Israel's Merkava Mark 2 Battle Tank

Israel’s Merkava Mark 2 Battle Tank by Richard M. Ogorkiewicz The appearance of any new battle tank is always an event of considerable professional interest. And it is of even greater interest when the new tank differs in many important respects from others. This applies very much to the Merkava Mark 2, the new version of Israel’s unconventional battle tank which is coming into service with the Israel Defense Forces and which the writer had the privilege of examining recently. The Mark 2 version of the Merkava, like the Mark 1, was developed by a team of Israel Defence Force (IDF) officers headed by Major GeneralIsrael Tal. General Tal has, in fact, led the development of the Merkava from its inception in 1970 and has brought to this task considerable personal experience. He had been commander of the IDF Armored Corps and of one of the three Israeli columns on the Sinai Front during the Six Day War of 1967. He is also an accomplished tank gunner, having personally knocked out targets at a range of several kilometers with a 105-mm tank gun during some particularly critical clashes on Israel’s borders. The personal experience of General Tal and that of his team has been augmented by detailed analyses of the hits sustained by Israeli and opposing tanks during the Arab-Israeli wars. These analyses now cover a total of several thousand cases and form a fund of knowledge of what happens to tanks under fire which is at once more extensive and more up-to-date than that possessed anywhere else in the world. All the experience and analyses led General Tal to conclude that the Merkava could and should provide a high degree of survivability. In keeping with this, he also opted for a high degree of battlefield, rather than strategic, mobility. At the same time he redefined survivability in terms of the two most vulner-november-december 1985 39

With turret set back on front-engined hull, Merkava has little gun tube overhang. able components of a tank its crew and its ammunition. In other words, General Tal and his team recognized that a high degree of survivability could not be achieved for the whole of a tank but that a high degree of protection could be provided for its crew and ammunition. To achieve this, General Tal decided to use as many of the other components of the tank as possible to protect the crew compartment and to adopt various unconventional design features. Front Engine Location The most obvious of the various departures from convention in the design of the Merkava is the location of the engine compartment at the front of the hull. This was adopted so that the engine and the transmission could contribute to the protection of the crew from the most likely hits, that is, hits on the front of the tank. The engine-transmission assembly is itself protected by a thick cast armor nose and, spaced behind it, an armor bulkhead. The space between the nose and the bulkhead is occupied by a fuel tank, which contributes to stopping shaped-charge jets, and the Mark 2 also cames in it special armor. There is also an armor plate bulkhead behind the engine. This means that the crew is protected from the front by three spaced layers of steel armor, a layer of special armor, and the engine-transmission assembly, as well as a fuel tank. All of this adds up to give the crew of the Mark 2 a remarkably high level of frontal protection. The top of the engine compartment is covered by a large steel casting which forms part of the well-sloped hull glacis and which can be lifted off for power pack replacement. The casting can only be lifted with a crane, but this does not create any additional maintenance problems since a crane is needed to lift the power pack. For routine maintenance, the engine can be reached by swinging open a small, hinged part of the glacis, which can be done manually. A unique and very commendable feature of the glacis is that it extends up above the level of the turret ring. In consequence, it protects the joint between the turret and the hull, which is generally a vulnerable point in turreted tanks. The concept of protecting the crew compartment by mechanical components as well as more than one layer of armor has been carried around to the sides of the tank. As part of it, the conventional torsion bar suspension was rejected in favor of an externally-mounted coil spring suspension. The suspension has been compared with the bogie-type suspension of the British Centurion and Chieftain tanks, but in spite of a superficial resemblance, it is basically different. In fact, it is not a bogie-type suspension with interconnecting horizontal springs, but a n independent suspension with vertical coil springs. The springs, together with the suspension mountings of ballistic steel, form an almost continuous protective layer outside the hull side armor, any gaps being covered by additional armor plates. Further protection at the sides is provided by steel skirts, backed on the Merkava Mark 2 by special armor. In contrast to other contemporary tanks, the special armor-backed skirts cover the whole of the sides of the tank and not merely their front portions. As a result, the sides of the Mark 2 hull are better protected than those of any other tank. In contrast to other tanks, the rear of the Merkava’s hull is also well-protected. Ths is done with two layers of armor; the space between them is filled on one side with batteries and on the other with a collective NBC protection system. There is also exceptionally good protection against mine blast. This is due not only to the bottom of the 40 november-december 1 985

Major General Israel Tal. who led the team that designed Merkava. hull being relatively thick along the whole of its length but also to an inner layer of spaced armor, which forms the floor plate. Rear Hull Compartment The location of the engine at the front made it possible to locate most of the ammunition at the rear of the hull, where it is least vulnerable to direct fire. To reduce the vulnerability of the ammunition to mine attack, one of the seven cells among which the fuel is distributed for greater safety has been located under the ammunition stowage area. From above, the ammunition is protected not only by the hull roof armor but also by a large tank of drinking water which is located under the roof. Under most circumstances, the ammunition is also shielded from top attack by the turret bustle and the large stowage basket attached to it. All the ammunition is stowed in special containers of fiberglass lined with an insulating material which can protect it for relatively long periods of time from the heat of any fire. In addition, the containers act as spa11 shields if the armor of the tank is perforated. Apart from reducing the vulnerability of the ammunition, the front engine location made it possible to provide a hatch in the rear of the hull. This hatch, together with a passage left between the stacks of ammunition containers, provides the crew of the Merkava with a safer alternative to the traditional way of entering or leaving tanks through the top, which is particularly valuable if they ever have to evacuate the tank under fire. Another important benefit of the rear hatch is that the Merkava can be reloaded through it much more easily than more conventional tanks. The ammunition containers are removable, and this Takes it possible to use the ammunition stowage space for other purposes. For instance, if the ammunition containers are removed, the rear of the hull can be occupied by a command team. Alternatively, it can be used to carry four stretcher cases or up to 10 infantrymen. The fact that the Merkava can carry infantrymen has been misinterpreted by many people, including several contributors to ARMOR, who have wrongly assumed it to be some kind of tank-cum-infantry carrier. What is more, a number of people have cited the Merkava in support of an argument for the development of hybrid tank-infantry vehicles. Those who have done this not only misunderstand the design of the Merkava, but seem to have no idea of the monstrous size of any tank which would carry not only a major caliber gun and a full load of ammunition, but also a squad of infantry. Moreover, they ignore the obvious fact that infantrymen, carried in any vehicle which fulfills its main purpose and engages in combat with its armament, can contribute nothing to the tank except casualties. hybrid vehicle of any kind but a tank. It can only carry infantrymen at the expense of part or most of its ammunition, which is only justifiable and done in very special circumstances. Thus, under normal circumstances, the Merkava only cames its regular crew of four, and its rear compartment is filled with ammunition. Low Frontal Area Turret Like the hull, the turret of the Merkava is unconventional. In particular, much of it consists of two spaced layers of cast steel armor. In addition, the turret of the Mark 2 has special armor at the front and sides. The turret also has an unusually small frontal area, which reduces its chances of being hit. This is particularly true when the Merkava is in defilade, when the total exposed area of the turret is only one-half of that of other contem-november-december 1985 41

Rear-quarter view shows rear door. deep bustle tack, and chain link “curtain” designed to pm-ignite shaped charge warheads. porary tanks’ turrets. To achieve such a low frontal area, the gun trunnions have been moved closer to the breech. This made it possible to reduce the height of the turret without reducing the depression of the gun beyond 8 degrees, which has been found adequate even in the hilly terrain of southern Lebanon. It also made it possible to locate the loader toward the rear and center of the gun, which reduced the width of the turret on his side. Another feature contributing to the low frontal area of the turret is the highly commendable absence of any projections above the turret roof, except for the heads of the periscopes and the mountings of the machine guns. Because of the front engine compartment, the turret is set well back. As a result, the gun protrudes far less beyond the front of the hull than in other tanks, which reduces the risk of it digging in and being damaged during the crossing of ditches and similar obstacles. The protrusion of the gun is actually so small that the turret does not have to be traversed to the rear for ease of non-tactical movement but can remain in its natural position, with the gun pointing forward. 42 november-december 1985 Except for its mounting, the 105- mm gun of the Merkava is virtually the same as the U S . M68. But it is made entirely by Israel Military Industries and is fitted with a highly effective, Israeli-developed, thermal sleeve. In addition to the usual coaxial machine gun, there are two others, mounted externally above the commander’s and loader’s hatches. All three are 7.62-mm caliber, the IDF having very wisely rejected the use by tank commanders of caliber .50 machine guns, which are more powerful than necessary against personnel and not powerful enough against most other targets, and which unnecessarily complicate ammunition supply and stowage. On the other hand, the experience of the Yom Kippur War of 1973 led the IDF to introduce another and very different weapon in its tanks, namely a 60-mm mortar. When first adopted for existing tanks, the 60-mm mortars had to be mounted externally, but the Merkava Mark 2 has its 60-mm mortar integrated into the turret. The 60-mm mortar represents a very interesting and effective addition to tank armament. It can be used to engage soft targets with high explosive bombs or to fire rr 3 smoke or illuminating bombs. A major advantage of the mortar is that it makes more of the main armament ammunition available against hard targets. As it happens, the Merkava Mark 2 carries 62 rounds, which is more than most other tanks, and this, together with its 60-mm mortar, means that it can engage a significantly greater number of targets before it needs to be resupplied with ammunition. Fire Control and Automotive Characteristics To ensure the effectiveness of ita main armament, the Mark 2 is fitted with an advanced fire control system. This has been developed in Israel, by the Elbit Company, and incorporates a neodymium-YAG laser range finder as well as a number of environmental sensors. The fire control system feeds the appropriate superelevation and lead information into the gunner’s periscopic sight, which has a pivoted head mirrorand 8x magnification. As in Soviet and French tanks, there is no auxiliary gunner’s sight, but the gun can be laid by the commander using his periscopic sight. The latter is of the panoramic type and has zoom optics with a magnification which the command-

”Even when some of the Merkavas were set on fire, none was burnt-out beyond repair ... P 8 er can vary, by means of a foot pedal, from 4x to 2Ox. Panoramic periscopes are sometimes claimed to cause disorientation, but this does not appear to have been a problem for the commanders of the Merkavas. The gun controls are electro-hydraulic and stabilized. To reduce the danger of fires associated with high pressure hydraulic systems, the hydraulic power pack of the Merkava is isolated behind the bulkhead in the turret bustle. In addition, the Merkava is fitted with a highly effective Halon fire and explosion suppression system, developed in Israel by the Spectronix Company. As a temporary measure, Merkava Mark 2 is fitted with the same AVDS-1970-5A diesel as the Mark

1. This Teledyne Continental engine is a 900-hp development of the familiar 750-hp AVDS-1970 diesel used in US. M60 tanks. In the future, the Mark 2 is to be fitted with a further development of this engine with an output of 1,200 hp. With its current engine, the Mark 2 has a power-to-weight ratio of 15 hp per metric ton. This is not high by the standard of the US. M1, but is higher than the power-to-weight ratio of the British Chieftain tank and is about the same as that of the M60A3 and of the Soviet T-62. Moreover, the same power-toweight ratio did not prevent the original Mark 1 tanks from performing very successfully during the 1982 “Peace for Galilee” operations in the Lebanon. Similarly, its weight did not prove a handicap to the Merkava. Because it is so well-armored, the Mark 2 is inevitably heavy. But at 60 metric (or 66 US.) tons it weighs no more than the new British Challenger and it is only a few tons heavier than the M1 or the German Leopard 2. In any case, Merkavas were better able to cope with the hilly terrain of the southern Lebanon than some of the lighter tanks used there, and contrary to the in-sinuations of some commentators, their overall mobility proved more than adequate. The new 1,200-hp engine will obviously make the Mark 2 more agile, but its automotive performance is already better than that of the Mark 1. This is due to its new, Israeli-built, transmission which is as advanced as any tank transmission currently in use and makes the Mark 2 not only easy, but also pleasant to drive. Battlefield Experience In addition to all its commendable design features, the Merkava Mark 2 must also be credited with the successful experience under fire acquired with its predecessor, the Mark 1 Merkava. This experience was gained during the 1982 operation in the Lebanon, where the Merkavas were exposed to enemy weapons ranging from the RPG-7 to the 125-mm guns of Soviet-built tanks and HOT antitank guided missiles - the French-produced equivalent of the TOW. Since no tank can ever be made invulnerable, the armor of some Merkavas was inevitably perforated. But the percentage of them which suffered this fate was con-. siderably smaller than that of other tanks, showing the effectiveness of the Merkava’s protection. What is even more significant, the number of casualties per tank was only one half of that suffered in the other tanks which had been hit. This clearly proved the concept of using as much of the tank as possible to protect the crew. The precautions taken against fire also paid big dividends, which was shown most dramatically by the fact that no Merkava crewman was burnt to death - something that has probably not happened before with any other type of tank engaged in major armored operations. Even when some of the Merkavas were set on fire, none was burnt-out beyond repair, and the writer saw for himself battle-damaged tanks being rebuilt at the IDF Tank Depot where the Merkavas are produced. Other Merkavas, which suffered less severe damage, were repaired in the field in less time and with less effort than other types of tanks. This applied, among others, to damage by mines, due largely to the adoption of the externally mounted and easily replaceable suspension components. All reports indicate that the Merkavas were very successful at killing enemy tanks, which included not only the Soviet-built T-62, but also the T-72. Thus, the Merkavas fully proved themselves in the field and became the first and, so far, the only tanks of the generation developed since the 1960s to be battle-proven.

RICHARD M. OGORKIE-

WlCZ is a consulting engineer and lecturer at the Imperial Collegeof Science and Technology in London. An advisor on armor to many nations, he participated in the U.S. Army’s Armored Combat Vehicle Technology Program and has performed studies for the Defense Advanced Research Projects Agency. Over the years, he has written 75 articles that have appeared in Armor. november-december 1985 43