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It was a brutal test of helicopter and pilot. As the Dhruv Advanced Light Helicopter (ALH) shuddered towards the icy helipad on a 21,000-foot ledge overlooking the Siachen Glacier, the pilots could see wreckage from earlier helicopter crashes dotting the base of the vertical ice walls on either side. Ahead lay the Indian armys infamous Sonam Post, the highest inhabited spot on earth, and an extreme example of why the military so urgently wants the Dhruv, which has been customised by Hindustan Aeronautics Limited (HAL) for high altitude operations.
Very quickly, the Dhruv demonstrated its superiority over the militarys tiny, single-engine Cheetah helicopters, which can barely lift 20 kilos of payload to Sonam. Touching down on a tiny H-shape formed on the snow with perforated iron sheets, the Dhruvs pilots signalled to one of the soldiers on Sonam to climb aboard. Effortlessly, the Dhruv took off, circled the post and landed again. Another soldier clambered onto the helicopter and the process was repeated, then with a third, and then a fourth soldier. Even with all Sonams defenders on board, the twin-engine Dhruv --- painted incongruously in the peacock regalia of the IAFs aerobatics team, Sarang --- lifted off and landed back safely.
This helicopter is simply unmatched at high altitudes, says Group Captain Unni Nair, HALs chief helicopter test pilot, who flew the Dhruv that August morning during hot-and-high trials at Sonam. That term means flying at extreme altitudes in summer, when the heat-swollen oxygen is even thinner than usual. The army wanted the Dhruv to lift 200 kilos to Sonam; we managed to carry 600 kilos.
Powering that world-beating performance is a new helicopter engine, called the Shakti, which HAL commissioned French engine-maker, Turbomeca, to design for operations along Indias high-altitude borders. It is this engine that makes the new Dhruv Mark III --- the first five of which were delivered to the army this month --- far superior to the Mark I and Mark II Dhruvs, which were built with a less versatile engine. The Shakti, which will start being built under licence at HAL soon, will now power an entire family of HAL-built helicopters: an armed version of the Dhruv; the Light Combat Helicopter (LCH); and the single-engine Light Utility Helicopter that is still on the drawing board.
The Shakti-powered Dhruv Mark III is changing the operational dynamics on Indias high-altitude Himalayan defences. The capability to airlift soldiers will allow far-flung posts to be manned with fewer soldiers. In a crisis, jawans can be airlifted quickly from lower altitudes to threatened areas, and casualties can be evacuated. And when they see a Dhruv flying in, the soldiers on isolated piquets like Sonam know that there is space on board for essential stores, and even occasional goodies from families and comrades.
HAL Bangalore has already begun handing over Dhruv Mark IIIs to the Leh-based 205 Aviation Squadron for operations in Siachen. With the military demanding 159 Dhruvs in quick time, HAL can hardly build these helicopters fast enough. This years production rate of 25 Dhruvs will be accelerated from 2012 to 36 helicopters annually. The current order includes 54 weaponised Dhruvs --- termed Advanced Light Helicopter --- Weapons Systems Integrated, or ALH-WSI --- armed with anti-aircraft and anti-tank missiles, rockets and a 20-millimetre turret gun. The ALH-WSI is scheduled to begin weapons trials in Orissa in April.
The success of the ALH programme, heralded by the Dhruv Mark III, comes after years of struggle and criticism. Last August, the Comptroller and Auditor General (CAG) noted, 90% of the value of material used in each ALH is still imported from foreign suppliers.
But HAL chief, Ashok Nayak, and his helicopter chief, Soundara Rajan, point out that indigenisation does not mean building every component of an aircraft. Citing the example of the Dhruvs HAL-built mission computer, Soundara Rajan asks whether the imported microchips inside make the mission computer any less indigenous. He sums up HALs helicopter strategy as follows: We will design our helicopters; develop the critical technologies of helicopter transmissions; manufacture composites; and integrate and assemble the helicopter. We will outsource the manufacture of sub-assemblies and components and structures to any vendor on the globe that offers us cost-effective solutions.
Despite meeting important performance objectives, the ALH has one major hurdle to cross. Its Integrated Dynamic System (IDS), which carries power from the Shakti engine to the helicopters rotors, was found to suffer from excessive wear and tear, requiring replacement at frequent intervals. Although HAL claims to have fixed that by making 6 modifications, reputed Italian aerospace designer, Avio, has been hired to audit the Dhruvs IDS, a painstaking process that could take a couple of years. With the same IDS slated for the LCH and the ALH-WSI, HAL is taking no chances.
This careful approach underpins HALs ambitious foray into the helicopter business, which Nayak says will generate 25% of HALs revenue in 12-15 years.
In the last 40 years, we have built 700 helicopters, says Soundara Rajan. The next 700 will be built in 20 years. The ones built so far were second generation machines; now we are working in fourth generation technology.
Broadsword: In Siachen, Dhruv proves a world-beater
