Traditionally in our country when we discuss about “Indigenous” aircraft, we don’t really consider them very advanced or see them highly. Without really knowing about the product we are usually very quick to pass the judgement & label it of poor quality or not matching with western standards.
Well, the Advanced Light Helicopter Dhruv made by HAL completely changed this notion. It was introduced in 2002 with the Indian Armed Forces & the helicopter gained popularity in no time due to its excellent flight characteristics, practically laid cabin, low vibrations & frugal running cost. Naturally, soon it was adopted as the de-facto utility helicopter of the Indian Armed Forces. In fact, it is one of the very few aircrafts to be ever put into service by all three branches, the Indian Air Force, Indian Army & the Indian Navy. The cherry on the cake is the aircraft is designed & developed by HAL. However, MBB from Germany did played the role of design consultant & collaborative partner.
Its development started in 1984. The developmental journey was troubled & the helicopter faced many roadblocks during its development. Initially scheduled, the first prototype was supposed to fly in 1989 but flew in 1992. Soon after this Indian army requested a design change to suit their requirements which delayed the program even further. Due to Pokhran tests in 1998, an embargo was imposed on India & the ALH program lost the support of the American firms which supplied the engines. A French engine was selected as a replacement from Turbomeca which is still in the current use. Finally overcoming all the political & design hurdles, the aircraft was inducted in the Indian Armed forces in March 2002.
Interestingly ICG (Indian Cost Guard) was the first organisation to operate the Dhruv in 2002. Soon after this Indian Army placed a huge order of 166 helicopters to replace their aging fleet of Cheetah & Chetak helicopters. This provided HAL with the confidence to boost the production capacity. Since 2008, a maximum of 40 units are being produced every year at the HAL Helicopter Complex depending on the orders. The same year Indian Navy announced that it’ll start using the Dhruv in utility role. This was going to be a wheeled version of the Dhruv instead of the standard skid version. Dhruv also saw orders from Indian Air Force, BSF (Border Security Force), NDMA (National Disaster Management Authority), Home Ministry, ONGC (Oil and Natural Gas Corporation). By the mid-2010s, Dhruv was the face of helicopter fleet of many organisations of India.
HAL has significant experience in developing structures from composites & this capability was exploited while designing the ALH. 29% of empty weight of the aircraft, constituting 60% of the airframe’s surface area is made up of composite materials. For the ALH, an exclusively unique carbon fibre composite was developed by HAL which helped reducing the weight while maintaining the same structural tensile & bending strength. The tail boom is high which makes way for a pair or side hinged rear doors. This unique feature of the ALH Dhruv as these types of rear doors are usually used in larger helicopters. The benefit of having such doors is that while flying in the role of MEDEVAC (Medical evacuation), stretchers with patients can be loaded & unloaded very quickly & effectively. The Dhruv can hold 4 stretchers with a medical attendant.
The airframe is carefully designed to keep the occupants safe in the event of a crash. DGCA has praised its crashworthy design as a few accidents have not caused any fatalities.
The internal fuel capacity is about 1,400 litres which gives it a range of 630 km or about 3.5 hours of endurance. It also has a cargo hook with a rated capacity of 1,500 kg & can lift a vehicle of the size of a stripped-down Gypsy which acts as a fast attack vehicle in any kind of terrain.
Engines of the ALH Dhruv have their own story altogether. The first two iterations of the aircraft the Mk I & Mk II had two 1,000 shaft horsepower engines which enabled the helicopter to carry 12 troops. With passing time, the Cheetah aircraft used for high altitude operations seemed inadequate & the ALH with its 2 x 1,000 hp engines couldn’t fly in the high altitude with substantial payload. That’s when the Mk III version was announced to cater operations such in high altitude regions. For this the aircraft was vastly improved & the major upgrade was the 1,400 shaft horse power Shakti-1H engines. This vastly improved the flight characteristic of the aircraft & enabled it to carry 14 fully equipped troops. On one test, the Dhruv Mk III carried 600 kg load to Sonam Post at an altitude of 6,400 meters against the Army’s requirement of 200 kg.
The Mk III variant is the actual version which brought a lot of positive attention towards the ALH program & hence it became the standard mainstream Dhruv version. It was upgraded with Swedish company SAAB’s IDAS-3 self-protection suite & BOP-L ECM dispenser which allowed it to operate in border areas as well where there is a chance of surface to air missile firing.
ALH Dhruv, especially the Mk III has a commendable reputation in the Armed Forces. It is the go-to utility helicopter for all kind of operations including troop transportation, high officials movement, SAR (Search & Rescue), CASEVAC (Casualty evacuation), MEDEVAC (Medical evacuation), aerial reconnaissance, Commando Heli insertion & extraction & even aerobatic display.
Its usefulness came into limelight during the 2011 Sikkim Earthquake & 2013 Uttarakhand floods during which they were pressed into action in significant numbers. Their compact size, agility, ability to carry up to 16 people to heights of 10,000 feet, and to evacuate stranded people from inaccessible regions like rooftops was highly praised. The ALH Dhruv could carry more people from high-altitude helipads than the heavier Mi-17, and land where the lighter Bell 407 could not. Total flight time during Operation Rahat and Operation Surya Hope was 630 hours, of which 550 hours were dedicated to SAR missions.
Since the helicopter was highly versatile with a massive payload for its size, an armed variant was envisaged in 2012 without making any major modifications to the airframe. This was rather a need as the Mi-35 Hind in service were aging & were due to be replaced in a decade. This led to the development of ALH Dhruv-WSI Mk IV, also named HAL Rudra. The Rudra is a much different helicopter from the previous three variants. It is equipped with forward looking infrared (FLIR), Thermal Imaging Sights Interface, Elbit CoMPASS optoelectronic suite for reconnaissance and target acquisition, RWS-300 radar warning system, LWS-310 laser warning system, MAW-300 missile approach warning system, SAAB IDAS-3 self-protection suite & BOP-L ECM dispenser. On weapons front, it had a French 20 mm turret gun, 70 mm rocket pods, anti-tank guided missiles and air-to-air missiles.
The result, a moderately armed helicopter, able to fly at high altitudes, with decent attack capabilities, which is developed in an incredibly short timeframe. The helicopter can be used in both unarmed and armed roles that include reconnaissance, troop transport, anti-tank warfare and close air support. Again, the aircraft received much love & got order from all three branches of the military including the Navy which was impressed with the capability of the Rudra’s sensors to read the names of ships even from 12 to 14 km.
In September 2020, HAL rolled out 300th unit of HAL Dhruv including all the four variants. This tells volumes of the success of HAL Dhruv, our country’s first indigenous helicopter. Behind this success of Dhruv lies the infinite man hours of coding, testing, validation, iterations & optimisation by the HAL & Indian Armed Forces personnel. This is one aircraft which doesn’t get much attention in the mainstream media that it deserves, but in the community of aviation enthusiasts, the Dhruv is a very highly respected helicopter & has a league of its own.