See Also:
Tank
Tank history WW1 WW2
List of tanks WW1, WW2, Modern
US Army List of Tanks WW2 M4_Sherman
US Tank Production World War 2
WW2 German Tank Production Panzer 3 III
Panzer 4 IV Pz4
Tiger 1
King Tiger 2
Maus (Tank) - Panzer VIII WW2 world largest tank
Matilda Infantry Tank
T-34 T34 Soviet medium tank IS-2_Soviet_Tank
ISU-152
T-35 Soviet Heavy Tank,
T-55 Tank,
T-62 Soviet Medium Tank,
T80 Main Battle Tank,
T-90 Main Battle Tank
T-72 Tank
M60 Patton
M1 Abrams M1A1 M1A2

M1 Abrams Main Battle Tank

M1 Abrams Main Battle Tank is the namesake of the late General Creighton Abrams, commander of the 37th Armored Battalion. It is the backbone of the armored forces of the United States military, and several of US allies as well. The purpose of this vehicle is to provide mobile firepower for armored formations and destroy any opposing armored fighting vehicle in the world.

The M1 Abrams was designed by Chrysler Defense (in 1979, General Dynamics Land Systems Division purchased Chrysler Defense Division) and is currently produced by General Dynamics Corporation in Lima, Ohio, and first entered US Army service in 1980.

Production of M1 tanks for the US Army is complete. Over 8,800 M1 and M1A1 tanks have been produced for the US Army and Marine Corps, and the armies of Egypt, Saudi Arabia and Kuwait. Production of new M1A1 and M1A2 Abrams tanks is in its final phase for Foreign Military Sales. Three versions of the Abrams tank are currently in service the original M1 model, dating from the early 1980s, and two newer versions, designated M1A1 and M1A2. The M1A1 series, produced from 1985 through 1993, replaced the M1’s 105mm main gun with a 120mm gun and incorporated numerous other enhancements, including an improved suspension, a new turret, increased armor protection, and a nuclear-chemical-biological protection system. The newer M1A2 series includes all of the M1A1 features plus a commander’s independent thermal viewer, an independent commander’s weapon station, position navigation equipment, and a digital data bus and radio interface unit providing a common picture among M1A2s on the battlefield.

In lieu of new production, the Army is upgrading approximately 1,000 older M1 tanks to the M1A2 configuration. The Army also initiated a modification program for the M1A2 to enhance its digital command and control capabilities and to add the second generation forward looking infrared (FLIR) sights to improve the tank's fightability and lethality during limited visibility. This system enhancement program will be fielded in the 2000 time frame concurrently with the M2A3 Bradley and other advanced digital systems. The initial M1A2 fielding to the First Calvary Division, Ft. Hood, TX, is underway. The Army will continue to field M1A2s to the CONUS contingency corps and other first to fight units into the next decade.

The M1 series tank is equipped with a 1500 horsepower Lycoming Textron gas turbine engine coupled to an Allison hydrokenetic transmission with four forward and two reverse gears. It's tactical crusing range is approximately 275 miles. Despite it's weight, the M1 can attain a top speed of nearly 45 miles per hour. The main armament is a 120mm smooth bore cannon, which replaced the 105mm gun on the initial M1 version. It has day/night fire on the move capability which is provided by a laser range finder, thermal imaging night sight, optical day sight, and a digital ballistic computer. Both the fuel and ammunition are compartmented to enhance survivability. The hull and turret are protected by advanced armor similar to the Chobam armor developed by the British Ministry of Defense. When required, the Abrams may be fitted with "reactive armor" to thwart armor-defeating munitions.

Although fielded in 1980, the Abrams remained untested for over 10 years. When Iraq invaded Kuwait in August 1990, there were concerns that the Abrams would fall victim to the sand and long months of continuous operation without the luxury of peacetime maintenance facilities. There were also doubts about the combat survivability of the extensive turret electronics. Immediately following President Bush's decision to commit US forces to the Gulf region in defense of Kuwait and Saudi Arabia, American armored units began the difficult process of relocating to the threatened area. Due to the shear size and weight of the Abrams, the C-5 Galaxy, the largest cargo aircraft in the US Air Force inventory, was only able to handle one tank at a time. This meant that nearly all of the Abrams tanks deployed in the Gulf War were shipped by cargo ship. Although slow in coming, the arrival of the Abrams was much welcomed by Allied forces, as it is capable of defeating any tank in the Iraqi inventory.


Type: Main battle tank
Place of origin: United States
Specifications
Weight: 63.0 tonnes (69.5 short tons)
Length: 7.92 m (26 ft)
Width: 3.64 m (12 ft)
Height: 2.43 m (8 ft)
Crew: 4 (commander, gunner, loader, driver)
Armour: Chobham,
RHA
Primary armament: 120 mm M256 Smooth Bore Tank Gun
Secondary armament: 1× .50 (12.7 mm) M2 BMG machine gun,
2× M240 7.62 mm machine guns (1 pintle, 1 coaxial)
Engine: AGT-1500 turbine engine,
Renk HSWL 354 transmission
1500 hp (1119 kW)
Power/weight: 24 hp/tonne
Suspension: torsion bar
Operational range: 465 km (288 mi)
Speed: Road: 72 km/h (45 mph)
Off-road: 48 km/h (30 mph)

Armament

Main armament

M-68 A1 Rifled Gun

The M68 (Royal Ordnance L7) is the basic model of Britain's most successful tank gun. The L7 was a 105 mm rifled design intended for use in armored fighting vehicles. It was so successful that it armed not only British post-war designs, but was used almost universally in "the West" as the main armament of almost every main battle tank.

The L7 was developed by Britain's Royal Ordnance Factories to equip British tanks of the postwar (Cold War) period as the successor to the 20 pounder used on Britain's postwar tank - the Centurion.

The L7 was a popular weapon and it was maintained in use even after it was superseded by the L11 series 120 mm rifled tank gun for some Centurion tanks operating as Artillery Forward Observation and AVRE vehicles. The L7, and adaptations of it, can be found today as standard or retrofitted equipment on a wide variety of tanks developed during the Cold War. It is also being used as the main armament of the US Army's Stryker-based Mobile Gun System - M1 Tank.

M-68 A1 Specification

* Caliber: 105 mm
* Weight: 1,282 kg
* Length: 5.89 m
* Rate of fire: 10 rounds per minute (maximum)

Ammunition Available
* APDS
* APERS-T ("Anti-personnel-tracer")
* APFSDS
* Dummy
* HE
* HEAT
* HESH
* Smoke-White phosphorus incendiary
* Target Practice
* Target Practice Discarding Sabot

The main armament of the original model M1 was the M-68 A1 105 mm rifled tank gun firing a variety of HEAT, high explosive, white phosphorus (smoke), and a highly efficient and lethal anti-personnel (multiple flechette) round. This gun is a license-built version of the British Royal Ordnance L7 gun. While a reliable weapon, the 105 mm was becoming obsolete in the face of advances in armor technology, which meant that another tank gun was needed for the M1.


Secondary armament:
The Abrams tank has three machine guns:

1. A .50 cal. (12.7 mm) M2 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 CWS, while the vehicle is buttoned up. On the M1A2, M1A2SEP, the M2 is on a flex mount. With the forthcoming TUSK addon kit the M2, or a Mk 19 grenade launcher, can be mounted on the CROWS remote weapons platform. CROWS is similar to the RWS [(Remote Weapons System)] used on the Stryker family of vehicles.
2. A 7.62 mm (.30 caliber) M240C machine gun in front of the loader's hatch on a skate mount.
3. A 7.62 mm M240C machine gun in a coaxial mount. The coaxial MG is aimed and fired with the computer fire control system used for the main gun.

The turret is fitted with two six-barreled smoke grenade launchers. These can create a thick smoke that blocks both vision and thermal imaging, and can also be armed with chaff. The engine is also equipped with a smoke generator that is triggered by the driver.


M1 Abrams A1 A2 Aiming

The Abrams is equipped with a fire control computer that uses data from a variety of sources, including the Gunner's Primary Sight or "GPS" (thermal or daylight), a laser rangefinder, a wind sensor, a pendulum static cant sensor, and data on the ammunition type. The fire control system uses this data to compute a firing solution for the gunner. Either the commander or gunner can fire the main gun.


M1 Abrams A1 A2 Mobility

The M1 Abrams is powered by a 1500 hp (1119 kW) Honeywell AGT1500 (originally made by Lycoming) gas turbine, and a 6 speed (4 forward, 2 reverse) Allison X-1100-3B Hydro-Kinetic Automatic transmission, giving it a governed top speed of 45 mph (72 km/h) on roads, 30 mph (48 km/h) cross-country. With the engine governor removed, speeds of around 60 mph (100 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. The tank can be fueled with diesel fuel, kerosene, any grade of MOGAS (motor gasoline), or JP-4 or JP-8 jet fuel; the U.S. Army uses JP-8 jet fuel in order to simplify logistics.

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 40 liters of fuel). The high speed, high temperature jet exhaust emitted from the rear of M1 Abrams tanks makes it difficult for the infantry to proceed shadowing the tank in urban combat. The turbine is noisy, comparable to a helicopter engine, although the noise character (pitch) is significantly different from a contemporary diesel tank engine. Future US tanks may return to reciprocating engines for propulsion, as 4-stroke diesel engines have proven quite successful in other modern heavy tanks, e.g. the Leopard 2, Challenger 2 and Merkava. The small size, simplicity, power-to-weight ratio, and easy removal/replacement of the turbine powerpack does, however, present significant advantages over any proposed reciprocating replacement.

M1 Abrams A1 A2 Airborn

The Abrams can be carried by the C-5 Galaxy and C-17 Globemaster III. The limited capacity (one combat-ready tank or two transport-ready tanks in a C-5, one combat-ready tank in a C-17) caused serious logistical problems when deploying the tanks for the First Gulf War, though there was enough time for 1,848 tanks to be transported by ship. Tanks shipped in the transport-ready configuration require depot-level maintenance to install a number of sections of armor, and need to be fueled and loaded with ammunition. Tanks shipped in the combat-ready configuration can enter combat immediately.