The Mk 4 — ’s Newest MBT Enters Service

by Lieutenant Colonel David Eshel, IDF, Retired

During a ceremony in June 2002, the The new main armament can fire all puterized ballistic calculations and com- Israel Defence Force (IDF) unveiled its types of 120mm , includ- pensations for climatic changes, and in- new member of the Merkava family, ing APFDS-FS kinetic rounds, high- ternal pressure shock resulting in barrel the Mk 4 Main (MBT). explosive antitank (HEAT) munitions, distortion also effectively controlled by antipersonnel/antimaterial ammunition the video thermal sleeve. Special sen- The new tank, a fourth generation de- velopment of the 1979 Mk 1, which (APAM), as well as the latest Israel Air- sors monitor the precise gradient changes craft Industries-developed, gun-barrel close to the firing sequence in the bar- saw its first combat action during the launched, -homing antitank (LA- rel line-of-sight, which can distort the 1982 Lebanon Campaign, includes new design concepts, which rate it among HAT) . The loader can feed the ballistic angle. breech from a fully automated, fire- the best in the world for survivability proof revolving magazine, accommo- Loading the breech during cross-coun- and . try movement can affect crew safety. dating up to 10 ready rounds, and de- As in most , the gun is stabilized According to the “father of the Mer- livering four types of automatic ammu- kava,” retired Major General , nition for selection. The semiautomatic in and traverses during move- ment, but the barrel changes its eleva- who, for over 30 years, has been the loading system is electrically operated tion angle in relation to the inclined tur- driving power of this revolutionary and ready-round selection is controlled tank design concept, “The Merkava Mk ret level. To prevent this, a new system by a microprocessor. was introduced, which locks the barrel 4 being a fourth generation combat- The new Merkava Mk 4 design elimi- during the loading process in a speci- proven vehicle, represents a quantum leap forward in modern tank design in nates the loader’s hatch, improving the fied elevation angle for easy loading se- loader’s position to serve the gun breech quence, then regains its former stabi- all its parameters, protection, firepow- while in a sitting position. A TV moni- lized position after the loading process er, mobility, and combat control.” tor screen, instead of the traditional op- is completed. Improved Firepower tics, improves external observation. The loader also operates the 60mm Other improvements to the Mk 4 in- The Merkava Mk 4 mounts a new, lo- clude a dual axis gunner’s sight and dual cally produced, 120mm gun, tubes from inside the tank. This weap- axis stabilized ’s panoramic designed to sustain higher internal bal- ons system fires HE and illumination sight, both equipped with an advanced listic pressures and generate superior rounds. forward-looking and TV screen , which is specified for The tank is equipped with a modern for day and night observation channels advanced kinetic energy munitions. fire control system, which includes com- that contributes substantially to en- ARMOR — January-February 2003 45

hanced first-hit probability, surpassing Protection and Survivability ing individual air conditioning (micro- the former Merkava Mk 3 (Baz) version, cooling) designed for sustained combat which already achieved remarkable gun- The principles on which the Merkava under adverse climatic conditions. nery standards. family was designed are maintained in the Mk 4, namely, enhancing crew pro- Battle Management and A second-generation automatic track- tection and maximum survivability in Control Systems ing system (ATS), which locks on tar- high-intensity, fire-saturated combat. get at several kilometers range, auto- The emphasis on “combat” is necessary The Merkava Mk 4 uses a new inte- matically tracks moving ground targets to clarify the recent terrorist incidents grated battle management system (BMS) and low-flying helicopter targets. The in the Gaza Strip, where two Merkava designed by , which pro- gunner’s sight is locked onto its desig- Mk 3 tanks were blown up, in separate vides rapid communications network- nated target throughout the firing se- attacks, by massive explosive charges, ing between the tactical tank command- quence, irrespectively of any evasive surpassing 100 kg each. er and his subordinate units. It enables action the target attempts when aware the commander to plan missions, navi- that it is coming under attack. The ATS Against an explosive force of such gate, and continuously update situation- is based on video output from either a magnitude ripping into its underbelly, al awareness. The system also records TV camera (daylight channel) or ther- none of the Merkava models, nor any data for operational debriefing by using mal imaging camera (night channel). other tank in the world, are designed to the tank’s Vectop digital data recorder. remain intact without compromising This records and restores sight images Firing-on-the-move is conducted with mobility, through abnormal weight ad- and observation data collected during an ultra-fast gun stabilizing electric tur- ditions, to its protective armor suit. ret drive system, which enables locking missions. This data can be shared with Designed for modern combat opera- other elements, using the same network the sight while moving over rough with the BMS, to report enemy targets. cross-country terrain. An instantaneous tions, top priority in the Mk 4 was giv- smoke self-screening system is mount- en to enhanced protection against third Such a concept is rapidly becoming an essential part of the new digitized land ed either side of the turret. or fourth generation antitank guided , with special emphasis on top- forces integrated concept, New Tank Ammunition Used in attack, terminal-guided . The combining armor, antitank, and combat Merkava Mk 4 Gunnery revolutionary concept of placing the helicopters in combined op- The LAHAT round, designed by Is- power pack in was maintained. erations. rael Aircraft Industries, was developed Each member in the Merkava Mk 4 to the IDF armor ’ specification. To achieve maximum protection of crew has an individual flat-panel color Using the semi-active laser homing guid- the upper turret, the loader’s hatch was display at his station, showing the ance method, LAHAT can be desig- eliminated in the Mk 4 design. This en- status of systems related to his specific nated by the firing tank crew or through ables a full extent of the modular ar- task. The tank gunner and commander external designation from ground, mo- mor protective suit on the turret top can also monitor the respective sight bile, or airborne observers. without compromising the additional images on their individual display hatch, which had so far remained a screen. The tank commander can use Firing the round requires minimal ex- conceptual hindrance based on the lack posure in the firing position, and can be his map display to navigate, orientate, of alternative observation systems. This and control his subunits. directed through the commander’s sight problem has now been solved. by only maintaining LOS during mis- For full perimeter defense, the Mer- Optronics Equipment for sile , when “turret-down.” The mis- All-Around Observation sile’s trajectory can be preselected for kava Mk 4 is fitted with a latest state- either top attack (tank) or direct attack of-the-art Amcoram LWS-2 laser warn- The design concept of the Merkava (helicopter) engagement. The missile ing system, its sensors capable of de- Mk 4 version was also based on combat uses a tandem warhead, which can de- tecting incoming missiles soon after experience, including high-risk close feat modern armor and reactive panels. launch. The threat warning display is combat in urban environment, which, installed at the tank commander’s sta- Another round to be introduced in Mer- in contrast to warfare in open tion. Although details are classified, the terrain, is extremely hazardous to tank kava is the APAM munition. Already in Mk 4 is believed to be protected by a crews observing targets from open use with the former Merkava tanks that new type of hybrid armor, which can be mount the 105mm main gun, a 120mm hatches, which was traditional in the conformed from modular elements to IDF’s armor corps doctrine. Thus, top smoothbore version is soon to be in- match specific threats. Another classi- priority was placed in the design of a cluded in the Merkava Mk 4 model. fied item is an advanced active full pe- The APAM constitutes an ultimate so- new concept, which affords continuous rimeter defense system incorporated combat with closed hatches to all crew- lution to the growing threat to tanks, with the LWS. members, without impairing their full especially in , where tank-killer lurk with modern le- Enhanced survivability against fire perimeter observation, at close and long thal antitank weapons. The new round hazards is gained through the all-elec- ranges. uses the proven concept of antiper- tric turret-control system, which elimi- The Vectop Tank Sight System (TSS) sonnel munitions based on controlled nates all remaining hydraulic fluid. An integrates an array of video cameras in- . It deploys submunition advanced version of the automatic fire stalled in different positions around the shrapnel at defined intervals, covering suppression system is installed. The tank to enable the crew to cover “dead a wide lethal area against soft targets. crew is also protected against nuclear, zones” in the tank’s surroundings. An Each fragment is shaped to have enough chemical, and biological warfare by a array of four cameras provides com- kinetic energy to penetrate convention- central high positive pressure system in plete peripheral coverage (360 degrees), al body armor, or other materials. the fighting compartment, also provid- and the top of the tank, including re- 46 ARMOR — January-February 2003

verse movement, which the driver can rect-injection , and paired with system, which never surpasses g-1. In monitor without impaired vision. the Renk RK325 automatic transmis- comparison tests with other vehicles un- For protection against enemy fire, all sion, comprises the Merkava Mk 4 dergoing the same criteria, when speed power pack. It offers the best power-to- approached g-9, crewmembers suffered the outboard cameras are imbedded in weight ratio at such weight levels (65 injuries and system malfunctions. In the armored cases outside the tank. They provide high-resolution pictures to mon- tons). A computer connected to the Merkava Mk 3, at twice that speed, on itors installed in the driver’s position driver’s panel and to the the same test bed conditions, the g-force system controls the engine. Field tests never exceeded g-1! and fighting compartment crew posi- covered over 10,000 km in rough ter- tions. rain successfully. Although details are still classified, The optronics provide full and clear the Merkava Mk 4 suspension system An auxiliary engine provides power also underwent additional improvement, vision for the tank commander to oper- when the tank is on “silent watch” for ate under closed hatches, using an ad- which, combined with the new power- vanced panoramic sight for all-round battery recharging and night observa- to-weight ratio, could even surpass the observation. The turret tion, with full systems operating while data of the Mk 3. the main engine is shut down. can also be operated from under armor by being mounted on a circular revolv- One of the unique advantages of the ing ring for automatic traverse. The entire Merkava family is its remarkable commander’s sight has override to the cross-country capability through its spe- Retired Lieutenant Colonel David gunner’s sight while data is being con- cially designed suspension system. This Eshel, Israel Defence Force, is a tinuously relayed in both directions. All is typified by a powerful spring and ro- freelance journalist and serves as a sights are day/night stabilized, render- tary coil-spring design, differing from defense analyst for several ing the commander’s hunter/killer ca- the double spring system used in previ- journals. Following his brief service pability. ous Merkava Mk 1 and Mk 2 models. with the British Forces during World Propulsion and Mobility The Merkava Mk 3 Baz suspension is War II, he became one of the found- optimized for fast ride over extremely The Merkava Mk 4 is powered by a difficult terrain, like the basalt rock ing members if the Israeli Armoured new 1500 hp , which im- strewn Golan Heights. Corps and served as a career offi- proves its mobility substantially, com- cer with the IDF for 26 years. Edu- pared to the former models, which were With vertical road travel of up cated at the French School to 600mm in diameter, the crew is at Saumur, he later held various powered by 900 and 1200 hp respec- given a softer ride, which reduces fa- tively (Mk 1/2 and Mk 3). tigue. The suspension meets the strin- command and staff assignments The GD833, co-pro- gent requirements of 60 km-per-hour in and fought in all of the Arab-Israeli duced in the United States by GDLS and rough country and reduces the impact wars, including the 1973 conflict, MTU (which also powers the French on its crew thanks to the excellent ab- when he served as the Armoured GIAT Leclerc), is a liquid-cooled, di- sorption capability of the suspension Corps’ chief of signals.