Defence engine

ENORMOUS machines are lined up on a maidan. One of them, painted in olive green, looks like a huge stack of massive boxes piled up on wheels. But as the engine revs up, the boxes open and buoys balloon out. In no time, the Amphibious Floating Bridge and Ferry System (AFFS) is ready to carry battle tanks and trucks across rivers.

Some distance away stands an enormous Tatra truck with platforms behind the drivers cabin. At the touch of a button, five such platforms, each 15 metres long, open out and form a 75-m-long bridge on telescopic legs in 90 minutes. This bridge, Sarvatra, can withstand 10,000 passes of battle tanks.

Nearby is what looks like a modified battle tank, with massive hammers at the end of flails. As the machine erupts to life, the hammers smash mines buried up to a depth of 25 cm in the ground, tossing them out and clearing a 4-metre-wide safe lane for vehicles to pass. This is the Counter Mine Flail T-72.

We are a multifaceted organisation, said B. Rajagopalan, Director, Research and Development Establishment (Engineers), of the Defence Research and Development Organisation (DRDO), in Pune. Our forte is innovative engineering. All our products are 100 per cent indigenous.

Pune, along with Ambernath and Ahmednagar, all in Maharashtra, is one of the hubs of the DRDO, which provides a broad array of technologies to the Indian armed forces. With 52 laboratories across the country, the DRDO is one of the biggest defence R&D organisations in the world.

W. Selvamurthy, Chief Controller (Life Sciences and Human Resources), DRDO, summed it up: No country has an organisation like DRDO, which delivers a broad spectrum of technologies and systems such as battle tanks, families of missiles, radars, torpedoes and sonars, electronic warfare systems, arms and ammunition including the INSAS [Indian Small Arms System], the Pinaka multi-barrel rocket launcher, shelters for protection against nuclear, chemical and biological warfare, bio-digesters, cream to fight frostbite, and so on.

Pune has four DRDO centres: the R&DE(E), the Armaments Research and Development Establishment, the High Energy Materials Research Laboratory and the Defence Institute of Advanced Technology, which offers M.Tech and Ph.D programmes. R&DE(E)s engineers built the Dakshin Gangotri and Maitri, Indias research stations at Antarctica. Work on the third research station at Antarctica is set to begin.

The work done by the R&DE(E) in re-engineering the Tatra truck into the Sarvatra is awesome. With the help of telescopic legs, the height of the bridge can be adjusted from 2.5 m to 6 m so that it is not easily visible to the enemy. The spans are made of a light but strong alloy of aluminium, magnesium and zinc.

Indias main battle tank, Arjun, has taken the avatar of a bridge laying tank (BLT). The R&DE(E) did this by replacing the tanks gun and turret with the bridge launcher. The bridge is cantilevered over chasms or across rivers to cover a distance of 26 m with a width of 4 m. The BLT-Arjun carries two halves of a bridge. At a wet or dry gap, the launcher slides the two parts and docks them to each other in such a way that the far end of the second half touches the other bank. The BLT then crosses the bridge, turns around, retrieves the bridge after undocking its two halves, folds it and is ready to move with the armoured column. U.R. Gautam, Joint Director R&DE(E), called it a great piece of engineering.

The laboratory has also modified the T-72 battle tank into a BLT, which can launch a bridge 20-m long and 4-m wide in just five minutes. The tank loses its gun and turret, but the drivers compartments remain to provide a clear view to manoeuvre it. The system has an anti-aircraft gun to guard against aerial attacks and a smoke discharger to lay the bridge under a smoke-screen. It has beta-light markers to guide the traffic at night. The Heavy Vehicles Factory at Avadi in Chennai produces the BLT T-72s. The Army has bought 12 of them and is likely to place orders for more.

The Combat Engineering Group led by N.B. Vijayakumar came up with the Counter Mine Flail by fitting flails and hammers to the T-72 tank. No other country except Germany has done this on a tank, said Gautam.

The Counter Mine Flail has a series of 10-kg hammers that pulverise mines by beating them at 400 revolutions a minute, said Naresh Kumar, a scientist. The Counter Mine Flail T-72 has a separate power source and does not tap the T-72 main engine power, he added.

Another innovation is a machine that lays mats made of aluminium alloy to help vehicles in marshy terrain. The AFFS metamorphoses from a 10-m-long box-on-wheels into bridge-cum-ferry, which is 28.4-m long and 3.6-m wide in just nine minutes. The whole body is watertight. It can also be used as a ramp, said Gautam.

The R&DE(E) personnel have also built a series of launchers (platforms with power and air supply) for firing missiles such as Agni, Akash, Prithvi and Trishul. Rajagopalan is particularly proud of the launcher plus control system built for the K-15 missile that will be fired from INS Arihant, the nuclear-powered submarine.

In a brilliant piece of engineering, the teams headed by V.V. Parlikar and P.M. Kurulkar, both Joint Directors, modified the T-72 battle tanks chassis into a launcher system for firing surface-to-air Akash missiles. The Combat Vehicles Research and Development Establishment (CVRDE) at Avadi helped them modify the T-72 for this role. The launchers electrical systems are servo-driven. The swivelling launcher has a 360-degree firing freedom. The launcher has proved its worth with 60 flights of Akash taking off from it. The IAF has placed orders for 16 launcher systems on trailers, Parlikar and Kurulkar said.

Daksh speaks for the ingenuity of the R&DE(E). It is a battery-operated robot on wheels and its primary role is to recover improvised explosive devices (IEDs). It locates IEDs with an X-ray machine, picks them up with a gripper-arm and defuses them with a jet of water. It has a shotgun, which can break open locked doors, and it can scan cars for explosives. Daksh can also climb staircases, negotiate steep slopes, navigate narrow corridors and tow vehicles. Alok Mukherjee, a scientist, said: With a master control station (MCS), it can be remotely controlled over a range of 500 m in line of sight or within buildings. Ninety per cent of the robots components are indigenous. The Army has placed orders for 20 Dakshs.

Research is under way at the Composites Research Centre (CRC) of the laboratory on light-weight structures. According to Kiran Akella, a scientist, the centre has developed a bridge made of carbon-epoxy composites. This is 30 per cent lighter than the ones made of aluminium. The 5-m-long bridge weighs just 1.2 tonnes, but it can carry a 70-tonne battle tank. Fibre-optic sensors embedded in the bridge help it monitor itself.

According to Rajagopalan, the R&DE(E), with support from the Navy, has ventured into building the superstructure of Corvette-class warships with carbon-epoxy composites. Next would be the development of ship hulls with fibre-reinforced plastic. The centre is developing hulls made of composites and ceramic armour for infantry combat vehicles.

An offshoot of composites research is the development of hip implants. Makarand Joshi, who conceived it, explains that imported hip transplants, made of steel, are expensive and are suited only for the European body structure.

We have customised the implant for individuals, Joshi said. It has been tested on 40 cadavers. Clinical trials will start soon after the Ethics Committee of the Medical Council of India clears it.