ARJUN tank is the a 3rd gen indigenous INDIAN tank produced by DRDO for INDIAN ARMY.It features a 120 mm rifled main gun and one 7.62 mm and a 12.7 mm machine gun for CQB. It is powered by a  by a single MTU multi-fuel diesel enginewhich produces 1400 hp. It has a 4 man crew (driver ,commander,gunner and loader) and Chemical, biological, radiological and nuclear defense (CBRN defense) and automatic fire extinguishing system.
It has multilayered defence and  its preotective armour is developed by DRDO which is called "KANCHAN" armour  which in sanskrit means "gold" and it is a composite armour which is superior to most 3rd gen tank armours .

The development of tank started in 1972 by DRDO but till 1996 it did not get much support from govt and in 1996. The project suffered a lot of REQUIREMENT CHANGES because during the development period throughout the globe alot of new ANTI-TANK weapons and tactics were developed and so army kept changine requirements which increased not only the development cost but also time and the weight of the tank(originally planned to be near 46 tons but then increased to 59 tons for mk1 and 68 tons for mk2 version).

The delay in production of tank forced army to procure T-90 BHISHMA in large numbers from RUSSIA which is now the real MBT of INDIAN ARMY .Earlier  T-90 were bought in small batches but later the govt did a deal and India became a licensed producer of T-90 BHISHMA and now army has about 1200+ T-90's and nearly 1000 more are to be produced by 2020.

Even though the T-90 are considered to be the MAIN BATTLE TANK OF INDIAN ARMY but this did not mean that ARJUN tank was no more useful and that army did not need an INDIAN tank. 
So ARJUN entered service with the Indian Army in 2004. The Indian Army ordered 124 Arjuns MK1 & The Army placed an order for an additional 124 Arjun Mk-I tanks on 17 May 2010 making it  248 ARJUN MK 1 tanks but later changed the order saying it would like rest in MKII configuration.

The mk1 version of ARJUN was good but faced issues when operating at high temp regions where it faced issues like low speed , gailing of electronic systems and overheating though most of them were later rectified but still this led to development of more advanced ARJUN MK2 .


Arjun Mark II has a total of 93 upgrades, including 13 major improvements. The major upgrades are missile-firing capability against long-range targets, panoramic sight with night vision to engage targets effectively at night, containerisation of the ammunition, enhanced main weapon penetration; additional ammunition types, explosive reactive armour, an advanced air-defence gun to engage helicopters; a mine plough, an advanced land navigation system and a warning system which can fire smoke grenades to confuse laser guidance,night vision for driver ,an advanced hydropneumatic suspension system which provides very good comfort to the crew etc.

Also a secondary power source was added which enables the systems of tank to function when the engine of tank is off .

A comparative trial was conducted by the Indian Army in March 2010, in which the Arjun was pitted against the T-90. The trial pitted one squadron of Arjuns against an equal number of T-90s. Each squadron was given three tactical tasks; each involved driving across 50 kilometres of desert terrain and then shooting at a set of targets. Each tank had to fire at least ten rounds, stationary and on the move, with each hit being carefully logged. In total, each tank drove 150 km and fired between 30-50 rounds. The trials also checked the tanks' ability to drive through water channels 1.5-1.8 metres deep. 

Protection was improved by using improved Kanchan armour, along with the locally developed explosive reactive armour modules in the turret.

The tank underwent developmental trials in 2012, at Rajasthan's Pokhran field firing range which continued for two months with the focus on 19 parameters. DRDO is to start production of 124 Arjun Mark II tanks for the Indian Army after the success of these trials. The Mark-II version completed most user trials in 2012 and 2013 and displayed impressive performance. The new features of the Arjun Mark 2 received favorable responses.

Weight 58.5 tonnes (57.6 long tons; 64.5 short tons)
Mk.2=68 tonnes (67 long tons; 75 short tons)
Length 10.638 metres (34 ft 10.8 in)
Width 3.864 metres (12 ft 8.1 in)
Height 2.32 metres (7 ft 7 in)
Crew 4 (commander, gunner, loader and driver)

KANCHAN ARMOUR -ARJUN is protected by KANCHAN armour which is a composiet and comparitively lighter (less dense than conservative armours).It gives excellent protection and can withstand APFDS and HEAT rounds. In trials conducted in 2000 KANCHAN armour protected ARJUN tank from a T-72 even when hit at point blank range. It also demonstrated the capability to defeat HESH and APFSDS rounds, which included the Israeli APFSDS rounds.

A Mobile Camouflage System has been developed and integrated into the Arjun. 

A new 1500 hp engine is being developed that will eventually replace the present engine. An allocation of 400 million (US$5.9 million) has been allocated for the project which is expected to be completed within five years.

The project has not only provided our nation with a capable tank but this has also helped in creating the modern tech indigenously .
Now India has experience and knowledge which it needs for developing better tanks and now DRDO and ARMY are exploring the possibility of having a future main battle tank.
It is not hard to understand that ARJUN still has lot to develop. It surely is a capable tank but it will mature more with time and develop into better system.