case for the side armor of the hull and the rear armor of the turret, as both areas were penetrated at least in two occasions by friendly depleted uranium ammunition during the Battle of Norfolk
Battle of Norfolk
The Battle of Norfolk was a tank battle fought on February 27, 1991, during the Persian Gulf War, between armored forces of the United States Army and those of the Ba'athist Iraqi Republican Guard...

.

During Operations Desert Shield
Operation Desert Shield (Iraq)
This article is solely based of 1 article which completely twists and miss-attributes each of the players.al-Qaeda had nothing to do with this and Desert Shield/Storm were US operations.About as accurate as Fox News....

 and Desert Storm some M1A1s were modified with armor upgrades. The M1 can be equipped with mine plow
Mine plow
A mine plow is a tank-mounted device designed to clear a lane through a minefield, allowing other vehicles to follow. Buried land mines are plowed up and pushed outside the tank's track path or tipped over...

 and mine roller
Mine roller
A mine roller or mine trawl is a demining device mounted on a tank or armoured personnel carrier, designed to detonate anti-tank mines. It allows engineers to clear a lane through a minefield which is protected by enemy fire....

 attachments if needed. The M1 chassis also serves as a basis for the Grizzly combat engineering vehicle.

Upgrades

The M1A2 was a further improvement of the M1A1 with a commander's independent thermal viewer, weapon station, position navigation equipment, and a full set of controls and displays linked by a digital data bus. These upgrades also provided the M1A2 with an improved fire control system. The M1A2 System Enhancement Package (SEP) added digital maps, FBCB2
FBCB2
Force XXI Battle Command Brigade and Below is a Linux based communication platform designed for commanders to track friendly and hostile forces on the battlefield. It increases a vehicle commander's situational awareness of the battlefield by gathering information near real-time based on vehicle...

 capabilities, and an improved cooling system to compensate for heat generated by the additional computer systems. The M1A2 SEP also serves as the basis for the M104 Wolverine
M104 Wolverine
The M104 Wolverine Heavy Assault Bridge is an armored combat engineering vehicle designed to provide deployable bridge capability for units engaged in military operations.-Background:...

 heavy assault bridge.

Further upgrades included depleted uranium armor for all variants, a system overhaul that returns all A1s to like-new condition (M1A1 AIM), a digital enhancement package for the A1 (M1A1D), and a commonality program to standardize parts between the U.S. Army and the Marine Corps (M1A1HC).

Iraq War

Further combat was seen during 2003 when US forces invaded Iraq and deposed the Iraqi leader Saddam Hussein
Saddam Hussein
Saddam Hussein Abd al-Majid al-Tikriti was the fifth President of Iraq, serving in this capacity from 16 July 1979 until 9 April 2003...

 in Iraq War during Operation Iraqi Freedom. As of March 2005, approximately 80 Abrams tanks were forced out of action by enemy attacks.

The most lopsided achievement of the M1A1s was the destruction of seven T-72 Lion of Babylon tank
Lion of Babylon tank
The Lion of Babylon or Asad Babil was an Iraqi-built version of the Soviet T-72 main battle tank, assembled in a factory established in the 1980s near Taji, north of Baghdad....

s in a point-blank skirmish (less than 50 yards (45.7 m)) near Mahmoudiyah, about 18 miles (29 km) south of Baghdad, with no losses for the American side. In addition to the Abrams' already heavy armament, some crews were also issued M136 AT4
AT4
The AT4 is an 84-mm unguided, portable, single-shot recoilless smoothbore weapon built in Sweden by Saab Bofors Dynamics...

 shoulder-fired anti-tank weapons under the assumption that they might have to engage heavy armor in tight urban areas where the main gun could not be brought to bear.
Following lessons learned in Desert Storm, the Abrams and many other US combat vehicles used in the conflict were fitted with Combat Identification Panel
Combat Identification Panel
The Combat Identification Panel, also known as the 'Coalition Identification Panel' or simply 'CIP', is a device mounted on military ground vehicles to distinguish them from the enemy during battle. They were developed after the first Gulf War to reduce friendly fire incidents among allied ground...

s to reduce friendly fire incidents. These were fitted on the sides and rear of the turret, with flat panels equipped with a four-cornered 'box' image on either side of the turret front (as seen in the image above). Some Abrams were also fitted with a secondary storage bin on the back of the existing bustle rack
Bustle rack
A bustle rack is a type of storage bin mounted on combat vehicles, usually on the sides and/or rear of the turret. These racks are used to carry extra gear and supplies for the vehicle in the field, as well as give the crew a place to store their belongings so that they don't take up the already...

 on the rear of the turret referred to as a bustle rack extension to enable the crew to carry more supplies and personal belongings.
Several Abrams that were irrecoverable due to loss of mobility or other circumstances were destroyed by friendly forces to prevent their capture, usually by other Abrams, who often found them very difficult to destroy despite their firepower.
Some Abrams were disabled by Iraqi infantrymen in ambush
Ambush
An ambush is a long-established military tactic, in which the aggressors take advantage of concealment and the element of surprise to attack an unsuspecting enemy from concealed positions, such as among dense underbrush or behind hilltops...

es during the invasion. Some troops employed short-range anti-tank rockets and fired at the tracks, rear and top. Other tanks were put out of action when struck in critical places by heavy machine gun rounds. A majority of Abrams damaged post-invasion were by improvised explosive device
Improvised explosive device
An improvised explosive device , also known as a roadside bomb, is a homemade bomb constructed and deployed in ways other than in conventional military action...

s (IEDs).

Due to the vulnerability of tanks in urban combat, the Tank Urban Survival Kit, or TUSK, is being issued to some M1 Abrams. It adds protection in the rear and side of the tank to improve fighting ability in urban environments.

Afghanistan

Operating tanks in Afghanistan can be difficult due to the rough terrain, although Canada and Denmark have deployed Leopard 1 and 2
Leopard 2
The Leopard 2 is a main battle tank developed by Krauss-Maffei in the early 1970s for the West German Army. The tank first entered service in 1979 and succeeded the earlier Leopard 1 as the main battle tank of the German Army. Various versions have served in the armed forces of Germany and twelve...

 battle tanks that have been specifically modified to operate in the relatively flat and arid conditions of south-western Afghanistan. In late 2010 at the request of Regional Command Southwest
Regional Command Southwest
Regional Command is an international military formation, of roughly division size, which is one of the components of the International Security Assistance Force in Afghanistan. It was formed in July 2010 largely from an area previously in Regional Command South. It is headquartered at Camp...

, the US Marine Corps deployed a small detachment of 14 M1A1 Abrams from Delta Company, 1st Tank Battalion
1st Tank Battalion
The 1st Tank Battalion is an armor battalion of the United States Marine Corps which is based out of the Marine Corps Air Ground Combat Center Twentynine Palms, California...

, 1st Marine Division (Forward), to southern Afghanistan in support of operations in Helmand and Kandahar provinces.

Future

The tracked M8 Armored Gun System was conceived as a possible supplement for the Abrams in U.S. service for low-intensity conflict in the early '90s. Prototypes were made but the program was canceled. The 8-wheeled M1128 Mobile Gun System was designed to supplement the Abrams in U.S. service for low-intensity conflict. It has been introduced into service.

The U.S. Army's Future Combat Systems
Future Combat Systems
Future Combat Systems was the United States Army's principal modernization program from 2003 to early 2009. Formally launched in 2003, FCS was envisioned to create new brigades equipped with new manned and unmanned vehicles linked by an unprecedented fast and flexible battlefield network...

' XM1202 Mounted Combat System was to replace the Abrams in U.S. service and was in development when funding for the program was cut from the DoD's
United States Department of Defense
The United States Department of Defense is the U.S...

 budget.

The M1A3 Abrams is in the early design period with the U.S. Army. The Army aims to build prototypes by 2014 and to begin to field the first combat-ready M1A3s by 2018 or 2019.

The M1A2 SEP TUSK Abrams and a modernized M1 Abrams were included in the Ground Combat Vehicle (GCV) Analysis of Alternatives (AOA). Vehicles included in the AOA were determined to be inferior to the planned GCV. The U.S. Army Vice Chief of Staff Gen. Peter Chiarelli commended the M1 Abrams program and recommended a similar approach for the GCV program. The Ground Combat Vehicle family of vehicles is the planned successor to the M1 as well as many other U.S. Army vehicles. However, the Army anticipates that the M1A1 will remain in U.S. service until at least 2021, and the M1A2 to beyond 2050.

Plant shutdown

The U.S. Military is planning to close the Lima Army Tank Plant
Lima Army Tank Plant
The Joint Systems Manufacturing Center, also known as the Lima Army Tank Plant is a tank plant located in Lima, Ohio. It is a Government-Owned, Contractor Operated facility currently operated by General Dynamics Land Systems....

 from 2013 to 2016 in an effort to save over $1 billion; it would be reopened in 2017 to upgrade existing tanks. General Dynamics Land Systems, which operates the factory, opposed the closure, arguing that suspension of operations would increase long-term costs and reduce flexibility. Specifically, they estimate that closing the plant would cost $380 million and restarting production would cost $1.3 billion. If passed, a bill currently in the U.S. Senate would allocate $272 million in funds toward the plant to allow it to continue regular operations through 2013.

Camouflage

Unlike earlier US military vehicles from World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 through Vietnam
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

, which used a scheme of dark brownish green known as "olive drab" with large white stars, prototypes and early production M1 (105 mm gun) & M1-IP models used the flat medium green paint; and the large white insignia stars have transitioned to much smaller black markings. Some units painted their M1s with the older MERDC 4-color paint scheme but the turn-in requirements for these tanks required repainting them to solid green. Therefore, even though a large number of the base model M1s were camouflaged in the field, few or none exist today.

M1A1s came from the factory with the NATO three color camouflage Black/Med-Green/Dark-Brown CARC
Chemical Agent Resistant Coating
Chemical Agent Resistant Coating is the term for the paint commonly applied to military vehicles which provides protection against chemical and biological weapons....

 paint jobs. Today M1A1s are given the NATO three color paint job during rebuilds. M1s and M1A1s deployed to Desert Storm were hastily painted desert tan. Some, but not all, of these tanks were re-painted to their "authorized" paint scheme. M1A2s built for Middle Eastern countries were painted in desert tan. Some M1 series tanks are being painted desert tan for service in Iraq and some are not. Replacement parts (roadwheels, armor skirt panels, drive sprockets, etc.) are painted overall green, which can sometimes lead to vehicles with a patchwork of green and desert tan parts.

Australian M1A1s were desert tan when delivered but have undergone a transition to the Australian Army vehicle standard 'Disruptive Pattern Camouflage'; a scheme that consist of black, olive drab and brown.

Concealment

The turret is fitted with two six-barreled smoke grenade
Smoke grenade
Smoke grenades are canister-type grenades used as ground-to-ground or ground-to-air signaling devices, target or landing zone marking devices, or as screening devices for unit movements. Smoke grenades are normally considered non-lethal, although incorrect use may cause death...

 launchers (USMC M1A1s use an eight-barreled version). These can create a thick smoke that blocks both vision and thermal imaging
Thermography
Infrared thermography, thermal imaging, and thermal video are examples of infrared imaging science. Thermal imaging cameras detect radiation in the infrared range of the electromagnetic spectrum and produce images of that radiation, called thermograms...

. The engine is also equipped with a smoke generator that is triggered by the driver. When activated, fuel is sprayed into the hot turbine exhaust, creating the thick smoke. However, due to change from diesel as a primary fuel to the use of JP-8
JP-8
JP-8, or JP8 is a jet fuel, specified and used widely by the US military. It is specified by MIL-DTL-83133 and British Defence Standard 91-87, and similar to commercial aviation's Jet-A....

, this system is disabled on most Abrams today because of a slightly elevated risk of fire damage to the engine compartment.

Active protection system

In addition to the armor, some Abrams are equipped with a Softkill Active protection system, the AN/VLQ-6 Missile Countermeasure Device (MCD) that can impede the function of guidance systems of some semi-active control line-of-sight (SACLOS
SACLOS
SACLOS is an acronym for Semi-Automatic Command to Line of Sight, a second-generation method of missile guidance. In SACLOS, the operator has to continually point a sighting device at the target while the missile is in flight...

) wire and radio guided anti-tank missiles (such as the Russian AT-3, AT-4, AT-5, AT-6 and the like) and thermally and infrared guided missiles. The MCD works by emitting a massive, condensed infrared signal to confuse the seeker of an anti-tank guided missile
Anti-tank guided missile
An anti-tank missile , anti-tank guided missile , anti-tank guided weapon or anti-armor guided weapon is a guided missile primarily designed to hit and destroy heavily-armored military vehicles....

 (ATGM). However, the drawback to the system is that the ATGM is not destroyed, it is merely directed away from its intended target, leaving the missile to detonate elsewhere. This device is mounted on the turret roof in front of the loader's hatch, and can lead some people to mistake Abrams fitted with these devices for the M1A2 version, since the Commander's Independent Thermal Viewer on the latter is mounted in the same place, though the MCD is box-shaped and fixed in place as opposed to cylindrical and rotating like the CITV.

Armor

The Abrams is protected by armor based on the British-designed Chobham armor
Chobham armour
Chobham armour is the name informally given to a composite armour developed in the 1960s at the British tank research centre on Chobham Common, Surrey, England...

, a further development of the British 'Burlington' armor. Chobham is a composite armor formed by spacing multiple layers of various alloys of steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

, ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...

s, plastic composites, and kevlar
Kevlar
Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires...

, giving an estimated maximum (frontal turret) 1320–1620 mm (52–63.8 ) of RHAe versus HEAT
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

 (and other chemical energy rounds) and 940 millimetre versus kinetic energy penetrators. It may also be fitted with reactive armor over the track skirts if needed (as in the Urban Survival Kit) and slat armor over the rear of the tank and rear fuel cells to protect against ATGMs. Protection against spall
Spall
Spall are flakes of a material that are broken off a larger solid body and can be produced by a variety of mechanisms, including as a result of projectile impact, corrosion, weathering, cavitation, or excessive rolling pressure...

ing is provided by a Kevlar liner. Beginning in 1987, M1A1 tanks received improved armor packages that incorporated depleted uranium (DU) mesh in their armor at the front of the turret and the front of the hull. Armor reinforced in this manner offers significantly increased resistance towards all types of anti-tank weaponry, but at the expense of adding considerable weight to the tank, as depleted uranium is 1.7 times more dense than lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...

.

The first M1A1 tanks to receive this upgrade were tanks stationed in Germany, since they were the first line of defense against the Soviet Union. US-based tank battalions participating in Operation Desert Storm received an emergency program to upgrade their tanks with depleted uranium armor immediately before the onset of the campaign. M1A2 tanks uniformly incorporate depleted uranium armor, and all M1A1 tanks in active service have been upgraded to this standard as well, the added protection from the depleted uranium armor is believed to be equivalent to 24 inches (61 cm) of RHA. In the Gulf War, Abrams tanks survived multiple hits at relatively close ranges from Iraqi Lion of Babylon tanks and ATGMs. M829A1 "Silver Bullet" APFSDS rounds from other M1A1 Abrams were unable to penetrate the front and side armor (even at close ranges) in friendly fire incidents as well as an incident in which an Abrams tried to destroy an abandoned Abrams stuck in the mud.

Damage control

If the Abrams does suffer damage resulting in a fire in the crew compartment, the tank is equipped with a halon
Gaseous fire suppression
Gaseous fire suppression is a term to describe the use of inert gases and chemical agents to extinguish a fire. Also called Clean Agent Fire Suppression. These Agents are governed by the NFPA Standard for Clean Agent Fire Extinguishing Systems - NFPA 2001 in the USA, with different standards and...

 fire-suppression system that automatically engages and extinguishes fires in seconds.

Fuel and ammunition are in armored compartments with blowout panels to protect the crew from the risk of the tank's own ammunition cooking off
Cooking off
Cooking off refers to ammunition exploding prematurely due to heat in the surrounding environment. It can also refer to a technique used when throwing grenades to achieve a controlled, predictable explosion....

 if the tank is damaged.

Primary

M68A1 rifled gun
The main armament of the original model M1 was the M68A1 105 mm rifled
Rifling
Rifling is the process of making helical grooves in the barrel of a gun or firearm, which imparts a spin to a projectile around its long axis...

 tank gun
Tank gun
A tank gun is the main armament of a tank. Modern tank guns are large-caliber high-velocity guns, capable of firing kinetic energy penetrators, high explosive anti-tank rounds, and in some cases guided missiles. Anti-aircraft guns can also be mounted to tanks.-Overview:Tank guns are a specific...

 firing a variety of high explosive anti-tank
High explosive anti-tank
High explosive anti-tank warheads are made of an explosive shaped charge that uses the Munroe effect to create a very high-velocity partial stream of metal in a state of superplasticity that can punch through solid armor....

, high explosive, white phosphorus and an anti-personnel (multiple flechette
Flechette
A flechette is a pointed steel projectile, with a vaned tail for stable flight. The name comes from French , "little arrow" or "dart", and sometimes retains the acute accent in English: fléchette.-Bulk and artillery use:...

) round. This gun is a license-built version of the British Royal Ordnance L7
Royal Ordnance L7
The Royal Ordnance L7 is the basic model of Britain's most successful tank gun. The L7 was a 105 mm L/52 rifled design intended for use in armoured fighting vehicles...

 gun. While being a reliable weapon and widely used by many NATO nations, a cannon with lethality beyond the 3 kilometres (1.9 mi) range was needed to combat newer armor technologies. To attain that lethality, projectile diameter needed to be increased. The M68A1's performance in terms of accuracy and armor-piercing penetration is comparable with the M256A1 up to a 3 kilometres (1.9 mi) range, but beyond that the 105 mm projectile lacks the kinetic energy to defeat modern armor packages. In 1990 all M1 tanks were fitted with 120 mm M256 smooth bore guns thus upgraded to M1A1 standards.

M256 smoothbore gun
The main armament of the M1A1 and M1A2 is the M256A1 120 mm smoothbore gun, designed by Rheinmetall AG of Germany, manufactured under license in the United States by Watervliet Arsenal
Watervliet Arsenal
The Watervliet Arsenal is an arsenal of the United States Army located in Watervliet, New York, on the west bank of the Hudson River. It is the oldest continuously active arsenal in the United States, and today produces much of the artillery for the army, as well as gun tubes for cannons, mortars,...

, New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...

. The M256A1 is a variant of the Rheinmetall 120 mm L/44 gun carried on the German Leopard 2 on all variants up to the Leopard 2A5. Leopard 2A6 replaced the L/44 barrel with a longer L/55.

The M256A1 fires a variety of rounds. The M829A2 APFSDS round was developed specifically to address the improved protection of a Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

n T-72
T-72
The T-72 is a Soviet-designed main battle tank that entered production in 1970. It is developed directly from Obyekt-172, and shares parallel features with the T-64A...

, T-80
T-80
The T-80 is a main battle tank designed and manufactured in the former Soviet Union. A development of the T-64, it entered service in 1976 and was the first production tank to be equipped with a gas turbine engine for main propulsion.the Swedish Stridsvagn 103 of 1971 used a gas turbine alongside...

U or T-90
T-90
The T-90 is a Russian third-generation main battle tank that is a modernisation of the T-72 . It is currently the most modern tank in service with the Russian Ground Forces and Naval Infantry...

 main battle tank equipped with Kontakt-5
Kontakt-5
Kontakt-5 is a type of third-generation explosive reactive armour originating in the Soviet Union. It is the first type of ERA which is effectively able to defeat modern armour-piercing fin-stabilized discarding sabot rounds....

 Explosive Reactive Armor. Later, the M829A3 APFSDS round was introduced to improve its effectiveness against next generation ERA equipped tanks. As a counter to that, the Russian army introduced Relikt
Kontakt-5
Kontakt-5 is a type of third-generation explosive reactive armour originating in the Soviet Union. It is the first type of ERA which is effectively able to defeat modern armour-piercing fin-stabilized discarding sabot rounds....

, the most modern Russian ERA, which is claimed to be twice as effective as Kontakt-5. Development of the M829 series is continuing with the M829E4 currently in development. The Abrams also fires HEAT shaped charge
Shaped charge
A shaped charge is an explosive charge shaped to focus the effect of the explosive's energy. Various types are used to cut and form metal, to initiate nuclear weapons, to penetrate armor, and in the oil and gas industry...

 rounds such as the M830
M830
The M830 is an American high explosive anti-tank round meant primarily for the 120 mm M256 main gun of the M1A1 and M1A2 Abrams. Aside from the double safety, propellant containment bag and M764 fuze, it is identical to the German DM12A1. The cartridge weighs approximately 53.4 lb . The round was...

, the latest version of which (M830A1) incorporates a sophisticated multi-mode electronic sensing fuse
Fuse (explosives)
In an explosive, pyrotechnic device or military munition, a fuse is the part of the device that initiates function. In common usage, the word fuse is used indiscriminately...

 and more fragmentation which allows it to be used effectively against armored vehicles, personnel, and low-flying aircraft. The Abrams uses a manual loader. The fourth tank crew member on the Abrams also provides additional support for maintenance, observation post/listening post (LP/OP) operations, and other tasks.

The new M1028 120 mm anti-personnel canister
Canister shot
Canister shot is a kind of anti-personnel ammunition used in cannons. It was similar to the naval grapeshot, but fired smaller and more numerous balls, which did not have to punch through the wooden hull of a ship...

 cartridge was brought into service early for use in the aftermath of the 2003 invasion of Iraq. It contains 1,098 3/8 in tungsten balls which spread from the muzzle to produce a shotgun
Shotgun
A shotgun is a firearm that is usually designed to be fired from the shoulder, which uses the energy of a fixed shell to fire a number of small spherical pellets called shot, or a solid projectile called a slug...

 effect lethal out to 600 metres (1,968.5 ft). The tungsten balls can be used to clear enemy dismounts, break up hasty ambush sites in urban areas, clear defile
Defile (geography)
Defile is a geographic term for a narrow pass or gorge between mountains or hills. It has its origins as a military description of a pass through which troops can march only in a narrow column or with a narrow front...

s, stop infantry attacks and counter-attacks and support friendly infantry assaults by providing covering fire. The canister round is also a highly effective breaching round and can level cinder block walls and knock man-sized holes in reinforced concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

 walls for infantry
Infantry
Infantrymen are soldiers who are specifically trained for the role of fighting on foot to engage the enemy face to face and have historically borne the brunt of the casualties of combat in wars. As the oldest branch of combat arms, they are the backbone of armies...

 raids at distances up to 75 metres (246.1 ft).

In addition to this, the XM1111 (Mid-Range-Munition Chemical Energy) is also in development. The XM1111 is a guided munition using a dual-mode seeker that combines imaging-infrared and semi-active laser guidance. The MRM-CE was selected over the competing MRM-KE which used a rocket-assisted kinetic energy penetrator. The CE variant was chosen due to its better effects against secondary targets, providing a more versatile weapon. The Army hopes to achieve IOC with the XM1111 by 2013.

Secondary

The Abrams tank has three machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....

s:
  1. A .50 cal.
    Caliber
    In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....

     (12.7 mm
    .50 BMG
    The .50 Browning Machine Gun or 12.7×99mm NATO is a cartridge developed for the Browning .50 caliber machine gun in the late 1910s. Entering service officially in 1921, the round is based on a greatly scaled-up .30-06 cartridge...

    ) M2HB machine gun in front of the commander's hatch. On the M1, M1IP and M1A1, this gun is on a powered mount and can be fired using a 3× magnification sight, known as the Commander's Weapon Station (CWS for short), while the vehicle is "buttoned up" with all its hatches closed to protect the crew. On the M1A2 and M1A2 SEP, this gun is on a flex mount, the commander having to expose himself to fire the weapon manually. With the TUSK add-on kit, an M2HB or a Mk 19 grenade launcher
    Mk 19 grenade launcher
    The Mk 19 Grenade Launcher is a 40 mm belt-fed automatic grenade launcher or grenade machine gun that entered U.S. military service during the Cold War, first seeing action during the Vietnam War and remaining in service today.-Overview:...

     can be mounted on a CROWS remote weapons platform (similar to the Protector M151
    Protector M151
    The M151 PROTECTOR Remote Weapon Station is a remotely-controlled weapons station that can be mounted to vehicles and stationary platforms...

     remote weapon station used on the Stryker
    Stryker
    The IAV Stryker is a family of eight-wheeled, 4-wheel-drive , armored fighting vehicles derived from the Canadian LAV III and produced by General Dynamics Land Systems, in use by the United States Army. The vehicle is named for two American servicemen who posthumously received the Medal of Honor:...

     family of vehicles). However current variants of the TUSK kit on the M1A2 have forgone this, instead adding transparent gun shields to the commander's weapon station. The upgrade variant called M1A1 Abrams Integrated Management (AIM) equips the .50 caliber gun with a thermal sight for accurate night and other low-visibility shooting.
  2. A 7.62 mm
    7.62×51mm NATO
    The 7.62×51mm NATO is a rifle cartridge developed in the 1950s as a standard for small arms among NATO countries...

     M240 machine gun in front of the loader's hatch on a skate mount (seen at right). Some of these have been fitted with gun shield
    Gun shield
    thumb|A [[United States Marine Corps|U.S. Marine]] manning an [[M240 machine gun]] equipped with a gun shieldA gun shield is a flat piece or section of armor designed to be mounted on a crew-served weapon such as a machine gun or artillery piece, or, more rarely, to be used with an assault rifle...

    s during the Iraq War, as well as night-vision scopes for low-visibility engagements.
  3. A second 7.62 mm M240 machine gun in a coaxial mount to the right of the main gun. The coaxial MG is aimed and fired with the same computer fire control system used for the main gun.
  4. (Optional) A second coaxial 12.7 mm M2HB machine gun can be mounted directly above the main gun in a remote weapons platform as part of the TUSK
    Tusk
    Tusks are elongated, continuously growing front teeth, usually but not always in pairs, that protrude well beyond the mouth of certain mammal species. They are most commonly canines, as with warthogs, wild boar, and walruses, or, in the case of elephants and narwhals, elongated incisors...

     upgrade kit.
  5. (Optional) Instead of the .50 cal. coaxial machine gun, an M1 can be fitted with an M134 Minigun
    Minigun
    The Minigun is a 7.62 mm, multi-barrel heavy machine gun with a high rate of fire , employing Gatling-style rotating barrels with an external power source...

     attached to the turret or the roof gun.

Aiming

The Abrams is equipped with a ballistic fire-control computer
Fire-control system
A fire-control system is a number of components working together, usually a gun data computer, a director, and radar, which is designed to assist a weapon system in hitting its target. It performs the same task as a human gunner firing a weapon, but attempts to do so faster and more...

 that uses user and system-supplied data from a variety of sources, to compute, display, and incorporate the three components of a ballistic solution—lead angle, ammunition type, and range to the target—to accurately fire the tank. These three components are determined using a YAG rod laser rangefinder, crosswind sensor, a pendulum
Pendulum
A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced from its resting equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position...

 static cant sensor, data concerning performance and flight characteristics of each specific type of round, tank-specific boresight alignment data, ammunition temperature, air temperature, barometric pressure, a muzzle reference system (MRS) that determines and compensates for barrel droop at the muzzle due to gravitational pull and barrel heating due to firing or sunlight, and target speed determined by tracking rate tachometers in the Gunner's or Commander's Controls Handles. All of these factors are computed into a ballistic solution and updated 30 times per second. The updated solution is displayed in the Gunner's or Tank Commander's field of view in the form of a reticle in both day and Thermal modes. The ballistic computer manipulates the turret and a complex arrangement of mirrors so that all one has to do is keep the reticle on the target and fire to achieve a hit. Proper lead and gun tube elevation are applied to the turret by the computer, greatly simplifying the job of the gunner.

The fire-control system uses these data to compute a firing solution for the gunner. The ballistic solution generated ensures a hit percentage greater than 95 percent at nominal ranges. Either the commander or gunner can fire the main gun. Additionally, the Commander's Independent Thermal Viewer (CITV) on the M1A2 can be used to locate targets and pass them on for the gunner to engage while the commander scans for new targets. In the event of a malfunction or damage to the primary sight system, the main and coaxial weapons can be manually aimed using a telescopic scope boresighted to the main gun known as the Gunner's Auxiliary Sight (GAS). The GAS has two interchangeable reticles
Crosshair
A reticle is a net of fine lines or fibers in the eyepiece of a sighting device, such as a telescope, a telescopic sight, a microscope, or the screen of an oscilloscope. The word reticle comes from the Latin "reticulum," meaning "net." Today, engraved lines or embedded fibers may be replaced by a...

; one for HEAT and MPAT (MultiPurpose AntiTank) rounds and one for APFSDS and STAFF (Smart Target-Activated Fire and Forget) ammunition. Turret traverse and main gun elevation can be accomplished with manual handles and cranks in the event of a Fire Control System or Hydraulic System failure. The commander's M2 .50 caliber machine gun on the M1 and M1A1 is aimed by a 3× magnification sight incorporated into the Commander's Weapon Station (CWS), while the M1A2 uses either the machine gun's own iron sight
Iron sight
Iron sights are a system of shaped alignment markers used as a sighting device to assist in the aiming of a device such as a firearm, crossbow, or telescope, and exclude the use of optics as in telescopic sights or reflector sights...

s, or a remote aiming system such as the CROWS
Common Remotely Operated Weapon System
The Common Remotely Operated Weapon Station program, is a remote weapon station that provides the operator with the ability to acquire and engage targets while inside a vehicle, protected by its armor...

 system when used as part of the TUSK
Tusk
Tusks are elongated, continuously growing front teeth, usually but not always in pairs, that protrude well beyond the mouth of certain mammal species. They are most commonly canines, as with warthogs, wild boar, and walruses, or, in the case of elephants and narwhals, elongated incisors...

 (Tank Urban Survival Kit). The loader's M240 machine gun is aimed either with the built-in iron sights or with a thermal scope mounted on the machine gun.

Tactical

The M1 Abrams is powered by a 1500 shp Honeywell
Honeywell
Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....

 AGT 1500
AGT-1500
The Honeywell AGT1500 gas turbine engine is the main powerplant of the M1 Abrams series of tanks. The engine was originally designed and produced by the Lycoming Turbine Engine Division in the Stratford Army Engine Plant...

 (originally made by Lycoming
Lycoming Engines
Lycoming Engines is a U.S. aircraft engine company, known primarily for its general aviation engines. For most of its history Lycoming has been part of the AVCO group as AVCO Lycoming. In 1987 AVCO was purchased by Textron to become Textron Lycoming...

) multi-fuel turbine, and a six speed (four forward, two reverse) Allison
Allison Transmission
Allison Transmission is an American manufacturer of commercial duty automatic transmissions and hybrid propulsion systems. Allison products are specified by over 250 of the world’s leading vehicle manufacturers and are used in many market sectors including bus, refuse, fire, construction,...

 X-1100-3B Hydro-Kinetic automatic transmission
Automatic transmission
An automatic transmission is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually...

, giving it a governed top speed of 45 mph (72.4 km/h) on paved roads, and 30 mph (48.3 km/h) cross-country. With the engine governor removed, speeds of around 60 mph (96.6 km/h) are possible on an improved surface; however, damage to the drive train (especially to the tracks) and an increased risk of injuries to the crew can occur at speeds above 45 mph (72 km/h). The tank was built around this engine and it is multifuel
Multifuel
Multifuel, sometimes spelled multi-fuel, is a term applied to any type of engine, boiler, or heater or other fuel-burning device which is designed to burn multiple types of fuels in its operation...

 capable; meaning that it can be powered with diesel, kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...

, any grade of motor gasoline
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...

, and jet fuel (such as JP-4
JP-4
JP-4, or JP4 was a jet fuel, specified in 1951 by the U.S. government . It was a 50-50 kerosene-gasoline blend. It has lower flash point than JP-1, but was preferred because of its greater availability. It was the primary U.S. Air Force jet fuel between 1951 and 1995. Its NATO code is F-40...

 or JP-8
JP-8
JP-8, or JP8 is a jet fuel, specified and used widely by the US military. It is specified by MIL-DTL-83133 and British Defence Standard 91-87, and similar to commercial aviation's Jet-A....

). For logistical
Military logistics
Military logistics is the discipline of planning and carrying out the movement and maintenance of military forces. In its most comprehensive sense, it is those aspects or military operations that deal with:...

 reasons, JP-8 is the US military's universal fuel powering both aircraft and vehicle fleets. On the other hand, Australian M1A1 AIM SA are diesel powered since the use of JP-8 is less common in the Australian Army.

Since the Iraq War, the US Army began looking at replacing the AGT-1500 turbine engine in the M1 series because of its fuel usage. The turbine engine provides better acceleration, but takes twice as much fuel as a comparable diesel engine. Turbine engines are lighter than diesels, but take up the extra space and weight in a larger fuel tank to produce the same range. This became a problem in the Persian Gulf War as the speed of a tank division was limited to the speed of its refueling trucks.

The gas turbine propulsion system has proven quite reliable in practice and combat, but its high fuel consumption is a serious logistic issue (starting up the turbine alone consumes nearly 10 gallons (37.9 l) of fuel). The engine burns more than 1.67 gallons (6.3 l) per mile(60 gallons (227.1 l) per hour) when traveling cross-country
and 10 gallons (37.9 l) per hour when idle.
The high speed, high temperature jet blast
Jet blast
Jet blast is the phenomenon of rapid air movement produced by the jet engines of aircraft, particularly on or before takeoff.A large jet-engined aircraft can produce winds of up to 100 mph up to 200 feet behind it at 40% maximum rated power...

 emitted from the rear of M1 Abrams tanks makes it difficult for the infantry to proceed shadowing the tank in urban combat
Urban warfare
Urban warfare is combat conducted in urban areas such as towns and cities. Urban combat is very different from combat in the open at both the operational and tactical level...

. The turbine is very quiet when compared to diesel engines of similar power output and produces a significantly different sound from a contemporary diesel tank engine, reducing the audible distance of the sound, thus earning the Abrams the nickname "whispering death" during its first REFORGER exercise.
Honeywell was developing another gas turbine engine with General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

 for the XM2001 Crusader
XM2001 Crusader
The XM2001 Crusader was to be the United States Army's next-generation self-propelled howitzer , designed to improve survivability, lethality, mobility, and effectiveness and planned to be introduced by 2008. United Defense was the prime contractor; General Dynamics the major subcontractor...

 program that was also to be a replacement for the AGT-1500 engine already in the Abrams tank. The new LV100-5 engine is lighter and smaller (43% fewer parts) with rapid acceleration, quieter running and no visible exhaust. It also features a 33% reduction in fuel consumption (50% less when idle) and near drop-in replacement. The Abrams-Crusader Common Engine Program was shelved when the Crusader program was canceled, however Phase 2 of Army's PROSE (Partnership for Reduced O&S Costs, Engine) program calls for further development of the LV100-5 and replacement of the current AGT-1500 engine.

Using a high power density 330 cc Wankel rotary engine
Wankel engine
The Wankel engine is a type of internal combustion engine using an eccentric rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle takes place in a space between the inside of an oval-like epitrochoid-shaped housing and a rotor that...

 modified to use diesel and military grade jet fuel, TARDEC developed a 220 pounds (99.8 kg) Auxiliary Power Unit
Auxiliary power unit
An auxiliary power unit is a device on a vehicle that provides energy for functions other than propulsion. They are commonly found on large aircraft, as well as some large land vehicles.-Function:...

 designed to fit into the M1 Abrams, replacing an existing battery pack that weighs about 500 pounds (226.8 kg). The new APU will also be more fuel efficient than the tank's main engine. Testing of the first APUs began in 2009.

Although the M1 tank is not designed to carry riders easily, provisions exist for the Abrams to transport troops in tank desant
Tank desant
Tank desant is a military combined arms tactic, where infantry soldiers ride into an attack on tanks, then dismount to fight on foot in the final phase of the assault...

 with the turret stabilization device off. A battle equipped infantry squad
Squad
In military terminology, a squad is a small military unit led by a non-commissioned officer that is subordinate to an infantry platoon. In countries following the British Army tradition this organization is referred to as a section...

 may ride on the rear of the tank, behind the turret. The soldiers can use ropes and equipment straps to provide handholds and snap links to secure themselves. If and when enemy contact is made, the tank conceals itself allowing the infantry to dismount.

Strategic

Strategic mobility is the ability of the tanks of an armed force to arrive in a timely, cost effective, and synchronized fashion. The Abrams can be carried by a C-5 Galaxy
C-5 Galaxy
The Lockheed C-5 Galaxy is a large military transport aircraft built by Lockheed. It provides the United States Air Force with a heavy intercontinental-range strategic airlift capability, one that can carry outsize and oversize cargos, including all air-certifiable cargo. The Galaxy has many...

 or a C-17 Globemaster III
C-17 Globemaster III
The Boeing C-17 Globemaster III is a large military transport aircraft. Developed for the United States Air Force from the 1980s to the early 1990s by McDonnell Douglas, the C-17 is used for rapid strategic airlift of troops and cargo to main operating bases or forward operating bases throughout...

. The limited capacity (two combat-ready in a C-5, one combat-ready tank in a C-17) caused serious logistical problems when deploying the tanks for the first Persian Gulf War, though there was enough time for 1,848 tanks to be transported by ship.

The Abrams is also transportable by truck, namely the M1070 Heavy Equipment Transporter (HET). The HET can operate on highways, secondary roads, and cross-country. The HET accommodates the 4 tank crewmen.

The first instance of the Abrams being airlifted directly into a battlefield occurred in April 2003, when armored elements of the 1st Infantry Division were lifted by C-17s into northern Iraq from Ramstein, Germany to support Task Force Viking
Task Force Viking
Joint Special Operations Task Force – North , also known as Task Force Viking was the command responsible for the northern front during Operation Iraqi Freedom Rotation I...

.

Variants and upgrades

  • XM1: Experimental model. Nine test-beds were produced in 1978.
  • M1: First production variant. Production began (at Chrysler) in 1979 and continued to 1985 (at General Dynamics) (3,273 built for the US).
    • M1IP (Improved Performance): Produced briefly in 1984 before the M1A1, contained upgrades and reconfigurations like new turret with thicker frontal armor, new turret is referred as "long" turret instead of older "short" turret, armor upgraded from ~650mm line of sight thickness to ~880mm (894 build for US).
  • M1A1: Production started in 1985 and continued to 1992, pressurized NBC system, rear bustle rack for improved stowage of supplies and crew belongings, redesigned blow-off panels and M256 120 mm smoothbore cannon (4,976 built for the US Army, 221 for USMC, 755 for Egypt, 59 M1A1 AIM SA sold to Australia).
    • M1A1HA (Heavy Armor): Added 1st generation depleted uranium armor mesh, some tanks were later upgraded with 2nd generation depleted uranium armor mesh, and are unofficially designated M1A1HA+.
    • M1A1HC (Heavy Common): Added new 2nd generation depleted uranium armor mesh, digital engine control and other small upgrades common between Army and Marine Corps tanks.
    • M1A1D (Digital): A digital upgrade for the M1A1HC, to keep up with M1A2SEP, manufactured in quantity for only 2 battalions.
    • M1A1AIM v.1 (Abrams Integrated Management): A program whereby older units are reconditioned to zero hour conditions; and the tank is improved by adding Forward-Looking Infra-Red (FLIR) and Far Target Locate sensors, a tank-infantry phone, communications gear, including FBCB2
      FBCB2
      Force XXI Battle Command Brigade and Below is a Linux based communication platform designed for commanders to track friendly and hostile forces on the battlefield. It increases a vehicle commander's situational awareness of the battlefield by gathering information near real-time based on vehicle...

       and Blue Force Tracking
      Blue Force Tracking
      Blue Force Tracking is a United States military term used to denote a GPS-enabled system that provides military commanders and forces with location information about friendly military forces....

      , to aid in crew situational awareness, and a thermal sight for the .50 caliber machine gun. General Dynamics has been awarded contracts by the US Army to supply this variant.
    • M1A1AIM v.2/M1A1SA (Situational Awareness): Upgrades similar to AIM v.1 tanks + new 3rd generation depleted uranium armor mesh.
    • M1A1FEP (Firepower Enhancement Package): Similar upgrade to AIM v.2 for U.S.M.C. tanks.
    • M1A1KVT (Krasnovian Variant Tank): M1A1s that have been visually modified
      Vismod
      The term vismod is an abbreviation of the term visually modified, and is used by the elements of the United States Department of Defense to refer to any vehicle, aircraft, or other object that has been altered to simulate equipment used by an enemy for training purposes, often by specialized units...

       to resemble Soviet-made tanks for use at the National Training Center, fitted with MILES
      Multiple Integrated Laser Engagement System
      The Multiple Integrated Laser Engagement System or MILES is used by the US military and other armed forces around the world for training purposes. It uses lasers and blank cartridges to simulate actual battle....

       gear and a Hoffman device
      Hoffman tank gunfire simulator
      The Hoffman tank gunfire simulator is a device attached to a tank gun. It is made up of several fluted tubes, which create plumes of smoke, simulating qualities of firing a gun....

      .
    • M1A1M: An export variant ordered by the Iraqi Army
      Iraqi Army
      The Iraqi Army is the land component of the Iraqi military, active in various forms since being formed by the British during their mandate over the country after World War I....

      .

  • M1A2 (Baseline): Production began in 1992 (77 built for the US and more than 600 M1s upgraded to M1A2, 315 for Saudi Arabia, 218 for Kuwait). The M1A2 offers the tank commander an independent thermal sight and ability to, in rapid sequence, shoot at two targets without the need to acquire each one sequentially, also 2nd generation depleted uranium armor mesh.
    • M1A2SEP (System Enhancement Package): Has upgraded 3rd generation depleted uranium armor mesh with graphite coating (240 new built, 300 M1A2s upgraded to M1A2SEP for the USA, also unknown numbers of upgraded basic M1's and M1IP's, also 400 oldest M1A1's upgraded to M1A2SEP).

  • M1A3: Under development, with prospective prototypes by 2014, operational by 2017.

  • M1 TTB (Tank Test Bed): Prototype with unmanned turret, 3 crew members in armored capsule in front of the heavy armored hull, main armament was 120mm smoothbore gun, M256 derivative or modification, mechanical loading system under turret, never fielded.
  • CATTB - Experimental model with a 140 mm smoothbore gun, heavy armored turret and upgraded hull based on the M1's chassis. It had a mechanical loading system in turret bustle, a new engine and probably other upgrades, never fielded. The tank went trials in 1987-1988. CATTB stands for Component Advanced Technology Test Bed.
  • M1 Grizzly Combat Mobility Vehicle (CMV)
  • M1 Panther II Remote Controlled Mine Clearing Vehicle
  • M104 Wolverine
    M104 Wolverine
    The M104 Wolverine Heavy Assault Bridge is an armored combat engineering vehicle designed to provide deployable bridge capability for units engaged in military operations.-Background:...

     Heavy Assault Bridge
  • M1 Panther II Mine Clearing Blade/Roller System.
  • M1ABV Assault Breacher Vehicle
    Assault Breacher Vehicle
    M1 Assault Breacher Vehicle , shortly Breacher, and nicknamed Shredder, is the name of a military vehicle model as first used on a larger scale by the US Marines in the joint ISAF-Afghan Operation Moshtarak in Southern Afghanistan during the War in Afghanistan in 2010 against the Taliban...

    : Assault variant for the USMC. Based upon the M1A1 Abrams chassis, the Assault Breacher Vehicle has a variety of systems installed, such as a full-width mine plow, two linear demolition charges
    Mine-clearing line charge
    A mine-clearing line charge is used to create a breach in minefields under combat conditions. While there are many types, the basic design is for many explosive charges connected on a line to be projected onto the minefield. The charges explode, detonating any buried mines, thus clearing a path...

    , and a lane-marking system. Reactive armor has been fitted to the vehicle providing additional protection against HEAT-based weapons. The turret has been replaced by a new smaller one with two MICLIC launchers at its rear. A M2HB .50 machine gun in a remote weapons station is mounted on the commander's cupola and a bank of grenade launchers are fitted to each side of the superstructure to cover the frontal arc are provided for self-protection.
  • M1 Armored Recovery Vehicle. Only a prototype produced.

Specifications

M1 M1IP M1A1 M1A2 M1A2SEP
Produced 1979–85 1984 1986–92 1992–present
Length 32.04 ft (9.8 m)
Width 12 ft (3.7 m)
Height 7.79 ft (2.4 m) 8 ft (2.4 m)
Top speed 45 mph (20.1 m/s) 41.5 mph (18.6 m/s) 42 mph (18.8 m/s)
Range 310 mi (498.9 km)   288 mi (463.5 km) 243 mi (391.1 km)  
Weight 61.4 short tons (54.8 LT) 62.8 ST (56.1 LT) 67.6 ST (60.4 LT) 68.4 ST (61.1 LT) 69.5 ST (62.1 LT)
Main armament 105 mm M68 rifled
Royal Ordnance L7
The Royal Ordnance L7 is the basic model of Britain's most successful tank gun. The L7 was a 105 mm L/52 rifled design intended for use in armoured fighting vehicles...

120 mm M256 smoothbore
Crew 4 (commander, gunner, loader, driver)


Note: All of the above produce a power of 1500 shp.

Tank Urban Survival Kit

The Tank Urban Survival Kit (TUSK), is a series of improvements to the M1 Abrams intended to improve fighting ability in urban environments. Historically, urban and other close battlefields have been the worst place for tanks to fight—a tank's front armor is much stronger than that on the sides, top, or rear, and in an urban environment, attacks can come from any direction, and attackers can get close enough to reliably hit weak points in the tank's armor, or get sufficient elevation to hit the top armor.

Armor upgrades include reactive armor on the sides of the tank and slat armor
Cage armor
Slat armor is a type of vehicle armor designed to protect against anti-tank rocket-propelled grenade attacks...

 (similar to that on the Stryker
Stryker
The IAV Stryker is a family of eight-wheeled, 4-wheel-drive , armored fighting vehicles derived from the Canadian LAV III and produced by General Dynamics Land Systems, in use by the United States Army. The vehicle is named for two American servicemen who posthumously received the Medal of Honor:...

) on the rear to protect against rocket-propelled grenades and other shaped charge warheads.

A Transparent Armor Gun Shield
Transparent Armor Gun Shield
Built by BAE Systems, the Transparent Armor Gun shield, or TAGS, is a visually transparent protective gun shield for operators of vehicle-mounted machine guns. It borrows on the experience of the Israeli Defense Force in using such armor on a variety of vehicles. The shield is intended to provide...

 and a thermal sight system are added to the loader's top-mounted M240B 7.62 mm machine gun, and a Kongsberg Gruppen
Kongsberg Gruppen
Kongsberg Gruppen is Norway's major defence contractor and maritime automation supplier, located in Kongsberg, a former mining town....

 Remote Weapon Turret carrying a .50 caliber machine gun (again similar to that used on the Stryker) is in place of the tank commander's original .50 caliber machine gun mount, wherein the commander had to expose himself to fire the weapon manually. An exterior telephone
Telephone
The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...

 allows supporting infantry to communicate with the tank commander.

The TUSK system is a field-installable kit that allows tanks to be upgraded without needing to be recalled to a maintenance depot.

While the reactive armor may not be needed in most situations in maneuver warfare
Maneuver warfare
Maneuver warfare, or manoeuvre warfare , is the term used by military theorists for a concept of warfare that advocates attempting to defeat an adversary by incapacitating their decision-making through shock and disruption brought about by movement...

, items like the rear slat armor, loader's gun shield, infantry phone (which saw use on Marine Corps M1A1s as early as 2003), and Kongsberg Remote Weapons Station for the .50 caliber machine gun will be added to the entire M1A2 fleet over time.

On August 29, 2006, General Dynamics Land Systems received a US Army order for 505 Tank Urban Survivability Kits (TUSK) for Abrams main battle tanks supporting operations in Iraq, under a US$45 million contract. The add-on kit will be provided for M1A1 and M1A2-series tanks to enhance crew survivability in urban environments. The kit ordered by the Army consists of a Loader's Armor Gun Shield (LAGS), a Tank Infantry Phone (TIP), Abrams Reactive Armor Tiles (ARAT), a Remote Thermal Sight (RTS) and a Power Distribution Box (PDB). Deliveries are expected to be complete by April 2009.

Under a separate order, the US Army awarded General Dynamics Armament and Technical Products (GDATP) US$30 million to produce reactive armor kits to equip M1A2. The total contract value could reach $59 million if all contract options are exercised. The reactive tiles for the M1 will be locally produced at GDATP's Burlington Technology Center. Tiles will be produced at the company's reactive armor facility in Stone County Operations, McHenry, Miss. On December 8, 2006 the U.S. Army added Counter Improvised Explosive Device enhancements to the M1A1 and M1A2 TUSK, awarding GDLS U.S. $11.3 million, part of the $59 million package mentioned above. In December GDLS also received an order amounting about 40% of a US$48 million order for loader's thermal weapon sights being part of the TUSK system improvements for the M1A1 and M1A2 Abrams Tanks.

Operators

Australian Army
Australian Army
The Australian Army is Australia's military land force. It is part of the Australian Defence Force along with the Royal Australian Navy and the Royal Australian Air Force. While the Chief of Defence commands the Australian Defence Force , the Army is commanded by the Chief of Army...

: 59 M1A1SAs (hybrids with a mix of equipment used by US Army and Marine Corps tanks, without depleted uranium layers in armor) tanks were bought from the United States in 2006, to replace the Leopard AS1 in 2007.
Egyptian Army
Egyptian Army
The Egyptian Army is the largest service branch within the Egyptian Armed Forces and holds power in the current Egyptian government. It is estimated to number around 379,000, in addition to 479,000 reservists for a total of 858,000 strong. The modern army was created in the 1820s, and during the...

: 1,005 M1A1s. Tanks co-produced by the US and Egypt for the Egyptian army. Another 125 Tanks have been ordered.
Iraqi Army
Iraqi Army
The Iraqi Army is the land component of the Iraqi military, active in various forms since being formed by the British during their mandate over the country after World War I....

: 140 M1A1Ms (downgraded, without depleted uranium layers in armor) on order, to be delivered by 2011. Currently 22 US.Army M1A1s are leased for training. The first 11 were delivered to the Iraqi Army in August 2010.
Kuwaiti Army
Kuwaiti Army
Kuwaiti Army is the primary land force of the Military of Kuwait.Kuwait's postwar equipment orders include 200 M-84 tanks and eighteen self-propelled 155mm guns from France. Kuwait also has received United States, Russian, and Egyptian armored vehicles...

: 218 M1A2s (downgraded, without depleted uranium layers in armor)
Saudi Arabian Army
Saudi Arabian Army
The Saudi Arabian Army , also called Royal Saudi Land Force . Is a branch of the Saudi Armed Forces. The total number of active troops is estimated to be 233,500The current Chief of the Saudi General Staff is Field Marshal Saleh Al-Muhaya....

: 373 To be upgraded to M1A2S configuration in Saudi Arabia.
United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...

 and United States Marine Corps
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...

 have approximately 8,725 M1, M1A1 and M1A2 variants combined in inventory.
    • US Army
      • 1,547 M1A2 and M1A2SEP variants (Army inventory)
      • 4,393 M1A1 variants (Army inventory)
      • 2,385 M1 (reserve storage)
    • US Marine Corps
      • 403 M1A1s (Marine Corps inventory)

See also


External links

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