The Nag Anti-Tank Guided Weapon (ATGW) has been under development by Bharat Dynamics and the Defence Research and Development Laboratory (DRDL), which is part of the Indian Defence Research and Development Organisation (DRDO), to meet the operational requirements of the Indian Army for a vehicle and air-launched anti-tank weapon with a maximum range of at least 4,000 m.

Development of the fire-and-forget Nag missile started in the 1980s but, as with many Indian missile research and development programmes, there have been numerous delays due to technical difficulties.

First Nag test launches commenced in 1990 and it was expected that series production would have commenced in the mid-1990s. This, however, was delayed and user trials only commenced early in 1999. It is expected to enter volume production for the India Army in the near future.

Bharat Dynamics currently manufactures under licence the Euromissile Dynamics MILAN and Russian Konkurs anti-tank guided weapons and their associated launchers. Brief details of these are given in the following two entries.

In addition to the tripod-mounted ground-based version of the Nag ATGW, there are at least three other versions - the self-propelled Namica and two helicopter-based versions. The latter will include the Advanced Light Helicoptem (ALH) which will have eight missiles in the ready to launch position.

The Namica is based on the Sarath, the Indian built version of the Russian BMP-2 tracked infantry combat vehicle and will have a total of four Nag ATGW in the ready to launch position with additional missiles being stowed inside. These can be reloaded from within the vehicle under full armour protection.

The Namica retains the full amphibious capability of the Sarath and is fitted with an auxiliary propulsion unit (APU) as standard. This enables the onboard equipment, including the missile system, to be used with the main diesel engine switched off. BITE is fitted as standard.

Nag is claimed to be a third-generation top attack ATGW and is expected to enter production in 2000-01.

It weighs 42 kg at launch, has a range of more than 4,000 m (some sources have stated 6,000 m) and is of the fire-and-forget type. A tandem High Explosive Anti-Tank (HEAT) warhead is fitted to counter Main Battle Tanks (MBTs) fitted with explosive reactive armour.

The Nag is ejected from its launch tube by the combined thrust of the booster and sustainer propulsion systems after which the fins unfold.

The airframe sections are made of high strength, low-weight composite materials as are the folded wings and fins with the booster and sustainer rocket motors being made by high strength aluminium alloy. The missile uses a high energy Nitramine based smokeless propellant.

Control of the missile in roll, pitch and yaw is achieved by moving the rear fins with all electric actuating system using power from the thermal batteries.

Three different seekers have been developed for Nag, Charge Coupled Device (CCD) based day version, Mercury Cadmium Telluride (MCT) Focal Plane Array sensor based Imaging Infra-Red and Millimetric Wave (MMW) active radar seeker for all weather target engagement. It uses the Lock On Before Launch (LOBL) concept. The version with the CCD seeker is expected to be the first version of Nag to enter production.

According to the DRDO, the Nag has been designed with stretch potential for extending the range for Lock On After Launch (LOAL) capability in the future.

Development. Not yet in production or service.