M1 Abrams

from Wikipedia, the free encyclopedia
M1 Abrams
M1A1 Abrams

M1A1 Abrams

General properties
crew 4 (commander, driver, gunner, loader)
length 9.83 m
width 3.66 m
height 2.86 m
Dimensions 61.3 t
Armament
Main armament 120 mm smoothbore cannon M256
Secondary armament 1 × .50 (12.7 mm) BMG M2 ,
2 × 7.62 mm MGs M240

From TUSK I: 2 × .50 BMG M2 ,
2 × 7.62 mm MGs M240

Protection systems
Armor Chobham - composite armor
Distance-active systems AN / VLQ-6 / 8A (optional)
agility
drive Gas turbine AGT-1500
gearbox Allison DDA X-1100-3B
1119 kW (1500 hp, 1521 PS)
suspension Torsion bar
Top speed 67 km / h
Power / weight 17.8 kW / t (24.2 PS / t)
Range 426 km (on the road)
129 km (off-road)

The M1 Abrams is a main battle tank ( english main battle tank , MBT ) of the United States Army and United States Marine Corps . The M1 replaced the outdated M60 . The first production copy of the M1 was delivered on February 28, 1980. It forms the backbone of the armored forces of the United States , Egypt , Saudi Arabia , Kuwait, and Australia . To date, over 9,000 copies have been built in the USA and Egypt. The M1 was subjected to several combat value increases in order to keep it technologically up to date and to adapt to the threat situation that has changed since its introduction. It is named after the former Chief of Staff of the Army , General Creighton W. Abrams . The unit price for an M1A2 in 1999 was about 6.2 million US dollars . Since 1984, the tank has been equipped with a 120 mm smoothbore cannon manufactured under license from Rheinmetall in the USA .

history

development

The US Army had been using the M60 as the main weapon system of the armored forces since the early 1960s. This model was not a new development, but a vehicle that was "hastily cobbled together from the parts of two previous tanks". James H. Polk, the Commander in Chief of US Forces in Europe, believed that the M60 would "with the best will not be the best tank on the European battlefield". Added to this was the fact that the Warsaw Pact was able to use twice as many tanks as the NATO countries in an attack on the Federal Republic of Germany . Because of this, in 1963, just four years after the M60 went into service, the United States and Germany launched the Kampfpanzer 70 project . Then Defense Secretary Robert McNamara was the project's biggest proponent. He was of the opinion that by sharing ideas and costs, the Allies could not only produce weapons better and cheaper, but they would also be easier and cheaper to maintain than if each nation went its own way. McNamara and the Army, however, had different ideas about the project. McNamara's ideas were politically motivated, while the Army was tactically motivated. McNamara wanted first and foremost to promote cooperation between the nations of the alliance in order to be able to develop new weapons more quickly. The Army, on the other hand, only wanted a new battle tank that was based on the latest technology. Despite the strong support, the program failed after eight years. The main reason was the high unit cost of the new tank. A copy should cost between $ 850,000 and $ 1 million. The US Congress stopped the project after investing about $ 250 million in research and development costs .

An XM1 from the side

In December 1971, shortly after the failure of the Kampfpanzer 70 project, the XM1 Main Battle Tank Program was launched to develop the concept for a new main battle tank to replace the M60. The task force was assigned a budget of $ 217,500 and five months. The task was not to develop a new tank, but only to specify the requirements for the vehicle. The primary questions were:

  • How much should the vehicle weigh?
  • How big should the crew be?
  • How should it be armed?

The condition of Congress in evaluating the properties was that the vehicle should cost a maximum of $ 500,000 each. Much of the evaluation phase was devoted to the weight question. Ultimately, the working group recommended a weight between 46 and 52 t, a crew of four soldiers and a 105-mm main armament. The working group presented its report in August 1972. This was then subjected to another test by the Army in order to eliminate superfluous properties and thus to minimize the costs that had ultimately led to the failure of the Kampfpanzer 70 project. The features that were no longer available included the automatic loading system, the driver's position in the tower and the hydropneumatic chassis. At this point in time, however, there was still disagreement about the level of protection to be achieved. The official upper weight limit for the vehicle at that time was 47.2 t with a high level of protection. These requirements seemed difficult to meet. Many high officers of the armored troops who were involved in the development advocated a reduction in armor and thus in weight in order to maintain the mobility of the vehicle. Others, on the other hand, advocated the high level of protection despite the associated high weight. The final decision on this was made by the later namesake Creighton Abrams, who considered a high level of protection to be the most important property of a main battle tank and at the same time was convinced of the use of Chobham armor . The final concept resulting from these considerations was approved in January 1973 by Deputy Secretary of Defense Bill Clements . The tank was designed to replace the aging M60 fleet and to cope with the assumed threats of 1980. The performance of the M60 should be exceeded in all areas.

An XM1 from the front
Structure description of the M1

As a result, a seven-year development program was started, which was divided into three phases. In phase 1 the prototypes of two companies should be compared. These were, on the one hand, the Chrysler Corporation (now General Dynamics Land Systems), which had already developed the M60, and on the other hand, the Detroit Diesel Allison Division. Both companies should each supply a chassis prototype for driving tests, a turret and a tub for fire tests, as well as a complete copy. The prototypes should be completed in February 1976. Both companies only had the following conditions when developing the prototypes:

  • A maximum weight of 58 t.
  • A maximum width of 3.66 m (144 inches) in order to comply with the European rail loading dimension.
  • Significant improvement in all areas over the M60.
  • The Army's reliability, availability, maintenance, and durability standards should be followed.
  • Maximum unit cost of $ 507,790.

Within these limits, the two companies were able to realize their own ideas regarding protection, mobility and portability in order to meet the requirements.

Shortly after the project was approved, the United States and Germany signed a 1974 Memorandum of Understanding in which it was agreed that the Army should test a prototype of the Leopard 2 . The aim was to achieve the greatest possible standardization between the two vehicles. FMC expressed interest in manufacturing the Leopard 2 for the US Army. The choice of armor was also up for debate. At the beginning of 1974, the USA proposed a change to the Leopard design in order to take over the Burlington composite armor, the existence of which the Federal Republic of Germany had already been informed in March 1970, as the Leopard prototypes were still equipped with perforated armor . In the summer of 1974, the US Army was faced with the choice of either taking over the German armor or holding onto its Burlington , which, however, compared to armored steel did not offer any weight advantage over bullets. In the absence of consensus , General Creighton Abrams decided to use the Burlington . This was further developed by the Ballistic Research Laboratory into " Chobham armor ", which was specially tailored to the needs of the XM1. On the German side, an own composite armor was developed in 1974. As part of the Memorandum of Understanding, the Leopard 2 was also to be tested for its suitability as a new battle tank. During the tests, it was found that this vehicle met or exceeded all Army requirements. Due to the higher weight and the higher price, however, the Leopard 2 was not adopted as a battle tank. Instead, as many assemblies of the two tanks as possible should be identical. Significant changes on the Leopard 2 included the installation of the license-produced laser rangefinder from the US company Hughes , which was cheaper than the EMES 13 and was ready for series production, as well as the use of the WBG basic device from Texas Instruments for the thermal imaging device WBG-X from Zeiss. The XM1 took over the tracks of the Leopard 2 and was to be equipped with the Rheinmetall 120 mm smoothbore cannon in the long term . The technology transfer for this began in 1979.

When developing the first prototypes, Chrysler and General Motors were faced with the challenge of developing an engine that could produce at least twice the output of the old M60, due to the increased weight compared to the M60 and the higher requirements for top speed and acceleration. Chrysler used a modified helicopter gas turbine, while General Motors took a more conventional route and developed a new variable compression diesel engine. The tests with the prototypes were completed in February 1976. The vehicles of both companies met all requirements and had their respective strengths and weaknesses in different areas. In July it was agreed with the British government that the 105mm cannon already used in the M60 should be used. It was noted that the long-term goal of the development was to equip it with a 120 mm cannon. After this first series of tests, one of the two models should be selected; Defense Secretary Donald Rumsfeld urged, however, that the prototype should already be equipped with a 120 mm cannon. Despite protests from the Army, which feared that the project would be discontinued due to the foreseeable delays, both companies began to change their designs accordingly. The turrets were modified to accommodate both the 105mm cannon and the 120mm cannon. Ultimately, it was armed with the 105 mm M68 cannon. The reason for equipping the tank with the inferior weapon in terms of performance was that a proven cannon should be used. Chrysler was awarded the contract for production because the offer for series production was $ 36 million below the offer from General Motors.

Phase 2 of the development program, known as Engineering and Manufacturing Development , began in November 1976. During this phase, Chrysler built eleven pre-production units that were subjected to an intensive test program. At the same time, in addition to the existing factory in Detroit, another tank manufacturing facility was built in Lima, Ohio. This should be able to produce up to 60 tanks a month. Both facilities were owned by the United States but were operated and maintained by Chrysler as the company was most familiar with the manufacturing processes.

M1 Abrams on an Oshkosh M1070

The test series of the pre-production copies suffered from massive problems. The subcontractor for the manufacture of the turbines, Avco Lycoming, was unable to meet the schedule for deliveries of the turbines due to outdated production facilities and poor management, while the turbines that had already been manufactured showed serious quality defects. The resulting failures of the turbines, combined with the low number of pre-series copies, threatened to blow up the tight schedule. As a result, all of the vehicles had to remain in test operation at all times, without Chrysler being able to properly examine and remedy the defects found during the tests. This phase was completed by April 1976, although serious problems with the propulsion system remained. The Army Systems Acquisition Review Council and the Defense Systems Acquisition Review Council then approved the production of a Low Rate Initial Production (LRIP).

M1A1 shortly after being unloaded from a C-17

Plans to install the AGT1500 gas turbine in the Leopard 2 were examined by the company Maschinenbau Kiel (MaK) in 1977 and 1978 on a prototype in Kiel. Due to the advanced stage of development, however, this was discarded for series production because the tub would have had to be changed again.

Transporting tanks by rail
Unloading an M1A1 from an LCAC

In the third phase, another 110 copies were to be produced in both factories in order to carry out further tests on a larger scale. This pre-series was very controversial within the Army, since at that time the reliability and durability of the vehicle left a lot to be desired. The air filters clogged very quickly due to the high air flow, the chains often jumped off the rollers and the soldiers found it difficult to familiarize themselves with the tank due to inadequate operating instructions from the manufacturer. After some suggestions for improvement were implemented by the Army, these problems were partially resolved, but the turbine and the power transmission in particular proved to be very susceptible to failure. The official rollout of the first two copies took place in February 1980 at the Lima Army Tank Plant in Ohio. During this handover ceremony, the tank was named after General Abrams. These two vehicles were subjected to the last technical and tactical troop tests. After the end of the tests, the production of 7058 vehicles was approved in early 1981. At the same time, it was classified as a 105 mm Gun Full Tracked Combat Tank M1 . At the beginning of the series production was only carried out at a rate of 30 units per month in the Lima Army Tank Plant on the instructions of the Defense Minister, since the reliability of the turbine and the power transmission still did not meet the requirements. However, after an expert commission commissioned by the Ministry of Defense gave an optimistic forecast that the existing problems could be remedied by a few modifications, vehicles were also manufactured in the Detroit Army Tank Plant from March 1981, so that production rose to 60 units per month as planned.

To date, over 9,000 copies of the tank have been built, including vehicles for other countries such as Egypt , Saudi Arabia , Kuwait and Australia .

The M1 has been improved several times since its introduction. In 1985 the first major increase in combat value was carried out, so that a new version was created, the M1A1. The M1A1 was first used in the second Gulf War in 1991. Since Operation Desert Storm, in which the M1A1s deployed in 2000 formed the backbone of the Allied forces in Kuwait, all new Abrams have been equipped with special armor made from depleted uranium . The M1A2 is an improved M1A1 with additional infrared vision equipment , GPS and other electronic aids; it has been in production since 1992. In the meantime almost all M1 and M1A1 tanks have been converted to M1A2. A further improvement of the A2 with the name SEP (System Enhancement Program) began in 1999, but was discontinued in the 2004 budget year before the planned 1150 revaluations had taken place. For the M1A1 not subject to the SEP there is another plan to increase combat value, the M1A1-AIM program (Abrams Integrated Management Overhaul Program). Since 2005, two years after the declared end of the Iraq war, some Abrams have been equipped with the Tank Urban Survival Kit (TUSK), which is designed to increase the survivability of the tank during operations in built-up areas.

future

The US Army plans to keep its M1 fleet in operation for a further few years due to the lack of alternatives. The M1A1 is expected to remain in service until 2021, and the M1A2 even beyond 2050. However, the stock is expected to decrease from 8000 vehicles to 2568 units.

The Army considered installing the new 120 mm L / 55 smoothbore cannon from Rheinmetall or the XM291 Advanced Tank Cannon , but this was not implemented, as there could be no threat in the foreseeable future that would not be associated with the L / 44 cannon and the ammunition made from depleted uranium. At one time, the installation of an XM360 variant was also considered in order to standardize the armament with the XM1202 Mounted Combat System .

The Army plans to develop a new version of the M1, the M1A3, from 2014. Parts of the TUSK should be an integral part of the construction in order to further improve the protection of the tank and the crew without drastically increasing the weight. The M256 cannon is to be replaced by a lighter model of a 120 mm cannon. Furthermore, additional rollers are to be attached, the suspension is to be improved and a new, longer-lasting chain is to be used. The armament is to be supplemented by long-range precision systems, which should make it possible to fight targets up to 12 km away. The cabling of the tank is to be replaced by modern fiber optic cabling, which should reduce the total weight by around two tons. The delivery is to take place from 2017. The Marine Corps is faced with the decision to keep the previously existing M1A1 in service, to increase the combat value to the M1A2 SEP version, or to participate in the development of the M1A3.

The Marine Corps is also making its own efforts to further develop the M1, as the tank, unlike the Army models, is not primarily intended to be used against other main battle tanks, but to support infantry. For this purpose, 3000 cartridges of MPAT ammunition were procured to create break-in points for infantrymen in buildings. To protect against RPGs, the introduction of a distance-active protection system is planned, which is intended to destroy approaching projectiles before impact. However, since such protective measures pose a significant threat to the accompanying infantry, there is still resistance within the Marine Corps to their introduction.

crew

As with most western battle tanks, the crew of the M1 consists of four soldiers: the commander, the driver, the gunner and the loader. Seen in the direction of travel, the commander is seated at the rear right in the turret, the gunner in front of him. The loader is located on the left side of the tower. The driver sits in the front of the tank in a semi-recumbent position. The soldiers housed in the tower can get on and off through two hatches in the tower; the driver has his own hatch in the tub.

technology

Armament

An Abrams firing a shot

The armament of the M1 originally consisted of a 105 mm M68 cannon with a rifled barrel, but from 1984 this was replaced by a license production of the 120 mm smooth barrel cannon from Rheinmetall, which is also used in comparable western tanks. The US Army designation for this weapon is M256. The main weapon has a range of 360 ° horizontally and −10 ° to + 20 ° vertically. The weapon and turret are stabilized and are adjusted according to the specifications of the stabilized mirror in the main telescopic sight. The turret is swiveled and the weapon system is aligned using a combined electro-hydraulic drive, but can also be done manually in an emergency. It takes nine seconds to pivot the tower 360 °. The working pressure of the hydraulic system is 105 to 119 bar. To avoid uneven heating in wind or rain, the barrel of the cannon is covered with a heat protection sleeve. A collimator mirror at the mouth of the pipe enables corrections to be made to compensate for distortions in the core axis of the pipe.

M1A1 with an M240 on the left and an M2 on the right

The secondary armament consists of an M240 machine gun (7.62 × 51 mm) mounted axially parallel to the main weapon, another M240 mounted on the loader hatch on a mount and an M48 heavy machine gun (12.7 × 99 mm) on the Commander hatch. The M48 is a modified Browning M2 . The M48 in the M1A1 and M1A2 can be fired both manually and remotely from inside. Commanders of the M1A2 SEP only have the manual option. The swivel range is 360 °, but in practice it is limited by the loader's M240. From version A2 the M48 was replaced by an M2HB ( H eavy B arrel). Furthermore, M250 smoke throw systems with six tubes each are attached to the sides of the tower. These can each shoot three smoke missiles at the same time in order to hide the tank behind a smoke screen. Some M1 were equipped with a new launching system, the designation is M6. In addition to smoke missiles, it can also fire flares to repel heat-seeking missiles. All M1 are also equipped with a vehicle-engine-exhaust smoke system (VEESS), which is supposed to enable fogging through the injection of diesel into the exhaust system. However, since the fuel was switched to JP-8 , the system is no longer functional.

ammunition

Several types of ammunition can be fired from the cannon. All types of ammunition have a partially combustible case. The M829 A4 Armor Piercing Fin - Stabilized Discarding Sabot - Tracer (APFSDS-T) bullet is used against heavily armored targets such as enemy battle tanks . It is a bullet made of depleted uranium . The M865 Target Practice Cone Stabilized Discarding Sabot - Tracer (TPCSDS-T) bullet is used for target practice . It is a practice bullet made of steel, which is stabilized by a perforated cone tail instead of wings. For the first few kilometers of the flight path, the bullet has almost the same trajectory as the M829, but the safety area is greatly reduced.

Loader with cartridge

The M830 and M830A1 HEAT-MP-T High Explosive Anti Tank Multi Purpose - Tracer (HEAT-MP-T) are used against weakly armored and soft targets as well as field fortifications . Despite the similar name, the M830A1 is not a further development of the M830, but a completely new development. The M830 bullet has a muzzle velocity of 1140 m / s and weighs about 24.2 kg. The detonator of the projectile is activated after a flight distance of 30 m; at this distance, the bullet acts only through its impact. It is preferably used in combat in urban areas to fight opponents behind cover and inside buildings. The M830A1 projectile has an adjustable fuse that allows detonation on impact or on approach. The approach detonation is used to combat slow-flying aircraft. In contrast to the M830, the M830A1 has a sabot . Use in urban areas is therefore restricted because the detached parts of the sabot may cause collateral damage. The M830A1 has a muzzle velocity of 1410 m / s and weighs about 22.7 kg. To distinguish the loader, the M830 is called HEAT , the M830A1 as MPAT .

Structure of an M829 cartridge

In order to be able to fight infantry effectively, the M1028 grapple was developed from August 2002 , which contains 1100 tungsten balls and thus acts like shotgun ammunition . The approximately 9.5 mm large tungsten balls are housed in a container that breaks open after leaving the tube and releases the balls, which then spread out in a cone shape. Combat targets behind walls and remove light roadblocks is also possible. The effective range is about 500 m. Another new development is the M908 High Explosive - Obstacle Reducing - Tracer (HE-OR-T), which is supposed to make it possible to remove roadblocks without the aid of engineer tanks . The projectile is a modified M830A1 shaped charge projectile, which is equipped with a steel tip and a delay fuse to penetrate deep into an obstacle and then detonate inside.

The ammunition is stored in an ammunition magazine in the rear of the tank, which is separated from the fighting compartment by a hydraulically operated bulkhead. During the reloading process, the loader operates a switch with his knee that opens the bulkhead. After removing the appropriate type of ammunition, the loader releases the switch and the bulkhead closes again. According to the US Army regulations, the bulkhead may only be opened when the breech of the cannon is fully open. During a firing process, unburned residues of the propellant charge can re-ignite and penetrate into the fighting compartment (called "flashback" in Army jargon) due to the sudden contact with oxygen flowing in through the opening bolt. If the bulkhead is open during such a flashback, it can ignite the combustible case of the ammunition and thus ignite the projectile in the fighting compartment, which would lead to the death of the crew. The top of the ammunition magazine is provided with predetermined breaking points in order to divert the energy upwards in the event of an ammunition explosion and to enable the crew to survive.

Armor and protection systems

The M1 is protected by composite armor, most commonly referred to as Chobham armor . In addition to the outer protective cover, the fuel tanks and the ammunition depot are housed in their own armored areas in order to reduce the risk of a fuel fire or an ammunition explosion. The ammunition bunker in the rear of the tower also has blow-out panels on the upper side in order to divert the energy of an explosion of the ammunition stored there to the outside. The interior of the tank is lined with Kevlar mats from version M1A1 onwards, in order to reduce or completely prevent the splinter cone when penetrating the armor. An automatic fire extinguishing system is installed in the combat and engine room to protect against fire. This detects fire by means of optical sensors within 100 milliseconds and extinguishes it with Halon . Starting with version M1A1, an NBC protection system, a radiation measuring device of the type AN / VDR-1 and a sensor for chemical weapons were installed.

The Chobham armor was supplemented with a layer of depleted uranium in later versions

The outer protective cover consists mainly of armor steel according to MIL-A-11356. The hull and turret front as well as the turret sides, on the other hand, are protected by composite armor, as they are more frequently exposed to enemy fire. In search of composite armor for the XM815 tank, an American delegation visited Chobham in July 1973 to find out about the Burlington composite armor developed by the British . Impressed by the results, the Ballistic Research Laboratory at Aberdeen Proving Ground began developing “Chobham armor”, which was specially tailored to the needs of the tank, now known as the XM1. In February 1978 the first M1 pre-production models with Chobham armor were finally handed over to the US Army. In 1984 the M1 production was converted to the M1 IP (Improved Protection) model. The turret front armor was changed again; instead of the "short" turret with a front thickness of about 650 mm, only M1 with "long" turrets with a front thickness of about 880 mm were built from then on in order to create more space for the composite armor. As a result, the vehicle weight increased from 55.7 t to 57 t. Like the Challenger 1 , the M1, M1 IP and M1A1 versions are equipped with classic Chobham armor, the exact structure of which is subject to confidentiality. However, the construction will be similar to the armor of the Leopard 2 A1-3, which according to RM Ogorkiewicz of the Jane's Information Group consisted of ceramic, hardened steel plates and aluminum. Interestingly, the structure is thus similar to a RARDE armor, which was presented in 1995 in the International Journal of Impact Engineering . This consists of aluminum oxide , steel and fiberglass-reinforced plastic . The aluminum plate as “backing” would also explain the somewhat better protection values ​​of the Leopard 2A1-3 against impact projectiles due to the higher density. With the version M1A1 HA (Heavy Armor), as well as M1A1 HA + and M1A1 HC (Heavy Common), a composite armor of the third generation was changed, which contains an intermediate layer of depleted uranium. This is enclosed in steel to meet the demands for a hard and dense material. The vehicle mass rose to around 61.3 t, but the increase in weight due to the heavy metal layer and the larger 120 mm cannon may have been partially offset by lighter ceramics such as silicon carbide and contemporary fiber materials such as Kevlar. The versions M1A1 AIM and M1A1D also have this armor. The latest versions M1A2 and M1A2 SEP are rumored to be equipped with Dorchester armor like the Challenger 2 . This should consist of uranium dioxide nuggets and rubber, and tungsten should also be included. Presumably the "backing" will consist of more efficient Dyneema fibers. The combat weight increased here to up to 63 tons.

M1A2 SEP Abrams with TUSK
Shot down M1A1 in Iraq 2003

The TUSK program was launched due to the increasing number of tank failures in Iraq when used in built-up areas. TUSK stands for Tank Urban Survival Kit and is an add-on kit for the M1 Abrams to increase survivability during operations in built-up areas. The ARAT reactive armor (Abrams Reactive Armor Tiles) is mounted on the side skirts. Another reactive armor, known as ARAT II, ​​is supposed to protect the sides of the turret better against shaped-charge weapons and projectile-forming charges . A 1360 kg heavy V-shaped armor reinforces the underside of the vehicle hull against mines and booby traps. As in the Leopard 2A6M, the driver's seat is suspended from the vehicle ceiling using four belts; the decoupling of the driver's seat from the tub floor reduces the risk of injury or death to the driver due to the elastic deformation of the tub floor in the event of a mine explosion under the tub. In addition, cage armor can be attached to the rear .

The softkill system AN / VLQ-6 Missile Countermeasure Device (MCD), which is also known as HardHat , has been available since 1991 . The system is mounted on the turret in front of the loader's hatch, with the M1A2 the commander's independent thermal imaging device is located here. The jamming transmitter with an elevation coverage of 12 ° and an azimuth coverage of 40 ° is intended to outshine the infrared source at the rear of the missile, so that the steering system of the launcher is disrupted in SACLOS -guided anti-tank weapons. The cross-fading should take place from about 50% of the shooting distance, i.e. at about 1000 m when shooting from a distance of 2000 m. Since the jammer on the M1 appears in the crosshairs at the top right from the point of view of the launch device, the trajectory of the guided weapon is permanently corrected to the bottom left, which can lead to hits on the ground. Later the improved version AN / VLQ-8A was bought. The system can also be used on the M2 / M3 Bradley and is only installed when required. In addition to manual nebulization through the smoke grenade launcher systems of the type M250 (six thrower per tower side) or M257 (eight per launcher side of the tower), the system can still be combined with the M6-thrower to smoke grenades and flares fire. All M1 are also equipped with a vehicle-engine-exhaust smoke system (VEESS) , which enables fogging by injecting diesel into the exhaust system. In vehicles that are operated with JP-8, the system is no longer functional.

Additional accessories can be mounted on the tank to increase its survivability. For example, a mine plow, mine rollers or a clearing shovel can be attached to the front of the tub to remove barriers. Australian M1 AIMs are still equipped with Saab's Barracuda camouflage system. It is estimated that the different versions of the M1 Abrams have the following armor protection in RHA equivalent against HEAT and KE bullets :

M1 Abrams M1 IP / M1A1 M1A1 HA M1A2 M1A2 SEP
Tub front (KE) 400 mm 490 mm 590 mm 625 mm 625 mm
Bathtub front (HEAT) 700 mm 800 mm 800 mm 1050 mm 1050 mm
Tower front (KE) 400 mm 450 mm 680 mm 900 mm 960 mm
Tower front (HEAT) 700 mm 920 mm 1320 mm 1620 mm 1620 mm

Drive and drive

M1A1 Abrams off-road in Iraq

The M1 is powered by a Lycoming Textron AGT1500 gas turbine , which is controlled by a Digital Electronic Control Unit (DECU) . The unit was developed from the PLT27 gas turbine in the 1970s. The advantage of this drive concept is that a gas turbine is significantly smaller and lighter than a diesel engine of the same power. The turbine weighs only 1134 kg (2500 lb). In addition, the turbine does not require any cooling liquid and almost any flammable liquid can be used as fuel in any mixing ratio. For practical reasons, gasoline , diesel and kerosene are used for this. The US Army used diesel as fuel until the early 1990s, after which it was switched to JP-8 for logistical reasons . The Australian Army still uses diesel. The complete drive unit consists of the air filters on the left and right of the turbine, the twin-shaft gas turbine with recuperator and reduction gear (7.5: 1), the hydromechanical shift, reversing and steering gear X-1100-3B from Allison Transmission with six gears and two Coolers. The gas turbine is installed lengthways and in the center of the rear of the tank and forms a "T" with the gearbox.

The AGT1500 gas turbine has a modular structure and consists of four parts: the front part consists of the compressors and combustion chamber, the rear part consists of the turbine and recuperator, the reduction gear and external attachments such as the starter or the adjustment mechanism of the guide vanes. The starter is an electric motor with 5500-9000 rpm, which uses an auxiliary gear to bring the high-pressure stages of the gas turbine up to speed until it ignites. The sucked in air is freed of impurities by the air filter and compressed by the five-stage axial compressor of the gas turbine. The following high-pressure compressor has four axial and a final radial compression stage and compresses the air further to a pressure of 14-16 bar. Bleed air for cooling engine parts is also discharged here. The working gas then flows through the recuperator in the rear of the turbine and from there into the combustion chamber. As in the Pratt & Whitney JT9D, the combustion chamber and injection nozzles are made of a nickel-thorium dioxide alloy, with radioactive thorium accounting for around 2%. The single-stage high-pressure turbine is air-cooled and drives the high-pressure compressor. The following single-stage low-pressure turbine rotates in opposite directions and drives the low-pressure compressor. Then the drive shaft is driven by an uncooled axial turbine, the stator of the stage being equipped with movable guide vanes. The exhaust gas is then led up through the recuperator and discharged through an exhaust duct above the gearbox in the center of the rear. The exhaust gas temperature is around 500 ° C, since the recuperator should heat the compressed air in front of the combustion chamber as much as possible. The drive power of the turbine is transferred to the main gear via a reduction gear built into the recuperator, whereby the speed in the reduction gear is reduced from 22,500 / min at rated power to 3000 / min while the torque increases. The mass throughput through the turbine is around 5.36 kg / s at nominal power.

Engine change on an M1A1. The black opening in the middle of the rear is the end of the exhaust duct with the radiator to the side.

In contrast to diesel engines, gas turbines have a different torque and power curve. In principle, the performance curve of gas turbines is flatter than that of piston engines. This means that a high drive power is also available in the lower speed ranges. As with all turbo machines, the power curve is roughly logarithmic: at 40% speed, around 67% of the power (746 kW) is provided, at full speed of 3000 rpm 100% power (1119 kW). The torque curve is linear and descending, which gives the tank excellent elasticity : 6000 Nm is available at around 30% speed, and this drops to around 5000 Nm at 65% of maximum speed. This is given as 3000 rpm, with a controller preventing speeds of over 3100 rpm. In combat operations, the turbine runs in tactical idle mode. The idling speed is increased from 870–950 rpm to 1250–1350 rpm, thereby improving the tank's response and acceleration behavior. Interestingly, the AGT1500 can deliver almost 800 kW of power at 1300 rpm; even when driving (under load) at idle , the gas turbine releases 40% more power than the engine of the predecessor model M60 at full load. However, this leads to a significantly higher fuel consumption, which is almost as high in idle as at full load. During the troop trials for the Swedish army (1993/1994), the M1 had an average consumption of 1480 l / 100 km, which was roughly double that of the Leopard 2 competitor model .

While the engine noise in a piston engine is emitted through the exhaust system, the operating noise of a turbine occurs on the compressor. The necessary air filter in front of the compressor reduces the noise - this and the great smoothness of its operation earned the M1 Abrams the nickname whispering death during its first REFORGER maneuver . The AGT1500 turbine was originally intended to be replaced by the LV100-5, which was developed for the ASM program's Block III tank . Compared to the AGT1500, the fuel consumption could be reduced by 33% in normal operation and by 50% in idle. The power-to-weight ratio has also been improved, the number of components reduced by 43% and reliability increased by over 400%. After the cancellation of the XM2001 program, the LV100-5 gas turbine is now being further developed by Honeywell and General Electric under the PROSE (Partnership for Reduced Operating and Support Costs, Engine) program of the US Army . In 2006, Honeywell International was commissioned with the AGT1500-TIGER program as part of PROSE Phase 1. The aim of the program is to increase the service life of the engines, some of which are 30 years old, from 700 to 1400 operating hours.

Driver's seat with handlebar. The speed steps R, N, D and L can be seen, where N was selected.

Allison Transmission's X1100-3B hydromechanical shift, reversing and steering gear accelerates the tank to its maximum speed, which according to US Army technical instructions is 40-50 mph (64-80 km / h) at 1500 hp and 3000 rpm lies. The exact maximum speed depends on the subsurface and on whether the turbine is "open"; speeds of 3500 rpm and speeds of over 100 km / h can be achieved. The transmission is also modular and consists of four assemblies: the input module with the torque converter, the middle section with the manual transmission, the hydrostatic pump, and the output modules on the left and right, which contain the brake and summing gear . The power is transferred from the gas turbine to the torque converter via a further transmission; Mechanical converter lock-up takes place at similar input and output speeds. The automatic gearbox has six gears, four of which are installed for forward travel and two for reverse travel. The driver can choose between four speed levels:

  • R (reverse): backward travel. The transmission changes between gears R1 and R2.
  • N (neutral): To rotate the Abrams around its vertical axis while standing. Driving is not possible.
  • D (drive): Forward drive , whereby the transmission only uses gears 2, 3 and 4.
  • L (low): Forward travel with all gears that are further extended.

There is also a hydraulic pump in the gearbox, which builds up the oil pressure for the steering and the parking brake. The power of the motor is passed on to the left and right of the gearbox at the same speed via the zero shaft to the output modules, where a summing gearbox combines this with the speed of a hydraulic motor to enable cornering and turning around the vertical axis. The driver determines the oil flow rate of each hydraulic motor by steering. In contrast to the Leopard 2, the system is much simpler, as no additional hydrodynamic couplings are used to split the power flow. The brake is also much simpler: the output modules contain oil-cooled multi - disc brakes, which decelerate the tank and can act as a parking brake. In order to be able to generate the brake pressure even when the gas turbine is switched off, the hydraulic pump also feeds a pressure reservoir. In contrast, the Leopard 2 uses three brake systems on each side: a wear-free hydraulic flow brake and brake discs in the transmission, as well as disc brakes integrated in the side transmission as a parking brake. After the output modules, the power of the AGT1500 is transferred to the side gears, which are integrated into the drive wheels as planetary gears. The waste heat from the transmission, the hydraulics and the disc brakes is released to the rear to the ambient air via heat exchangers through which oil flows to the left and right of the exhaust duct. The fans of the heat exchangers are driven by the input module. The heat exchangers also contain the vehicle-engine-exhaust smoke system (VEESS) to fog up the tank by injecting diesel (if this is used as fuel), since an injection into the exhaust jet would result in an afterburner flame.

Abrams tanks on the march, with tow bars and a clearing shovel at the front of the tub

The complete drive unit can be removed within an hour using a crane. Due to the modular design, however, 70% of all parts can be removed without removing the entire unit. When completely dismantled, the gas turbine, gearbox and the two coolers are lifted out of the tank with the help of a sling. The three air filters, which consist of two-stage centrifugal separators and subsequent fine filters, remain in the vehicle. When reinstalling, the connection between the air filters and the gas turbine must be tight, otherwise there is a risk of damage from foreign objects , which can be a problem in sandy areas. In the second Gulf War in 1991, many M1s were put out of action by clogged air filters, as they quickly reached their limits in the dusty desert regions. Based on this experience, an integrated air filter cleaning system was designed that blocks the air inlet to one filter and then cleans it with air blown in from the rear while the other two air filters continue to work. In this way, all filters can be cleaned one after the other without having to turn off the turbine. The replacement cost of an air filter is only $ 120, and it takes about half an hour to change.

The M1 has a total of 1911 liters of fuel, distributed over four tanks. The M1A2 SEP only has a capacity of 1680 liters as one of the tanks has been removed to make room for a generator. Therefore, during the Iraq war in 2003, rubber bladders ( collapsible fuel bags ) with a capacity of 303 liters were carried on the tanks in order to increase the fuel supply. However, this measure was only carried out in relatively safe situations such as troop transfers, the bubbles were not used in combat situations.

Rear view of a USMC Abrams. In the middle a part of the deep water equipment .

The suspension of the tank is carried out via a hydromechanical suspension system, which consists of seven swing arms on each side. The swing arms are connected to torsion bars made of high-strength steel, which run across the tub and are fixed on the opposite side. The maximum spring travel for the rollers is 381 mm. There are also three rotating shock absorbers on each side, which are connected to the first, second and seventh rollers. At the top of the drive there are two support rollers on each side to prevent the chain from sagging. A "living" serves as a track connector track the company Diehl type 570 N or 570 P3 / P6. The vehicle is capable of foraging up to a depth of 1.2 m. The United States Marine Corps also procured the Deep Water Fording Kit (DWFK) for deep wading, which consists of an exhaust duct and two air inlet pipes. During the land march, the shafts are pushed into one another and transported in the storage grid at the rear of the tower. When wading, the air inlet ducts are located on the fan grille on the left rear of the tub, the exhaust duct is attached to the center of the exhaust grating. This enables a fording depth of 2.37 m to be achieved. After wading through, the shafts can be scraped off by rotating the tower.

Optics and sensors

USMC gunner looking through the main scope of an M1A1.
The commander at his workplace in an M1A1. In front of him is the view of the gunner's main telescopic sight. On the right below the corner mirror is the periscope for the 12.7 mm machine gun.

The commander has a total of six corner mirrors at his disposal, which allow him a 360 ° all-round view, as well as a three-fold magnifying lens for the M2 machine gun. The gunner's main telescopic sight can also be accessed via an optical connection. This gives him all the options of the fire control system for on-board cannons and turret machine guns. He can override the gunner in the normal and emergency operation modes . From version A2 onwards, the commander also has his own independent thermal imaging device at his disposal, which enables him to fight targets using the hunter-killer method.

The gunner has access to the main rifle scope (Gunner's Primary Sight - GPS), a day vision channel and the thermal imaging channel of the thermal imaging device (Thermal imaging sight - TIS), which is bundled together with the laser rangefinder in the armored viewing head on the right side of the tower. The day vision channel as well as the thermal imaging device have a three-fold and a ten-fold magnification. Experience from the Second Gulf War showed that the effective range of the main weapon was greater than the distance at which targets could still be made out with the thermal imaging device. The TIS of the M1A2 SEP therefore has three, six, 13, 25 and 50 times magnifying optics.

The line image in the GPS was also stabilized in the horizontal axis up to the M1A2 in order to compensate for the lack of full stabilization of the field of view for cost reasons. This was only done through the tower. The system known as Line of Sight Compensation leads to a lateral trembling of the line image, which is noticeable at greater distances through a lower image resolution in the eyepiece. The M1A2 stabilized the line of sight in both axes. If the primary optics fail, the gunner still has an auxiliary rifle scope (Gunner's Auxiliary Sight - GAS) with single or eight-fold magnification. This is not stabilized, but the exit is in the cannon aperture below the axially parallel machine gun, so that the optics always remain aligned with the axis of the cannon.

As a means of observation, the loader has a single corner mirror that can be rotated 360 degrees and has a simple magnification. The driver has three corner mirrors facing forward, front left and front right.

Fire control system

The fire control system consists of a Nd: YAG - laser rangefinder of Raytheon Systems Company , a digital fire control computer by General Dynamics Canada and the stabilized optics of the gunner. The laser measures distances up to 7,990 meters with an accuracy of 10 meters, whereby the fire control computer only takes into account distances between 200 and 4,000 meters. To avoid multiple echoes, ARM 1ST RTN or ARM LAST RTN can be used to choose between first and last echo utilization. Main battle tanks of the US Marine Corps, on the other hand, are equipped with the eye-safe laser rangefinder (ELRF - eyesafe laser rangefinder) from Carl Zeiss Optronics. With a measurement accuracy of 5 meters, the maximum range is 9995 meters. The stabilization allows the gunner to aim precisely at a target even while driving and to determine the distance with the laser rangefinder. From the determined distance, the data of a cross wind sensor installed on the tower roof, the temperature of the propellant charge, a tilt sensor and the collimator mirror at the muzzle, the necessary tube elevation and the lead angle are then calculated and shown to the gunner on his display. This type of data acquisition for fire control enables a very high first-shot hit probability both when fighting from positions and while driving. According to the US Army, the main weapon is more precise than a sniper rifle at distances of more than 1200 meters.

Technical specifications

designation M1A2 Main Battle Tank
Type: Main battle tank
Crew: 4th
Engine: Textron Lycoming AGT 1500 gas turbine
Power: 1119 kW (1500 HP) at 22,500 rpm
Transmission: Allison X-1100-3B automatic steering gearbox
Landing gear: torsion bar sprung support roller drive
Length over all: 9830 mm
Width over everything: 3657 mm
Height above everything: 2885 mm
Ground clearance: 483 mm
Wading ability : 1219 mm
Trench crossing ability: 2743 mm
Climbing ability: 1067 mm
Gradeability : 60%
Bank slope: 40%
Combat weight: 63,086 kg
Ground pressure : 15.4 PSI [1.055]
Maximum speed road: 68 km / h
Top speed terrain: 48 km / h
Fuel quantity: 1908 liters
Driving range: 426 km
Armament: M256 cannon, 2 × M240 machine guns, 1 × M2 machine gun
Ammunition: 40 cartridges for the cannon; 12,400 cartridges for the M240, 1000 cartridges for the M2

commitment

Mission profile

M1A1 Abrams during a 2005 exercise

The original main task of the M1 was to carry out rapid advances and destroy enemy tanks in combined arms combat in conjunction with the M2 Bradley infantry fighting vehicle. Combat battalions were formed from two companies of M2 Bradley and two companies of M1 Abrams during Operation Desert Storm. The M1 formed the top during the attack due to their better armor, while the M2 took over the flank protection and could carry out attacks on their flanks when they encountered opposing forces. Since the end of the Iraq war, the M1 has continued to be used by the troops stationed there. However, his main focus has shifted from fighting enemy tanks to supporting his own infantry in built-up areas.

Calls

An M1A1 fires at enemy forces in a building during Operation Phantom Fury

Since its commissioning, the M1 has been involved in all major US military operations, including Operation Desert Storm and the Iraq War .

At the beginning of the second Gulf War, there were a total of 3,113 Abrams in the Gulf region, with 2,024 active units assigned and 1,089 tanks held in reserve . In the active units, 94% of the tanks were of the M1A1 type and 6% of the original M1 type. In general, the Abrams stood out for its high availability (90% and more during ground battles), mobility and firepower, with the harsh climate of the Iraqi desert also leading to maintenance issues. The air filters and fuel pumps in particular proved to be error-prone and often had to be replaced. The high fuel consumption also caused problems with replenishment and reduced the operational range. In addition to the very good offensive performance of the Abrams, its armor and safety design also showed hardly any weaknesses. A total of nine vehicles were destroyed, seven of which were shot at by our own troops and two by deliberate detonation in order not to leave stuck tanks to the enemy. In addition, 14 Abrams were damaged by mines or enemy fire, with Iraqi T-72s taking at least seven direct hits. During the entire operation, not a single Abrams was destroyed by enemy fire, not even in multiple hits.

M1A1 crosses the Euphrates over a pontoon bridge

During the conflict there was a great advantage over the T-72M1 used by the Iraqis, which formed the core of the Iraqi armored forces. Thanks to the more powerful thermal imaging devices and fire control system, the M1 was able to effectively fight the Iraqi tanks at distances of over 3000 m even in poor visibility conditions, caused by fog or the smoke from burning oil wells. The M829-type mass ammunition used also proved to be effective in penetrating the T-72 armor. Two tanks of this type could be eliminated with a single shot, as the penetrator completely penetrated the first tank and then switched off a second tank behind it (in total the T-72 armor was penetrated three times in a row). In another case, a ten-meter-thick sand barrier could not protect the T-72 behind it from destruction. Due to the high performance of the M829 projectile it was nicknamed "silver bullet" ( English silver bullet ).

Due to its use in Iraq and the natural vulnerability of battle tanks in built-up areas, the number of losses from IEDs and massive close-range fire from RPGs has meanwhile increased significantly. Since Operation Iraqi Freedom began , 80 M1s have been so badly damaged that they had to be returned to the United States. Of these 80, 63 were repaired and put back into service; the remaining 17 were so badly damaged that repairs were no longer economically viable.

In November 2010 it was announced that the US was planning to deploy 16 M1s in Afghanistan in Helmand Province.

User states

Worldwide use of the M1 Abrams

In addition to the USA, which still has a fleet of 5970 M1s in various versions, the following countries are also users of the M1, albeit to a much lesser extent. The relatively low export figures are due to various reasons. Many NATO countries have their own main battle tank developments, so buying an M1 is not necessary. In many cases, the high fuel consumption was the decisive factor against the purchase, as the logistics capacities would have to be expanded at the same time. For this reason, a variant of the M1 was developed that is equipped with a diesel engine from MTU Friedrichshafen . So far, however, no buyers have been found for this variant. Many states refrain from purchasing the M1 due to the high costs.

Australia

Australian M1A1 AIM with three-color camouflage.

In 2004, the Australian Department of Defense announced that the Land 907 Tank Replacement Project was planning to purchase 59 M1A1s to replace the Leopard 1 AS1. Despite the many increases in combat value, it is no longer technologically competitive with third-generation battle tanks. In addition, the Australian military wanted to achieve a system of equality with the US armed forces in order to simplify the logistics for joint operations. The vehicles were delivered until 2007, with the first 18 arriving in September 2006. Of the 59 purchased vehicles of the type M1A1 AIM, 41 are used in the 1st Armored Regiment, the rest are intended for practice and training purposes. All tanks come from the reserve stocks of the 7th US Army . The contract was valued at $ 475 million. In addition to the battle tanks, this included seven M88A2 HERCULES recovery tanks, eight fuel trucks, 14 heavy-duty transporters, spare parts and training simulators. The original standard camouflage color "sand yellow" of the battle tanks was changed to the Australian three-color camouflage from November 2009. The camouflage takes place during the depot repair cycles, so that there will be both variants during this period.

Egypt

Egyptian M1 Abrams in Cairo , 2011

In 1989, Egypt was added to the US list of its most important allies outside of NATO . This gave the country preferential access to selected armaments programs. In addition, the army wanted to retire the predominantly Soviet equipment and replace it with more modern equipment. Egypt became the first export customer for the M1; 555 M1A1s had been delivered by 1998. The final assembly took place in Egypt, with 35% of all parts being manufactured in Egypt and the rest being supplied from the USA. In 2002 General Dynamics was commissioned to support the Egyptian arms industry in the production of its own M1. Since then, another 325 tanks have been manufactured or assembled in Egypt. A further 125 units are to follow by 2011, which will expand the stock to 1,005 vehicles. Overall, Egypt plans to expand its M1 fleet to 1,500 vehicles. The Egyptian M1A1 are almost identical to the US-made examples, but do not have the improved front armor.

Iraq

Iraqi M1A1M in January 2011

Since a large part of the tank units were destroyed during the Gulf War in 1991 and the Iraq War and the existing battle tanks are out of date, Iraq applied for a supply of new material in 2008 in order to increase the previously weak anti-tank capabilities. The Iraqi armed forces received a total of 140 M1A1Ms (disarmed variant without the uranium armor) between August 2010 and August 2011. The delivery also includes armored recovery vehicles, supply and ambulance vehicles, heavy-duty transporters and spare parts. In October 2012 it was announced that six additional tanks had been delivered.

According to the Peshmerga, during the civil war in Syria , the Islamic State captured several M1 Abrams tanks that were left behind by the fleeing Iraqi army.

Kuwait

Kuwaiti M1 Abrams main battle tank in 2011

The armed forces of Kuwait suffered heavy losses in men and material during the Iraqi invasion. After the liberation, the land forces were quickly rebuilt, with a focus on modernizing the armored force. Due to the success of the M1, Kuwait decided to purchase 218 M1A2 from US stocks. These were delivered in three lots until 1996.

Morocco

In 2015 the Royal Moroccan Armed Forces ordered 222 M1A1 SA (situational awareness) tanks. These vehicles came from the inventory of the United States Army. Before delivery, the tanks were overhauled and modernized at General Dynamics . There they received new optics and improved armor. The tanks were delivered to Morocco in two lots between 2016 and 2018 .

Saudi Arabia

After the end of the Gulf War, Saudi Arabia wanted to modernize its armored forces with the Leopard 2 . One argument for this was the 120 mm smoothbore cannon . However, due to export restrictions for the Leopard 2 , it could not be purchased. Therefore 315 M1A2s were acquired between 1994 and 1996 with this same German smoothbore gun. The Saudi tanks have a different radio system and a new vehicle information system, the designation is M1A2S. Saudi Arabia currently has 595 tanks.

Greece

In autumn 2011, US officials agreed to give Greece 400 M1A1 Abrams from their holdings. The tanks are to be technically upgraded to upgrade their capabilities. The funds for the transport and the increase in combat value are raised by Greece.

In addition to Greece, the Abrams was tested by Sweden, Switzerland and other countries, but only accepted by Greece as a battle tank in the troops. The rest of these states now have Leopard 2 main battle tanks. In addition to the M1 Abrams, Greece also uses the Leopard 2 in the A6 HEL variant.

variants

M1A2 of the 3rd US Armored Cavalry Regiment in Tal Afar / Iraq . On the left side of the turret in front of the loader the commander's independent thermal imaging device.

Improved M1

Since the design of the M1 was designed from the outset to accommodate the 120 mm smoothbore cannon, the Army decided in 1981 to equip 14 tanks with the new weapon on a trial basis. In addition, further modifications were made, including improved armor on the turret and hull, modified ammunition holders for the new ammunition, the installation of an integrated NBC protection system with new air filters, a storage box on the turret rear and a new turret drive. The designation of the test copies was M1E1. During the testing of the cannon, the Army decided that the changes that were already ready for series production should be carried over into ongoing production. Because of this, some changes were made to newly produced vehicles from 1984 onwards. The changes included improving the armor and attaching the storage box to the rear of the turret to give the crew more space to store their personal equipment. A total of 894 copies were made before production was switched to the A1 model. Vehicles of this first increase in combat value are no longer in service with the US Army, a few examples were still in use by the National Guard until 1997. All other vehicles were converted or stored for later conversions.

M1A1 / M1A1D

The first M1A1 was manufactured in August 1985. This variant already contains the changes to the Improved M1. The main innovations were the replacement of the 105 mm cannon with a license production of the 120 mm smooth barrel cannon from Rheinmetall and the implementation of the Product Improvement Program (PIP). This included the installation of an NBC protection system that simultaneously functions as air conditioning and heating. Other small changes were made to the chain aprons of the drive, the gearbox and the seats for the loader and commander. A total of 2388 M1A1s were newly manufactured, M1s that had already been produced were upgraded. Production of the M1A1 series ended in 1993 after a total of 4,796 vehicles were manufactured or converted. A variant of the M1A1, which has been equipped with the digital guidance and information system of the M1A2 since 2000, is known as the M1A1D.

M1A1 HA

In 1988, the Army asked for a version of the M1A1 with improved armor. In order to stay within acceptable weight limits, depleted uranium was chosen as the armor material. This is installed between two layers of steel in the tower front. Due to this construction and the low radiation of the depleted uranium, this type of armor was classified as harmless by the US Nuclear Regulatory Commission. This variant, which was produced until 1993, is known as the M1A1 HA ( H eavy A rmour), 1328 copies were produced. A further 834 main battle tanks carried the HA + identification and again had improved uranium-containing armor. These versions are outwardly indistinguishable from a vehicle without uranium armor.

M1A1 HC

This type of Abrams was tailored to the requirements of the United States Marine Corps and was based on the M1A1 HA +. The variant known as Heavy Common also had technical changes that are necessary for the operational area of ​​the marine infantry. The battle tanks were equipped with deep water equipment, a vehicle navigation system and better protection against corrosion. A total of 329 M1A1 HCs were manufactured by General Dynamics.

M1A1 AIM

M1A2 with TUSK in prototype status.

As part of this program, US Army M1A1 tanks were completely dismantled into their individual parts and then reassembled using refurbished parts. This is why these vehicles were classified as “brand new” with zero operating hours. The aim was to align the design status of the different M1A1 equipment statuses. Furthermore, some innovations were built in to improve the maneuverability of the tank. The innovations included the installation of digitized communication facilities (internal and external) as well as new operating devices for the commander. A power generator at the rear should reduce fuel consumption when the vehicle is stationary. A separate thermal imaging device was also installed to operate the commandant's heavy machine gun. M1A1 older construction lots were used for the conversion. From 2000 onwards 45 M1A1s, later 135, were upgraded to M1A1 AIM and returned to the US armed forces. A battalion was always fully equipped and included 44 main battle tanks with new regulations, spare parts and kits. Tanks for export also went through the AIM program.

M1A2

At the end of 1988 General Dynamics Land Systems was entrusted with another combat enhancement program. The focus should be on increased armor protection, increased survivability and improved maneuverability of the vehicle. Due to the increase in weight to 61.7 t, not all of the Army's wishes for additional armor could be implemented. To improve maneuverability, an independent thermal imaging device was installed for the commander (Commander's Independent Thermal Viewer - CITV), all existing thermal imaging devices were converted to 2nd generation units, the electronics were revised and an Inter Vehicular Information System (IVIS) was integrated into the system which allows the exchange of location data between the individual vehicles. In poor visibility, the CITV allows the commander to observe independently of the shooter's thermal imaging device. Furthermore, the commander's weapon station was improved and a Hull Power Distribution Unit was built into the hull for better energy supply to the electrical systems. In order to increase the endurance of the vehicle, a power generator with 6.2 kW output was attached to the rear. Before this measure, the turbine had to continue idling to ensure the power supply. The ammunition magazine in the turret rear has also been revised so that two additional cartridges can be stored there. The first vehicles of the M1A2 were delivered in 1992; production ended in 1996 after export customers such as Saudi Arabia had been supplied. Older versions are currently being converted to the A2 model. Outwardly, the M1A2 differs from the earlier versions by the CITV in front of the loader hatch. According to the Army, the M1A2 can detect targets 45% faster, the handover from the commander to the shooter is up to 70% faster and the position of targets is up to 32% more precise than the M1A1.

M1A2 SEP

The SEP (System Enhancement Program) includes some points that are intended to improve both manageability, endurance in combat and combat strength. For this purpose, a new second-generation thermal imaging device was installed for the commander, a new eye-safe laser rangefinder was installed, and digitized maps were integrated into the system on a color display for the commander. The performance of the computer system has also been improved, the memory has been expanded and a new operating system with upgrade potential for future combat value increases has been installed. The armor on the turret front and on the sides has been increased once more. According to the Army, the maximum shooting range increased to 4000 meters. Air conditioning for the electronics and the crew was installed in the fighting compartment. The M1A2 does not have a generator set, but it is possible to install one in the rear under armor protection. To ensure the functionality of the electrical systems even when the turbine is switched off, additional high-performance batteries were installed at this point.

M1 TUSK

Tower view of an M1A1 with the TUSK-I upgrade kit. You can see the CS / AMM mount on the on-board cannon, the RTS on the commandant's machine-gun mount and the LAGS of the loader. On the sides of the tower, the typical US smoke thrower.
An M1A1 with turret position at 9 o'clock. The CS / AMM mount with Browning M2 on the on-board cannon. The climbing aids of the ARAT-I reactive armor can be seen on the chain aprons.
The ARAT-I reactive armor from the side. The CS / AMM mount of the M1A1 is not armed.

The TUSK program was launched due to the increasing number of tank failures in Iraq when used in built-up areas. TUSK stands for Tank Urban Survival Kit and is an add-on kit for battle tanks to increase the survivability of operations in built-up areas. The set-up kit manufactured by General Dynamics Landsysteme largely consists of components introduced from existing systems. In August 2006, the US Army Tank-Automotive and Armaments Command (TACOM) ordered 505 kits in a first lot for a total price of 45 million US dollars. From summer 2007 to April 2009 the M1 Abrams were retrofitted in Iraq. The installation of the complete TUSK-I conversion kit takes twelve hours.

Because the variants are used differently, different conversion kits have also been introduced. The upgrade kit designated as TUSK I is available for both the M1A1 and the M1A2 SEP and includes the following components:

  • Reactive armor ARAT I (Abrams Reactive Armor Tiles)
ARAT is based on the reactive armor of the M2 / M3 Bradley and uses handling-safe explosives. ARAT I consists of 64 segments that are attached to the chain aprons in two rows of 16 on each side. The tiles designated as XM19 protect against shaped charges.
  • Protective shield on the mount of the loader (Loader's Armor Gun Shield - LAGS)
The LAGS, consisting of a 200 mm high ring and a protective shield, protects the loader when operating his machine gun. The ring around the loader hatch and the shield are made of armored steel and armored glass.
  • Remote Thermal Sight - RTS
The uncooled thermal imaging device (WBG) of the 2nd generation enables the commander of the M1A1 for the first time to attack targets at night and in all weather conditions with his machine gun. The image generated by the WBG is displayed on the commander's monitor (DCM; Display Control Module). It is mounted axially parallel to the M2HB on the mount.
  • Thermal imaging device for loaders (Loader's Thermal Weapon Sight - LTWS)
Thermal imaging device AN / PAS 13
The loader’s thermal imaging device comes from the US Army's land warrior program. The AN / PAS 13 manufactured by Raython Network Centric Systems is mounted on the Picatinny rail of the M240B. The device, which is connected to the power distribution box (PDB) via a cable, allows the loader to detect and combat targets up to a distance of 550 meters. A helmet display (Helmet-Mounted-Display - HMD) with a resolution of 800 × 600 pixels projects the images in front of the user's eyes.
  • Thermal imaging device for the driver (Driver's Vision Enhancer - DVE)
The DVE gives the driver a better view at night and when there is dust and smoke development. The thermal imaging device, which consists of a sensor module (SM) and a control screen (DCM), has a 10.4-inch display with a resolution of 800 × 600 pixels. The sensor module consists of a 640 × 480, 8–12 µm microbolometer detector, which can be used to detect vehicles up to a distance of 1790 m. In combat conditions, a person can be recognized up to 190 m. The DVE used in exchange for the central corner mirror can be used in the temperature range from -37 ° C to +49 ° C.
  • Outboard station (Tank Infantry Phone - TIP)
The TIP is an outboard station on the right rear of the Abrams. The device integrated in the on-board communication system is an additional selector switch of the system and enables the user to speak to the tank crew, to listen in on the radio traffic or to make a radio message himself.
  • Power Distribution Box (PDB)
  • MG mount on the on-board cannon (Counter Sniper / Anti Material Mount (CS / AMM))
The Counter Sniper / Anti Material Mount is a heavy MG mount for the Browning M2 HB or M240 B. The mount enables a second MG to be installed coaxially with the on-board cannon on its faceplate and used against snipers, tank destruction troops and other targets at close range. If the mount carries the M2HB, targets can be fought up to a distance of 2000 meters. The tank's fire control system is used for aiming and aiming; the weapon is operated completely under armor protection. The equipment also includes a xenon searchlight, which is connected to the power distribution box by an armored cable duct. The aperture MG and the CS / AMM-MG can be used at the same time.
  • Abrams Belly Armor
The V-shaped armor reinforces the underside of the vehicle hull against mines and IEDs. The 1360 kg additional armor reduces the ground clearance by 200 mm.
  • Mine Resistant Driver Seat
The structure of the driver's seat corresponds to that of the German Leopard 2 A6M. Suspended from four belts on the vehicle ceiling and equipped with retractors (belt retractors), the driver can adjust his individual seat height (eye point) above and below the hatch almost continuously. By decoupling the driver's seat from the tub floor, the risk of injury or death to the driver due to the elastic deformation of the tub floor in the event of a mine exploding under the tank is reduced.
View of the cage armor on the rear of an M1
  • RPUSA (Rear Protection Unit Slat Armor)
The slat armor or cage armor on the rear of the vehicle was intended during the development of the TUSK program for the Abrams and was used in Iraq as early as 2004. According to the published documents of the Executive Office Ground Combat Systems (PEO GCS) program, it has not been part of the retrofit since 2007.

TUSK II further improves armor protection and protection against projectile-forming mines. Officially, this is limited to the M1A2 SEP and consists of the following components:

  • Reactive armor ARAT II
ARAT II reinforce the ARAT-I armor on the sides and are attached directly to the armor in the area of ​​the turret. The segments called XM32 have the shape of a roof tile and are attached at a slight angle to the ground. They improve protection against unconventional explosive devices (IED) and projectile-forming charges .
  • 360 ° protective shield for the commander
The protective shield system consists of armored steel and armored glass and encloses the commander's cupola. It gives the commander of the M1A2 SEP a better overview of the battlefield without sacrificing armor protection. The system only provided in the TUSK II was also slightly modified and installed on some M1A1s.
  • Reversing camera for the driver
The rear camera enables the driver to reverse without instructions from the commander or the loader. The camera developed by BAE Systems has a day vision and a thermal image channel. The image is displayed on the driver's screen and optionally on the commandant's display board. In addition to the M1A2 SEP, the M1A1 are also equipped with it.

TUSK III is planned again for the M1A1 and M1A2 SEP and includes the distance-active protection system TRAPS (Tactical Rocket Propelled Airbag Protection System), a mine-proof arrangement of the seats and a separate remote-controlled weapon station for the commander and gunner.

Vehicles based on the M1

M1 grizzly

Engineer tank Grizzly in the United States Army Ordnance Museum

The M1 Grizzly is a pioneer tank that is built on the hull of the M1. It was designed after the second Gulf War because it became apparent that the Army lacked engineer tanks that could follow the M1A1 in the attack. The 64 t grizzly has the same maneuverability as the M1A1 and offers protection against splinters from artillery projectiles. His job is to open mine barriers and remove obstacles such as trenches, barbed wire and rubble. Aids such as a wedge-shaped mine plow at the bow with automatic depth control and a rotating telescopic arm with backhoe bucket are available to him, which can also be used as a crane. The Grizzly is capable of a tank ditch to make in five minutes for a tank again traversable and to open a 600 m wide minefields within 21 minutes. The crew consists of two soldiers (driver and commander), the armament consists of a remotely controllable M2 machine gun. Due to a lack of funds, further development of the two prototypes was stopped in 2000.

M1 Abrams Panther II

The Panther II is a mine clearance tank, similar to the boar used by the Bundeswehr. It consists of an M1, whose turret has been removed to reduce weight, and a demining system attached to the bow. The tank does not require a crew due to a remote control system and can be remotely controlled up to a distance of 800 m. The mine clearance system consists either of a mine plow or a mine roller, which exerts a higher ground pressure than the tank itself through several heavy rollers and detonates anti-tank mines in the tank's lane. The Panther II can clear a 5000 m² minefield within an hour. The mine clearance tank is used by the KFOR armed forces and has also been used in Iraq since 2003.

M104 Wolverine

Main article: M104 Wolverine

The M104 Wolverine is a bridge- layer equipped with the German Iguana rapid tank bridge. Between 1997 and 2003, a total of 44 General Dynamics Land Systems were built and introduced. The originally planned total number of 465 vehicles was canceled after a budget cut.

Joint Assault Bridge

Prototype of the Joint Assault Bridge at a demonstration at Anniston Army Depot.

The USMC began using BAE Systems' titanium bridge system on the pan of an M1A1 in 2005 . After extensive troop trials and two prototypes, the armaments company received the order in 2007 to manufacture six bridge layers. With these vehicles it is possible to lay the scissor bridge of the bridge- layer M60A1 .

Assault Breacher Vehicle

Use of the mine clearance cords of the ABV to cut mine alleys.

The Armored Engineer Assault Breacher (ABV) is based on the M1A1 and is a development for the USMC. According to the plans, it is intended to clear obstacles and hit mine alleys. For the new tasks, the main battle tank turret was removed and replaced by a new turret construction that was provided with reactive armor. The crew is two people. For mine clearance, the tank has two 107 m long "mine clearing cords" (M58 Mine Clearing Line Charges - MICLIC) with C4 explosives (2.3 kg per 30 cm) on the tower roof, as well as various attachments for the front of the tub. By using a quick-change adapter (High-Lift Adapter - HLA), a V-shaped mine plow for openly laid mines (Surface Mine Plow - SMCD), a dozer blade (Combat Dozer Blade), a special mine blade from the M1 Abrams (Rapid Ordnance Removal System - ROPS) or a mine plow for the entire width of the vehicle (Full Width Mine Plow - FWMP). The cleared lane is marked for following vehicles by a marking system (Clear Lane Marking System) mounted on the rear. As with the Panther II, there is the option of remote control. A total of 52 vehicles are used by the USMC, another 187 vehicles have been ordered by the US Army, which has been using the system since 2010. The USMC first used it on December 4, 2009 during Operation Cobra's Anger when it stormed Now Zad in Afghanistan. The detonating cords were also used against fortified positions during the operation.

Abrams RV90 Armored Recovery Vehicle

This vehicle was an armored recovery vehicle on an M1A1 chassis. General Dynamics produced a prototype equipped with a crane on the left side of the tub and a clearing blade. After an unsuccessful comparison test between the ARV and the M88A2 HERCULES with its improved combat value , the project was discontinued in early 1990.

See also

literature

  • Christopher F. Foss : Jane's Armor & Artillery 2009-2010. Jane's Information Group Inc, 2009, ISBN 978-0-7106-2882-4 .
  • Michael Green, Greg Stewart: M1 Abrams at War. Zenith Press, St. Paul, MN 2005, ISBN 0-7603-2153-1 .
  • Rolf Hilmes: Main battle tanks today and tomorrow: Concepts - Systems - Technologies. Motorbuch Verlag 2007, ISBN 978-3-613-02793-0 .
  • Kevin C. Millspaugh: The M1 Abrams Tank: A Case Study in Major Weapon Systems Acquisition and Program Management. Naval Postgraduate School, Monterey 1995.
  • Carl Schulze: M1A1 / M1A2 SEP Abrams TUSK. In: Tankograd American Special. No. 3009, Tankograd Publishing - Verlag Jochen Vollert.
  • Steven Zaloga : M1 Abrams vs. T-72 Urals. Osprey Publishing, ISBN 978-1-84603-407-7 .

Web links

Commons : M1 Abrams  - album with pictures, videos and audio files

Individual evidence

  1. ^ History of the development of the M1, Section 8 globalsecurity.org. Retrieved January 22, 2010.
  2. Production figures , Section 16 Globalsecurity.org.
  3. ^ Average unit price Globalsecurity.org.
  4. a b Kevin C. Millspaugh: The M1 Abrams Tank. P. 21.
  5. a b c Kevin C. Millspaugh: The M1 Abrams Tank. P. 22.
  6. Kevin C. Millspaugh: The M1 Abrams Tank. P. 23 f.
  7. Kevin C. Millspaugh: The M1 Abrams Tank. P. 24.
  8. Kevin C. Millspaugh: The M1 Abrams Tank. P. 26 f.
  9. Kevin C. Millspaugh: The M1 Abrams Tank. P. 25 f.
  10. Kelly, Orr: King of the Killing Zone: The Story of the M-1, America's Super Tank. New York 1989, p. 121.
  11. ^ Walter J. Spielberger: From the tractor to the Leopard 2. Munich 1980, p. 230.
  12. a b c Kevin C. Millspaugh: The M1 Abrams Tank. P. 27 f.
  13. Kevin C. Millspaugh: The M1 Abrams Tank. P. 47.
  14. Kevin C. Millspaugh: The M1 Abrams Tank. P. 28.
  15. Kevin C. Millspaugh: The M1 Abrams Tank. P. 28 ff.
  16. ^ A b Robert S. Cameron: Pushing the Envelope of Battlefield Superiority. P. 10.
  17. a b Kevin C. Millspaugh: The M1 Abrams Tank. P. 30.
  18. United States. General Accounting Office: Large-scale Production of the M1 Tank Should be Delayed Until Its Power Train is Made More Durable: Report to the Congress. P. 1.
  19. ^ History of the development of the M1 globalsecurity.org. Retrieved September 27, 2009.
  20. Christopher Foss: Jane's Armor & Artillery 2009-2010. P. 165
  21. ^ Army looking into lighter Abrams tank www.armytimes.com. English, accessed March 14, 2011.
  22. The Abrams Tank - Next Generation. A Lighter and More Compact Tank www.usmilitary.about.com. English, accessed January 9, 2014.
  23. New Army tank could mean changes for M1A1 fleet ( Memento from September 10, 2012 in the web archive archive.today ) www.marinecorpstimes.com. English, accessed February 21, 2010.
  24. Michael Green / Greg Stewart: M1 Abrams at War. P. 105.
  25. dote.osd.mil accessed on March 4, 2016 (English)
  26. Leland Ness / Anthony Williams: Jane's Ammunition Handbook 2009-2010. P. 401
  27. Michael Green / Greg Stewart: M1 Abrams at War. P. 70
  28. M1028 Canister globalsecurity.org. Retrieved September 27, 2009.
  29. Product description ( Memento from January 19, 2012 in the Internet Archive ) (PDF; 2.0 MB) General Dynamics . Retrieved November 12, 2009.
  30. HE-OR-T globalsecurity.org. Retrieved September 27, 2009
  31. Michael Green / Greg Stewart: M1 Abrams at War. P. 63.
  32. DTIC - study of passive fuel tank inertion systems for ground combat vehicles
  33. International Journal of Impact Engineering 1995 Vol. 17, pp. 263-274
  34. a b army technology: M1A1 / 2 Abrams main battle tank
  35. ^ AHJ Claessen: Tanks & Pantserwagens - De Technische Ontwikkeling. Blaricum, 2003, p. 96.
  36. Preliminary study of defensive aids suite technology for the armor combat vehicle program (PDF; 633 kB)
  37. Collaborative Point Paper On Active Protection Systems
  38. Tank Protection Levels ( Memento of December 2, 2001 in the Internet Archive ) accessed on September 27, 2009 (English).
  39. ^ Nuclear Regulatory Commission - Federal Register Volume 62, Number 237 (Wednesday, December 10, 1997)
  40. Kampfpanzer.de - AGT1500  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Toter Link / www.kampfpanzer.de  
  41. CONSTRUCTION OF THE AGT 1500 C TURBINE ENGINE, SUPPORTING SYSTEMS, CONTROLS AND MONITORING DEVICES - M1 TANK  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Toter Link / rdl.train.army.mil  
  42. Honeywell: AGT1500 Turbine Technology
  43. Michael Green: M1 Abrams at War. Zenith Press, 2005, ISBN 0-7603-2153-1 , p. 117.
  44. Rolf Hilmes: Main battle tanks today and tomorrow. Motorbuchverlag, Stuttgart 2007, ISBN 978-3-613-02793-0 , p. 52.
  45. ADM Mar 2011: Land Force: Abrams takes Aim  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Dead Link / www.australiandefence.com.au  
  46. ^ A b Defense Industry Daily - Sustaining the M1 Abrams: US Army Puts a TIGER in its Tanks
  47. a b LESSON: INTRODUCTION TO THE X1100-3B TRANSMISSION, M1A1 ABRAMS TANK LEARNING OBJECTIVE  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Toter Link / rdl.train.army.mil  
  48. Joseph W. Anthony, John J. Moskwa, Eugene Danielson: Powertrain Simulation of the M1A1 Abrams using Modular Model Components. University of Wisconsin-Madison / US Army TACOM, Published February 23, 1998: “The AGT-1500 turbine output shaft's speed is reduced by a gearbox. This reduces the work turbine's approximate 26600 rpm maximum angular speed to an output shaft maximum speed of 3500 rpm. "
  49. ^ Rolf Hilmes: Main battle tank: The developments of the post-war period. Verlag Soldat und Technik im Umschau Verlag, 1980, ISBN 3-524-89001-6 , p. 57.
  50. Paul-Werner Krapke: Leopard 2. His becoming and his performance. Books on Demand GmbH, Norderstedt, ISBN 3-8334-1425-1 .
  51. United States Army Environmental Command: P2 Innovations - Air Filter Cleaning and Antifreeze Recycling. ( Memento from February 26, 2013 in the Internet Archive ) “The M-1 Abrahms (sic) tanks are used by the Blue Force rotational units when they do battle with the home team 11th Cavalry Regiment. Each tank has three air filters, and units are required to change all air filters on every vehicle three times per rotation, at a replacement cost of around $ 120 each. "
  52. CHAPTER 89 CLEANING INSTRUCTIONS - M1A1 AIM SA ABRAMS TANK (PDF; 2.7 MB).
  53. Michael Green, Greg Stewart: M1 Abrams at War. P. 118.
  54. Eyesafe Laser Rangefinder for the M1 Abrams Main Battle Tank. (PDF) Carl Zeiss Optronics, accessed November 1, 2009 .
  55. Michael Green, Greg Stewart: M1 Abrams at War. P. 77.
  56. Main Battle Tank. M1, M1A1, and M1A2 Abrams. In: fprado.com. Retrieved July 4, 2015 .
  57. ^ Steven Zaloga, Peter Sarson: M2 / M3 Bradley - Infantry Fighting Vehicle 1983-1995. P. 34.
  58. a b United States General Accounting Office - OPERATION DESERT STORM - Early Performance Assessment of Bradley and Abrams (PDF; 4.0 MB)
  59. Steven J. Zaloga: M1 Abrams vs. T-72 Urals. Operation Desert Storm 1991 . Osprey, 2009, ISBN 978-1-84603-432-9 ( militaryrussia.ru [PDF; accessed July 5, 2015]).
  60. ^ M1 Main Battle Tank globalsecurity.org, Section 20. Retrieved September 27, 2009.
  61. a b Defense Technology International. - December 2009, p. 14.
  62. Welt.de: USA use heavy battle tanks for the first time.
  63. ^ Numbers from Globalsecurity.org
  64. Christopher Foss: Jane's Armor & Artillery 2009-2010. P. 171.
  65. Military vehicles. Issue 3/2010, p. 28 New camouflage clothing for the Australian M1A1 AIM Abrams. Tankograd Publishing - Verlag Jochen Vollert.
  66. anao.gov.au Audit Report No. 1 2007-08 Acquisition of the ABRAMS Main Battle Tank. ( Memento of June 5, 2011 in the Internet Archive ) (PDF; 633 kB), accessed on January 1, 2012.
  67. ^ Defense Security Cooperation Agency ( Memento of February 16, 2013 in the Internet Archive ) (PDF; 59 kB), press release.
  68. a b Carl Schulze: M1A1 / M1A2 SEP Abrams TUSK. P. 7.
  69. ^ Agence France-Presse: Iraq takes delivery of American tanks. defencetalk.com, August 9, 2010, accessed June 10, 2013 .
  70. Iraqi Army receives last shipment of Abrams tanks. Army.mil, September 6, 2011, accessed June 10, 2013 .
  71. Christopher Foss: Jane's Armor & Artillery 2009-2010. P. 166
  72. 6 more tanks. Defenseindustrydaily.com, October 5, 2010, accessed June 10, 2013 .
  73. Boris Kálnoky: Turkey's tank problem in the fight against IS. welt.de, October 3, 2014, accessed on October 21, 2017 .
  74. Aziz Allilou: Morocco Purchases US-made M1A1 Abrams tanks. In: moroccoworldnews.com. Morocco World News, August 30, 2015, accessed August 27, 2018 .
  75. General Dynamics Awarded $ 358 Million for 150 M1A1 SA Abrams Tanks for Morocco. In: gd.com. General Dynamics, September 30, 2015, accessed August 27, 2018 .
  76. ^ March past PzBrig 3. Accessed January 30, 2018 .
  77. The US approved to grant 400 M1A1 Abrams to Greece
  78. USA offers Greece 400 M1 Abrams - in Greek ( Memento from February 11, 2012 in the Internet Archive )
  79. Paul-Werner Krapke: Leopard 2. His becoming and his performance. ISBN 3-8334-1425-1 , p. 199.
  80. ^ Carl Schulze: M1A1 / M1A2 SEP Abrams TUSK. P. 4.
  81. ^ The Abrams Integrated Management (AIM) Overhaul Program at fprado.com. fprado.com, accessed December 8, 2009 (English): "The Abrams Integrated Management (AIM) Overhaul Program is an innovative teaming of the prime contractor, GDLS, and Anniston Army Depot (ANAD) to refurbish the tank to a like- new condition. The AIM Overhaul is the Army's under-funded program to sustain the nearly 7,000 Abrams Tanks as part of the total recapitalization plan. AIM is funded at 135 tanks per year which translates into a 12-year rebuild cycle for the active component. "
  82. a b c d e f Carl Schulze: M1A1 / M1A2 SEP Abrams TUSK, American Special No 3009. Tankograd Publishing - Verlag Jochen Vollert
  83. M1A2 Main Battle Tank Globalsecurity.org, Sections 1–3. Retrieved August 18, 2009
  84. ^ M1A2 Main Battle Tank Globalsecurity.org, Sections 6-18. Retrieved August 18, 2009
  85. ^ M1 Grizzly Globalsecurity.org. Retrieved November 4, 2009
  86. M1 Abrams Panther II Globalsecurity.org. Retrieved November 4, 2009
  87. ^ David Doyle: M1 Abrams ABV Breacher . In: Tankograd military vehicles . No. 4 . Jochen Vollert, Erlangen 2013, p. 18-25 (English: once more into the Breach Classic Military Vehicle No. 140. Translated by Jochen Vollert).
This article was added to the list of excellent articles on December 26, 2009 in this version .