The Merkava (Hebrew: "chariot") is a main battle tank used by the Israel Defense Forces. The tank began development in 1970, and entered official service in 1979. Four main variants of the tank have been deployed. It was first used extensively in the 1982 Lebanon War. The name "Merkava" was derived from the IDF's initial development program name.
The Merkava Mark III was introduced in December 1989 and was in production until 2003. As of 2016, the Merkava III is by far the most numerous tank in frontline IDF service. Compared to the Merkava II, it has upgrades to the drivetrain, powertrain, armament, and electronic systems. The most prominent addition was the incorporation of the locally developed IMI 120 mm gun. This gun and a larger 1,200 horsepower (890 kW) diesel engine increased the total weight of the tank to 65 tonnes, but the larger engine increased the maximum cruising speed to 60 km/h (37 mph). The turret was re-engineered for movement independent of the tank chassis, allowing it to track a target regardless of the tank's movement. Many other changes were made, including:
- External two-way telephone for secure communications between the tank crew and dismounted infantry,
- Upgraded ammunition storage containers to minimize ammunition cook-off,
- Addition of laser designators,
- Incorporation of the Kasag modular armor system, designed for rapid replacement and repair in the battlefield and for quick upgrading as new designs and sophisticated materials become available.