M1-A1 Abrams and M1-A2 Abrams

The M1A2 Abrams is one of, if not the, world's best battle tank. It differs from the M1A1 Abrams in its radar. The M1A1/2 main battle tank's main armament is the M256 120 mm smooth bore gun. The gun may fire M865 TPCSDS-T and M831 TP-T training rounds, the M8300 HEAT-MP-T and the M829 APFSDS-T which includes a depleted uranium penetrator, which has a density 2 1/2 times greater than steel and provides high penetration characteristics. On both sides of the turret, the tank is fitted with six barreled smoke grenade dischargers. A smoke screen can also be laid by an engine operated system. The hull and turret of the M1 are protected by advanced armor and has been battlefield proven. The tanks survived without damage after sustaining direct hits by T-72 tank rounds.

ABRAMS M1A1/2
The M1A1/2 Abrams main battle tank is manufactured by General Dynamics Land Systems (GDLS). The first M1 tank was produced in 1978, the M1A1 in 1985 and the M1A2 in 1986. 3,273 M1 tanks were produced for the US Army. 4,796 M1A1 tanks were built for the US Army, 221 for the US Marines and 555 co-produced with Egypt. 77 M1A2 tanks have been built for the US Army, 315 for Saudi Arabia and 218 for Kuwait. For the M1A2 Upgrade Program, 1079 M1 Abrams tanks are being upgraded to M1A2 configuration.

M1A2 SYSTEM ENHANCEMENT PACKAGE (SEP)
GDLS are contracted to supply 240 M1A2 tanks with a system enhancement package (SEP). The M1A2 SEP will contain an embedded version of the US Army's Force XXI command and control architecture; new Commander's Independent Thermal Viewer; commander's display for digital colour terrain maps; under armour auxiliary power unit; second generation thermal imaging sight with increased range; driver's integrated display and thermal management system. The US Army has plans to procure 1150 M1A2 SEP tanks to be in service by 2004.

ARMAMENT
The main armament is the 120 mm M256 smoothbore gun, developed by Rheinmetall GmbH of Germany. The 120 mm gun fires the following ammunition: the M865 TPCSDS-T and M831 TP-T training rounds, the M8300 HEAT-MP-T and the M829 APFSDS-T which includes a depleted uranium penetrator.
The commander has a 12.7 mm Browning M2 machine gun and the loader has a 7.62 mm M240 machine gun. A 7.62 mm M240 machine gun is also mounted coaxially on the right hand side of the main armament.

SELF-PROTECTION
One L8A1 six-barrelled smoke grenade discharger is fitted on each side of the turret. A smoke screen can also be laid by an engine operated system.
The M1A1 tank incorporates steel encased depleted uranium armour. Armour bulkheads separate the crew compartment from the fuel tanks. The top panels of the tank are designed to blow outwards in the event of penetration by a HEAT projectile. The tank is protected against nuclear, biological and chemical (NBC) warfare.

FIRE CONTROL AND OBSERVATION
The commander's station is equipped with six periscopes, providing 360 degree view. The Raytheon Commander's Independent Thermal Viewer (CITV) provides the commander with independent stabilised day and night vision with a 360 degree view, automatic sector scanning, automatic target cueing of the gunner's sight and back-up fire control.
The M1A2 Abrams tank has a two-axis Raytheon Gunner's Primary Sight- Line of Sight (GPS-LOS) which increases the first round hit probability by providing faster target acquisition and improved gun pointing. The Thermal Imaging System (TIS) has magnification x10 narrow field of view and x3 wide field of view. The thermal image is displayed in the eyepiece of the gunner's sight together with the range measurement from a laser rangefinder. The Litton Laser Systems Eyesafe Laser Rangefinder (ELRF) has a range accuracy to within 10 m and target discrimination of 20 m. The gunner also has a Kollmorgen Model 939 auxiliary sight with magnification x8 and field of view 8 degrees.
The digital fire control computer is supplied by Computing Devices Canada. The fire control computer automatically calculates the fire control solution based on: lead angle measurement; bend of the gun measured by the muzzle reference system; velocity measurement from a wind sensor on the roof of the turret; data from a pendulum static cant sensor located at the centre of the turret roof. The operator manually inputs data on ammunition type, temperature, and barometric pressure.
The driver has either three observation periscopes or two periscopes on either side and a central image intensifying periscope for night vision. The periscopes provide 120 degrees field of view. The Raytheon Driver's Vision Enhancer (DVE), AN/VSS-5, is based on a 328 x 245 element uncooled infrared detector array, operating in the 7.5 to 13 micron waveband. A Raytheon Driver's Thermal Viewer, AN/VAS-3, is installed on the M1A2 Abrams tanks for Kuwait.

PROPULSION
The M1 is equipped with a Lycoming Textron AGT 1500 gas turbine engine. The Allison X-1100-3B transmission provides four forward and two reverse gears. The US Army is considering a new engine for the M1A2, possibly in common with the Crusader self-propelled howitzer, currently being developed.