Misplaced Pages

#564435

93-516: The tank has a conventional layout similar to other Western MBTs : a driver located at the front of the hull, the fighting compartment towards the middle, and the engine compartment in the rear of the hull. The Ariete's main armament is 120 mm smoothbore gun, designed by OTO Breda , similar to the Rheinmetall L/44. The gun fires most NATO-standard rounds of the same calibre. It carries 42 rounds, 15 ready rounds are stored vertically on

186-410: A battle tank or universal tank , is a tank that fills the role of armour-protected direct fire and maneuver in many modern armies. Cold War -era development of more powerful engines, better suspension systems and lighter composite armour allowed for the design of a tank that had the firepower of a super-heavy tank , the armour protection of a heavy tank , and the mobility of a light tank , in

279-505: A "heavy" tank for assaulting fixed positions, was redesigned during the war with armour and gun upgrades to allow it to take on anti-tank roles as well, and was reclassified as a medium tank. The second half of World War II saw an increased reliance on general-purpose medium tanks, which became the bulk of the tank combat forces. Generally, these designs massed about 25–30 t (25–30 long tons; 28–33 short tons), were armed with cannons around 75 mm (3.0 in), and powered by engines in

372-439: A "hunter-killer" capability in which the commander spots and designates targets for the gunner in a 360° field of vision around the vehicle without changing his position or having to open the turret hatch for visual identification of targets. The commander's sight also has a vertical traverse from –10° to +60° from the horizontal, which allows the tank to engage low-flying airborne threats—primarily helicopters. During night fighting,

465-453: A 360º view of the tank's surroundings onto crew helmet-mounted displays or other display systems. MBTs, like previous models of tanks, move on continuous tracks , which allow a decent level of mobility over most terrain including sand and mud. They also allow tanks to climb over most obstacles. MBTs can be made water-tight, so they can even dive into shallow water (5 m (16 ft) with snorkel). However, tracks are not as fast as wheels;

558-424: A burden on tactics, training, support and maintenance. The MBT has a positive morale effect on the infantry it accompanies. It also instills fear in the opposing force who can often hear and even feel their arrival. Power-to-weight ratio Power-to-weight ratio ( PWR , also called specific power , or power-to-mass ratio ) is a calculation commonly applied to engines and mobile power sources to enable

651-403: A continuous flow of electrolyte. Flow cells typically have the fuel dissolved in the electrolyte. Power-to-weight ratios for vehicles are usually calculated using curb weight (for cars) or wet weight (for motorcycles), that is, excluding weight of the driver and any cargo. This could be slightly misleading, especially with regard to motorcycles, where the driver might weigh 1/3 to 1/2 as much as

744-406: A cutoff voltage are typically specified for a battery by its manufacturer. The output voltage falls to the cutoff voltage when the battery becomes "discharged". The nominal output voltage is always less than the open-circuit voltage produced when the battery is "charged". The temperature of a battery can affect the power it can deliver, where lower temperatures reduce power. Total energy delivered from

837-406: A digital fire-control computer, which is capable of measuring wind speed , humidity , and exterior weather conditions, combining them with the turret's angle of elevation , attitude, and the barrel's physical wear to increase accuracy. This computer is also a component of the tank's navigation system and allows for the exchange of tactical information between vehicles in a network. The Ariete has

930-406: A dual role, able to engage other armoured targets such as tanks and fortifications, and soft targets such as light vehicles and infantry. It is fixed to the turret, along with the loading and fire mechanism. Modern tanks use a sophisticated fire-control system , including rangefinders , computerized fire control, and stabilizers, which are designed to keep the cannon stable and aimed even if the hull

1023-467: A fluid, or storage in a pressure vessel . A variety of effects can be harnessed to produce thermoelectricity , thermionic emission , pyroelectricity and piezoelectricity . Electrical resistance and ferromagnetism of materials can be harnessed to generate thermoacoustic energy from an electric current. All electrochemical cell batteries deliver a changing voltage as their chemistry changes from "charged" to "discharged". A nominal output voltage and

SECTION 10

#1732783450565

1116-511: A high RPM to perform well, thus reducing the operating time between failures. Moreover, to retain a good power-to-weight ratio , the total weight of the tank had to be kept below 60 tonnes. The relatively light weight of the Ariete helped lower consumption and facilitated the transport and mobility of the MBT (especially over bridges). This was obtained partially at the expense of the thickness of

1209-401: A high level of self-protection, and which is not designed and equipped primarily to transport combat troops." Originally, most MBTs relied on steel armour to defend against various threats. As newer threats emerged, however, the defensive systems used by MBTs had to evolve to counter them. One of the first new developments was the use of explosive reactive armour (ERA), developed by Israel in

1302-563: A higher discharge current – and therefore higher power-to-weight ratio – but only with a lower energy capacity. Power-to-weight ratio for batteries is therefore less meaningful without reference to corresponding energy-to-weight ratio and cell temperature. This relationship is known as Peukert's law . Capacitors store electric charge onto two electrodes separated by an electric field semi-insulating ( dielectric ) medium. Electrostatic capacitors feature planar electrodes onto which electric charge accumulates. Electrolytic capacitors use

1395-556: A human to load. This reduces the silhouette which improves the MBT's target profile. However, with a manual loader, the rounds can be isolated within a blowout chamber, rather than a magazine within the turret, which could improve crew survivability. However, the force of a modern depleted uranium APFSDS round at the muzzle can exceed 6000 kN (a rough estimate, considering a uranium 60 cm/2 cm rod, 19g/cm , @ 1,750 m/s). Composite+reactive armour could withstand this kind of force through its deflection and deformation, but with

1488-406: A liquid electrolyte as one of the electrodes and the electric double layer effect upon the surface of the dielectric-electrolyte boundary to increase the amount of charge stored per unit volume. Electric double-layer capacitors extend both electrodes with a nanoporous material such as activated carbon to significantly increase the surface area upon which electric charge can accumulate, reducing

1581-678: A new universal tank was rendered unnecessary. The Centurion, entering service just as World War II finished, was a multi-role tank that subsequently formed the main armoured element of the British Army of the Rhine , the armed forces of the British Empire and Commonwealth forces, and subsequently many other nations through exports, whose cost was met largely by the US. The introduction of the 84 mm (3.3 in) 20-pounder gun in 1948 gave

1674-589: A package with the weight of a medium tank . The first designated MBT was the British Chieftain tank , which during its development in the 1950s was re-designed as an MBT. Throughout the 1960s and 1970s, the MBT replaced almost all other types of tanks, leaving only some specialist roles to be filled by lighter designs or other types of armoured fighting vehicles . Main battle tanks are a key component of modern armies. Modern MBTs seldom operate alone, as they are organized into armoured units that include

1767-531: A power-to-weight ratio of 0.65 kW/kg (0.40 hp/lb). Examples of high power-to-weight ratios can often be found in turbines. This is because of their ability to operate at very high speeds. For example, the Space Shuttle 's main engines used turbopumps (machines consisting of a pump driven by a turbine engine) to feed the propellants (liquid oxygen and liquid hydrogen ) into the engine's combustion chamber. The original liquid hydrogen turbopump

1860-535: A second hit in the same area, an armour breach is inevitable. As such, the speed of follow up shots is crucial within tank to tank combat. As secondary weapons, an MBT usually uses between two and four machine guns to engage infantry and light vehicles. Many MBTs mount one heavy caliber anti-aircraft machine gun (AAMG), usually of .50 caliber (like the M2 Browning or DShK ), which can be used against helicopters and low flying aircraft. However, their effectiveness

1953-463: A single charge cycle is affected by both the battery temperature and the power it delivers. If the temperature lowers or the power demand increases, the total energy delivered at the point of "discharge" is also reduced. Battery discharge profiles are often described in terms of a factor of battery capacity . For example, a battery with a nominal capacity quoted in ampere-hours (Ah) at a C/10 rated discharge current (derived in amperes) may safely provide

SECTION 20

#1732783450565

2046-619: A target and thereby enhance the first-round hit probability. The United States's experience in the Vietnam War contributed to the idea among army leadership that the role of the main battle tank could be fulfilled by attack helicopters . During the Vietnam War, helicopters and missiles competed with MBTs for research money. Though the Persian Gulf War reaffirmed the role of main battle tanks, MBTs were outperformed by

2139-507: A top cruising speed of 65 km/h and a 0–32 km/h acceleration in 6 seconds. The computer-controlled transmission allows it to climb grades rated up to 60%, and can ford waterways of up to 1.25 m on-the-fly. The entire engine and transmission assembly can be replaced in under 1 hour. The Ariete's independent suspension system consists of 14 torsion bars with suspension arms, 10 hydraulic shock absorbers (installed on roadwheels numbers 1, 2, 3, 6 and 7), and 14 friction dampers. During

2232-667: A train. As the coefficient of friction between steel wheels and rails seldom exceeds 0.25 in most cases, improving a locomotive's power-to-weight ratio is often counterproductive. However, the choice of power transmission system, such as variable-frequency drive versus direct-current drive , may support a higher power-to-weight ratio by better managing propulsion power. Most vehicles are designed to meet passenger comfort and cargo carrying requirements. Vehicle designs trade off power-to-weight ratio to increase comfort, cargo space, fuel economy , emissions control , energy security and endurance. Reduced drag and lower rolling resistance in

2325-458: A trend towards heavier weight and greater firepower during World War II; speed was not a substitute for armour and firepower. An increasing variety of anti-tank weapons and the perceived threat of a nuclear war prioritized the need for additional armour. The additional armour prompted the design of even more powerful guns. The main battle tank thus took on the role the British had once called

2418-522: A vehicle design can facilitate increased cargo space without increase in the (zero cargo) power-to-weight ratio. This increases the role flexibility of the vehicle. Energy security considerations can trade off power (typically decreased) and weight (typically increased), and therefore power-to-weight ratio, for fuel flexibility or drive-train hybridisation . Some utility and practical vehicle variants such as hot hatches and sports-utility vehicles reconfigure power (typically increased) and weight to provide

2511-534: A world of shaped charge weapons, and new designs rapidly emerged from most armed forces. The Quebec conference in 1957 between the US, UK and Canada identified the MBT as the route for development rather than separate medium and heavy tanks. The concept of the medium tank gradually evolved into the MBT in the 1960s, as it was realized that medium tanks could carry guns (such as the American 90 mm (3.5 in), Soviet 100 mm (3.9 in), and especially

2604-402: Is an important vehicle characteristic that affects the acceleration of sports vehicles. Propeller aircraft depend on high power-to-weight ratios to generate sufficient thrust to achieve sustained flight, and then for speed. Jet aircraft produce thrust directly . Power-to-weight ratio is important in cycling, since it determines acceleration and the speed during hill climbs . Since

2697-435: Is considered one of the fastest MBTs in existence. The MBT is often cumbersome in traffic and frequently obstructs the normal flow of traffic. The tracks can damage some roads after repeated use. Many structures like bridges do not have the load capacity to support an MBT. In the fast pace of combat, it is often impossible to test the sturdiness of these structures. Though appreciated for its excellent off-road characteristics,

2790-417: Is conversely usually lower. Fuel cells and flow cells , although perhaps using similar chemistry to batteries, do not contain the energy storage medium or fuel . With a continuous flow of fuel and oxidant, available fuel cells and flow cells continue to convert the energy storage medium into electric energy and waste products. Fuel cells distinctly contain a fixed electrolyte whereas flow cells also require

2883-427: Is defined as the power generated by the engine(s) divided by the mass. In this context, the term "weight" can be considered a misnomer, as it colloquially refers to mass. In a zero-gravity (weightless) environment, the power-to-weight ratio would not be considered infinite. A typical turbocharged V8 diesel engine might have an engine power of 250 kW (340 hp) and a mass of 380 kg (840 lb), giving it

Ariete - Misplaced Pages Continue

2976-421: Is given by F ( t ) ⋅ v ( t ) = m a ( t ) ⋅ v ( t ) = τ ( t ) ⋅ ω ( t ) {\displaystyle \mathbf {F} (t)\cdot \mathbf {v} (t)=m\mathbf {a} (t)\cdot \mathbf {v} (t)=\mathbf {\tau } (t)\cdot \mathbf {\omega } (t)} . where: In propulsion , power

3069-456: Is limited in comparison to dedicated anti-aircraft artillery. The tank's machine guns are usually equipped with between 500 and 3,000 rounds each. Performing situational awareness and communicating is one of four primary MBT functions. For situational awareness, the crew can use a circular review system combining augmented reality and artificial Intelligence technologies. These systems use several externally mounted video sensors to transfer

3162-499: Is only delivered if the powerplant is in motion, and is transmitted to cause the body to be in motion. It is typically assumed here that mechanical transmission allows the powerplant to operate at peak output power. This assumption allows engine tuning to trade power band width and engine mass for transmission complexity and mass. Electric motors do not suffer from this tradeoff, instead trading their high torque for traction at low speed. The power advantage or power-to-weight ratio

3255-474: Is performed in high-intensity conflicts where reconnaissance by light vehicles would be insufficient due to the necessity to "fight" for information. In asymmetric warfare, main battle tanks are deployed in small, highly concentrated units. MBTs fire only at targets at close range and instead rely on external support such as unmanned aircraft for long range combat. Main battle tanks have significantly varied characteristics. Procuring too many varieties can place

3348-524: Is reserved for ammunition. External space enhances independence of logistics and can accommodate extra fuel and some personal equipment of the crew. The Israeli Merkava can accommodate crew members displaced from a destroyed vehicle in its ammunition compartment. Emphasis is placed on selecting and training main battle tank crew members. The crew must perform their tasks faultlessly and harmoniously so commanders select teams taking into consideration personalities and talents. The main battle tank fulfills

3441-405: Is similar in size to an automobile engine (weighing approximately 352 kilograms (775 lb)) and produces 72,000 hp (54 MW) for a power-to-weight ratio of 153 kW/kg (93 hp/lb). In classical mechanics , instantaneous power is the limiting value of the average work done per unit time as the time interval Δ t approaches zero (i.e. the derivative with respect to time of

3534-405: Is then where: The useful power of an engine with shaft power output can be calculated using a dynamometer to measure torque and rotational speed , with maximum power reached when torque multiplied by rotational speed is a maximum. For jet engines the useful power is equal to the flight speed of the aircraft multiplied by the force, known as net thrust, required to make it go at that speed. It

3627-574: Is turning or shaking, making it easier for the operators to fire on the move and/or against moving targets. Gun-missile systems are complicated and have been particularly unsatisfactory to the United States who abandoned gun-missile projects such as the M60A2 and MBT-70 , but have been diligently developed by the Soviet Union, who even retrofitted them to T-55 tanks, in an effort to double

3720-455: Is used when calculating propulsive efficiency . Thermal energy is made up from molecular kinetic energy and latent phase energy. Heat engines are able to convert thermal energy in the form of a temperature gradient between a hot source and a cold sink into other desirable mechanical work . Heat pumps take mechanical work to regenerate thermal energy in a temperature gradient. Standard definitions should be used when interpreting how

3813-487: The Cromwell tank , combined with efficiency savings elsewhere in the design, almost doubled the horsepower for cruiser tanks. This led to speculation of a "Universal Tank", able to take on the roles of both a cruiser and an infantry tank by combining heavy armour and manoeuvrability. Field Marshal Bernard Montgomery is acknowledged as the main advocate of the British universal tank concept as early as 1943, according to

Ariete - Misplaced Pages Continue

3906-655: The Second Battle of Fallujah the United States Marines brought in two extra companies of M1s. Britain deployed its Challenger 2 tanks to support its operations in southern Iraq. Advanced armour has reduced crew fatalities but has not improved vehicle survivability. Small unmanned turrets on top of the cupolas called remote controlled weapon stations armed with machine guns or mortars provide improved defence and enhance crew survivability. Experimental tanks with unmanned turrets locate crew members in

3999-532: The T-72 . The United States Army used 1,100 M1 Abrams in the course of the Iraq War . They proved to have an unexpectedly high vulnerability to improvised explosive devices . A relatively new type of remotely detonated mine, the explosively formed penetrator , was used with some success against American armoured vehicles. However, with upgrades to their rear armour, M1s proved to be valuable in urban combat; at

4092-543: The attack helicopter . Other strategists considered that the MBT was entirely obsolete in light of the efficacy and speed with which coalition forces neutralized Iraqi armour. In asymmetric warfare , threats such as improvised explosive devices and mines have proven effective against MBTs. In response, nations that face asymmetric warfare, such as Israel, are reducing the size of their tank fleet and procuring more advanced models. Conversely, some insurgent groups like Hezbollah themselves operate main battle tanks, such as

4185-586: The "universal tank", exemplified by the Centurion, filling almost all battlefield roles. Typical main battle tanks were as well armed as any other vehicle on the battlefield, highly mobile, and well armoured. Yet they were cheap enough to be built in large numbers. The first Soviet main battle tank was the T-64A (the T-54/55 and T-62 were considered "medium" tanks) and the first American nomenclature-designated MBT

4278-609: The 400–500 hp (300–370 kW) range. Notable examples include the Soviet T-34 (the most-produced tank at that time) and the US M4 Sherman . Late war tank development placed increased emphasis on armour, armament, and anti-tank capabilities for medium tanks: Britain had continued on the path of parallel development of cruiser tanks and infantry tanks. Development of the Rolls-Royce Meteor engine for

4371-504: The Brazilian Army, limits contenders to a maximum weight of 50 tonnes, which rules out the Ariete unless changes were made to Brazilian technical requirements. Each tank battalion fields three tank companies with thirteen Ariete each and two Ariete for the battalion commander and the deputy commander. Background: History of the tank , Tank classification Main battle tank A main battle tank ( MBT ), also known as

4464-627: The British L7 105 mm (4.1 in) ) that could penetrate any practical level of armour then existing at long range. Also, the heaviest tanks were unable to use most existing bridges. The World War II concept of heavy tanks , armed with the most powerful guns and heaviest armour, became obsolete because the large tanks were too expensive and just as vulnerable to damage by mines, bombs, rockets, and artillery. Likewise, World War II had shown that lightly armed and armoured tanks were of limited value in most roles. Even reconnaissance vehicles had shown

4557-761: The C1 Ariete during the future major revisions. The Ariete AMV is a mid life update (Ammodernamento di Mezza Vita) of the Ariete for 125 units and includes: CIO-Oto Melara planned to offer the opening of a production line in Brazil at its Sete Lagoas plant, where the LMV is already produced and the Centauro II will be produced for the Brazilian Army. However, the Army Strategic Program Armored Forces , which would provide 65 MBTs for

4650-546: The French Leclerc , or the Russian/Ukrainian T-64 , T-72 , T-80 , T-84 , T-90 , and T-14 and, for this reason, the crew can be reduced to 3 members. MBTs with an autoloader require one less crew member and the autoloader requires less space than its human counterpart, allowing for a reduction in turret size. Further, an autoloader can be designed to handle rounds which would be too difficult for

4743-551: The French Renault FT ; these were light tanks or tankettes . Many late-war and inter-war tank designs diverged from these according to new, and mostly untried, concepts for future tank roles and tactics. Each nation tended to create its own list of tank classes with different intended roles, such as "cavalry tanks", "breakthrough tanks", "fast tanks", and "assault tanks". The British maintained cruiser tanks that in order to achieve high speed and hence manoeuvrability in

SECTION 50

#1732783450565

4836-422: The MBT can become immobilized in muddy conditions. The high cost of MBTs can be attributed in part to the high-performance engine-transmission system and to the fire control system. Also, propulsion systems are not produced in high enough quantities to take advantage of economies of scale . Crew fatigue limits the operational range of MBTs in combat. Reducing the crew to three and relocating all crewmembers from

4929-413: The Soviet Union's fighting capability. The Soviet Union made novel advancements to the weapon systems including mechanical autoloaders and anti-tank guided missiles . Autoloaders were introduced to replace the human loader, permitting the turret to be reduced in size, making the tank smaller and less visible as a target, while missile systems were added to extend the range at which a vehicle could engage

5022-636: The armour that, only partially compensated by the good ballistic shape of the vehicle, raised some doubt about its ability to survive in the harshest environments. As an improvement, Iveco developed a new version of the MTCA engine. The stroke was lengthened, increasing displacement to 30 litres, with a new common rail direct fuel injection system along a new double turbocharger, increasing power output to 1,200 kW (1,600 hp) at 1,800 rpm (with an electronically reduced torque of 5,500 N·m, maintained from 1,100 to 1,800 rpm to reduce damage to

5115-411: The attack carried less armour, and infantry tanks which operating at infantryman pace could carry more armour. After years of isolated and divergent development, the various interwar tank concepts were finally tested with the start of World War II . In the chaos of blitzkrieg , tanks designed for a single role often found themselves forced into battlefield situations they were ill-suited for. During

5208-480: The centre and radial of a gravitational field by an onboard powerplant , then the associated kinetic energy is where: The work–energy principle states that the work done to the object over a period of time is equal to the difference in its total energy over that period of time, so the rate at which work is done is equal to the rate of change of the kinetic energy (in the absence of potential energy changes). The work done from time t to time t + Δ t along

5301-667: The commander and gunner both share the thermal sight which is able to resolve a 2.3×x2.3 m target from a distance of 1,500 m. The Ariete's armour is a steel and composite blend, the turret front shape is similar to the British Challenger 1 and the American M1 Abrams . The Ariete features two side-mounted, electronically fired GALIX 80mm grenade launchers. Each launcher consists of four 80 mm barrels which can be intermixed with either smoke or chaff grenades. The smoke grenades are capable of shrouding

5394-416: The comparison of one unit or design to another. Power-to-weight ratio is a measurement of actual performance of any engine or power source. It is also used as a measurement of performance of a vehicle as a whole, with the engine's power output being divided by the weight (or mass ) of the vehicle, to give a metric that is independent of the vehicle's size. Power-to-weight is often quoted by manufacturers at

5487-444: The detonation of ERA blocks creates a hazard to any supporting infantry near the tank. Despite this drawback, it is still employed on many Russian MBTs, the latest generation Kontakt-5 being capable of defeating both high-explosive anti-tank (HEAT) and kinetic energy penetrator threats. The Soviets also developed Active Protection Systems (APS) designed to more actively neutralize hostile projectiles before they could even strike

5580-458: The dielectric medium to nanopores and a very thin high permittivity separator. While capacitors tend not to be as temperature sensitive as batteries, they are significantly capacity constrained and without the strength of chemical bonds suffer from self-discharge. Power-to-weight ratio of capacitors is usually higher than batteries because charge transport units within the cell are smaller (electrons rather than ions), however energy-to-weight ratio

5673-520: The early 1980s to defend against the shaped-charge warheads of modern anti-tank guided missiles and other such high-explosive anti-tank (HEAT) projectiles. This technology was subsequently adopted and expanded upon by the United States and the Soviet Union. MBT armour is concentrated at the front of the tank, where it is layered up to 33 centimetres (13 in) thick. Missiles are cheap and cost-effective anti-tank weapons. ERA can be quickly added to vehicles to increase their survivability. However,

SECTION 60

#1732783450565

5766-690: The early 1990s and 2000s; surviving numerous impacts from 1950s, 1960s, and 1970s era rocket-propelled grenades with negligible damage. It is much less efficient against later models of RPGs. For example, the RPG-29 from the 1980s is able to penetrate the frontal hull armour of the Challenger 2. Main battle tanks are equipped with a main gun and at least one machine gun . MBT main guns are generally between 100 mm (3.9 in) and 125 mm (4.9 in) caliber, and can fire both anti-armour and, more recently, anti-personnel rounds. The cannon serves

5859-513: The early 2000s, the Italian Army was interested in developing a new version of Ariete (C2 Ariete or Ariete Mk. 2 designations were considered) which would enter service over the following years with the planned acquisition of 300 units. Budget limitations drastically reduced the number of improved Ariete (order reduced to 200) and eventually caused the subsequent cancellation of the program. The planned improvements were therefore to be applied to

5952-400: The effect of protecting the vehicle's occupants from nuclear explosion radiation). By the late 1970s, MBTs were manufactured by China, France, West Germany, Britain, India, Italy, Japan, the Soviet Union, Sweden, Switzerland, and the United States. The Soviet Union's war doctrine depended heavily on the main battle tank. Any weapon advancement making the MBT obsolete could have devastated

6045-988: The effective range of the vehicle's fire. The MBT's role could be compromised because of the increasing distances involved and the increased reliance on indirect fire . The tank gun is still useful in urban combat for precisely delivering powerful fire while minimizing collateral damage. High-explosive anti-tank (HEAT), and some form of high velocity kinetic energy penetrator , such as armour-piercing fin-stabilized discarding sabot (APFSDS) rounds are carried for anti-armour purposes. Anti-personnel rounds such as high explosive or high explosive fragmentation have dual purpose. Less common rounds are Beehive anti-personnel rounds , and high-explosive squash head (HESH) rounds used for both anti-armour and bunker busting. Usually, an MBT carries 30–50 rounds of ammunition for its main tank gun , usually split between HE, HEAT, and KEP rounds. Some MBTs may also carry smoke or white phosphorus rounds. Some MBTs are equipped with an autoloader , such as

6138-419: The era. Later came British Chobham armour . This composite armour used layers of ceramics and other materials to help attenuate the effects of HEAT munitions. Another threat came by way of the widespread use of helicopters in battle. Before the advent of helicopters, armour was heavily concentrated to the front of the tank. This new threat caused designs to distribute armour on all sides of the tank (also having

6231-657: The first years of adoption, the Ariete MBT showed some deficiencies regarding the powerplant. While the original V12 1,250 hp FIAT-Iveco MTCA (Modular Turbo-Charged Aftercooler) was a coupling of two of the V6 engines used by several Italian Army vehicles such as the B1 Centauro tank destroyer and the Dardo IFV , it produced less power than the most advanced contemporary western designs. The Ariete's engine had to run at

6324-465: The heavily armoured hull, improving survivability and reducing the vehicle's profile. Technology is reducing the weight and size of the modern MBT. A British military document from 2001 indicated that the British Army would not procure a replacement for the Challenger 2 because of a lack of conventional warfare threats in the foreseeable future. The obsolescence of the tank has been asserted, but

6417-617: The history of the late 20th and early 21st century suggested that MBTs were still necessary. During the Russian invasion of Ukraine , Western and Russian MBTs saw large-scale combat in large numbers. The Organization for Security and Co-operation in Europe defines a main battle tank as "a self-propelled armoured fighting vehicle, capable of heavy firepower, primarily of a high muzzle velocity direct fire main gun necessary to engage armoured and other targets, with high cross-country mobility, with

6510-486: The left side of the main gun breech. The other 27 are stowed in a hull rack to the left of the driver's station. The gun barrel has a thermal insulating sleeve and a fume extractor; it is fully stabilized in both azimuth and elevation by an electro-hydraulic drive system. Secondary armament consists of a 7.62 mm MG 42/59 coaxial machine gun operated by the tank gunner or commander and an additional 7.62 mm MG 42/59 configured as an anti-aircraft weapon operated by

6603-568: The limits of mechanical technology. This limited the specific battlefield capabilities any one tank design could be expected to fulfill. A design might have good speed, armour, or firepower, but not all three together. Facing the deadlock of trench warfare , the first tank designs focused on crossing wide trenches, requiring very long and large vehicles, such as the British Mark I tank and successors; these became known as heavy tanks . Tanks that focused on other combat roles were smaller, like

6696-431: The main-gun loader from his hatch. The tank's advanced fire-control system, manufactured by Galileo Avionica, is designated OG14L3 TURMS, and includes day and night panoramic capability for the commander's SP-T-694 primary sight (developed collaboratively by SFIM/Galileo), a stabilized platform including a thermal gunner's sight and a laser rangefinder to increase accuracy and expedite target detection and targeting, and

6789-439: The maximum speed of a tank is about 65 km/h (40 mph) . The extreme weight of vehicles of this type 40–70 t (39–69 long tons; 44–77 short tons) also limits their speed. They are usually equipped with a 1,200–1,500 hp (890–1,120 kW) engine (more than 25,000 cc (1,526 cu in)), with an operational range near 500 km (310 mi). The German Army has prioritized mobility in its Leopard 2 which

6882-518: The number of aircraft available. Military planners anticipate that the airlift capability for MBTs will not improve in the future. To date, no helicopter has the capability to lift MBTs. Rail and road are heavily used to move MBTs nearer to the battle, ready to fight in prime condition. Where well maintained roads allow it, wheeled tank transporters can be used. The task of resupply is usually accomplished with large trucks. Main battle tanks have internal and external storage space. Internal space

6975-422: The path C is defined as the line integral ∫ C F ⋅ d x = ∫ t t + Δ t F ⋅ v ( t ) d t {\displaystyle \int _{C}\mathbf {F} \cdot d\mathbf {x} =\int _{t}^{t+\Delta t}\mathbf {F} \cdot \mathbf {v} (t)dt} , so the fundamental theorem of calculus has that power

7068-451: The peak value, but the actual value may vary in use and variations will affect performance. The inverse of power-to-weight, weight-to-power ratio (power loading) is a calculation commonly applied to aircraft, cars, and vehicles in general, to enable the comparison of one vehicle's performance to another. Power-to-weight ratio is equal to thrust per unit mass multiplied by the velocity of any vehicle. The power-to-weight ratio (specific power)

7161-442: The perception of sports car like performance or for other psychological benefit . Increased engine performance is a consideration, but also other features associated with luxury vehicles . Longitudinal engines are common. Bodies vary from hot hatches , sedans (saloons) , coupés , convertibles and roadsters . Mid-range dual-sport and cruiser motorcycles tend to have similar power-to-weight ratios. Power-to-weight ratio

7254-701: The propulsive power of a jet or rocket engine is transferred to its vehicle. An electric motor uses electrical energy to provide mechanical work , usually through the interaction of a magnetic field and current-carrying conductors . By the interaction of mechanical work on an electrical conductor in a magnetic field, electrical energy can be generated . Fluids (liquid and gas) can be used to transmit and/or store energy using pressure and other fluid properties. Hydraulic (liquid) and pneumatic (gas) engines convert fluid pressure into other desirable mechanical or electrical work . Fluid pumps convert mechanical or electrical work into movement or pressure changes of

7347-479: The rest of its armament, can also intercept aircraft and missiles. MBTs can also be protected from radar detection by incorporating stealth technology . The T-14 Armata has a turret designed to be harder to detect with radars and thermal sights. Advanced camouflage, like the Russian Nakidka , will also reduce the radar and thermal signatures of a MBT. Other defensive developments focused on improving

7440-476: The role the British had once called the "universal tank", filling almost all battlefield roles. They were originally designed in the Cold War to combat other MBTs. The modern light tank supplements the MBT in expeditionary roles and situations where all major threats have been neutralized and excess weight in armour and armament would only hinder mobility and cost more money to operate. Reconnaissance by MBTs

7533-595: The strength of the armour itself; one of the notable advancements coming from the British with the development of Chobham armour in the 1970s. It was first employed on the American M1 Abrams and later the British Challenger 1 . Chobham armour uses a lattice of composite and ceramic materials along with metal alloys to defeat incoming threats, and proved highly effective in the conflicts in Iraq in

7626-408: The support of infantry , who may accompany the tanks in infantry fighting vehicles . They are also often supported by surveillance or ground-attack aircraft . The average weight of MBTs varies from country to country. The average weight of Western MBTs is usually greater than that of Russian or Chinese MBTs. During World War I , combining tracks, armour, and guns into a functional vehicle pushed

7719-437: The tank a significant advantage over other tanks of the era, paving the way for a new tank classification, the main battle tank, which gradually superseded previous weight and armament classes. A surplus of effective WWII-era designs in other forces, notably the US and the Soviet Union, led to slower introductions of similar designs on their part. By the early 1950s, these designs were clearly no longer competitive, especially in

7812-463: The tank from visual or thermal detection, while the chaff grenades disperse the tank's radar cross section . The tank is fully NBC protected . The Ariete is powered by a 25.8-litre Fiat-Iveco MTCA turbo-diesel V12 rated at 937 kW (1,257 hp) at 2,300 rpm, with a maximum torque of 4,615 N⋅m (3,404 lbf⋅ft) at 1,600 rpm driving through a ZF LSG3000 automatic transmission , with four forward gears and two reverse, allowing for

7905-670: The tank, namely the Shtora and Arena systems. The United States has also adopted similar technologies in the form of the Missile Countermeasure Device and as part of the Tank Urban Survival Kit used on M1 Abrams tanks serving in Iraq. The latest Russian MBT, according to many forum members the T-14 Armata , incorporates an AESA radar as part of its Afghanit APS and in conjunction with

7998-415: The transmission) and further reducing fuel consumption. The new engine had to be adopted during the first general revision of the existing vehicles, but seems to have been blocked by technical and financial problems. As for the armour, Oto Melara developed two different sets (with different thickness levels, depending upon mission nature) of adjunctive armour, shown for the first time at Eurosatory 2002. In

8091-409: The turret to the hull could provide time to sleep for one off-shift crewmember located in the rear of the hull. In this scenario, crewmembers would rotate shifts regularly and all would require cross-training on all vehicle job functions. Cargo aircraft are instrumental to the timely deployment of MBTs. The absence of sufficient numbers of strategic airlift assets can limit the rate of MBT deployments to

8184-516: The vehicle itself. In the sport of competitive cycling athlete's performance is increasingly being expressed in VAMs and thus as a power-to-weight ratio in W/kg. This can be measured through the use of a bicycle powermeter or calculated from measuring incline of a road climb and the rider's time to ascend it. A locomotive generally must be heavy in order to develop enough adhesion on the rails to start

8277-487: The velocity, it experiences half the acceleration, all else being equal. If the work to be done is rectilinear motion of a body with constant mass m {\displaystyle m\;} , whose center of mass is to be accelerated along a (possibly non-straight) line to a speed | v ( t ) | {\displaystyle |\mathbf {v} (t)|\;} and angle ϕ {\displaystyle \phi \;} with respect to

8370-400: The war, limited-role tank designs tended to be replaced by more general-purpose designs, enabled by improving tank technology. Tank classes became mostly based on weight (and the corresponding transport and logistical needs). This led to new definitions of heavy and light tank classes, with medium tanks covering the balance of those between. The German Panzer IV tank, designed before the war as

8463-507: The work done). The typically used metric unit of the power-to-weight ratio is W kg {\displaystyle {\tfrac {\text{W}}{\text{kg}}}\;} which equals m 2 s 3 {\displaystyle {\tfrac {{\text{m}}^{2}}{{\text{s}}^{3}}}\;} . This fact allows one to express the power-to-weight ratio purely by SI base units . A vehicle's power-to-weight ratio equals its acceleration times its velocity; so at twice

8556-525: The writings of Giffard Le Quesne Martel , but little progress was made beyond development of the basic Cromwell cruiser tank that eventually led to the Centurion . The Centurion, at the time designated "heavy cruiser" and later "medium gun tank" was designed for mobility and firepower at the expense of armour , but more engine power permitted more armour protection, so the Centurion could also operate as an infantry tank , doing so well that development of

8649-577: Was the M60 tank . Anti-tank weapons rapidly outpaced armour developments. By the 1960s, anti-tank rounds could penetrate a meter of steel so as to make the application of traditional rolled homogeneous armour unpragmatic. The first solution to this problem was the composite armor of Soviet T-64 tank, which included steel-glass-reinforced textolite-steel sandwich in heavily sloped glacis plates, and steel turret with aluminum inserts, which helped to resist both high-explosive anti-tank (HEAT) and APDS shells of

#564435