Arjun Main Battle Tank review, road test

We didn't fire a shell but actually got behind the controls of the main weapon system, the 120mm gun, and the laser and infrared-aided Fire Control System, recently improved along with the hardware suppliers. 

Sat on the gunner's stool, at the feet of the commander, the gunner can either use his day-sight or an infrared one at night. Before you engage a target, you have to place the turret into stabilised mode, in which it literally floats up like a hovercraft with a suspension of its own. This seems to work really well, and the tip of the gun remains absolutely still, however bumpy the terrain. The gunner uses an aircraft-like yoke, which elevates the gun and swings it around. Once a type of shell and target is selected, the gunner activates the laser and presses the fire button - as simple as that. The real hard work is done by the ballistic computers. They gather information on the distance to the target from the laser, take into account the wind velocity, air temperature, air pressure and type of ammunition selected, all in real-time. The computer then adjusts the offset and fires. This takes place in milliseconds. The commander sitting above the gunner has his own 'panoramic sight', which rotates through 360 degrees. He can select another target while the 120mm gun is taking a shot, lock onto it and then 'hand it over' to the gunner with a press of a button — as the turret automatically aligns itself with the new target.

The Arjun's favourite weapon is the lethal fin-stabilised armour-piercing sabot, basically a very high energy dart that explodes out of the barrel at almost five times the speed of sound; it carries more energy than a 10-ton truck travelling at 120kph. Upon impact, this very high density tungsten projectile concentrates all its energy into the area of a one-rupee coin, and bores deep into its target with all that energy behind it. FSAPDS rounds like these have been known to penetrate more than 10 inches of steel and even bore diagonally through gun barrels at over a 2.5km range. The other type of shell, the High Explosive Squash Head, carries explosives of varying hardness for both soft and hard targets. An Anti-Tank missile has also been successfully fired from the barrel of the Arjun, with no changes needed. It is lethal beyond a range of four kilometres at night and six during the day, and can be aimed by another tank or soldier somewhere else on the battlefield.