Customised ALH ‘Dhruv’ Mk-III ready for deliveries to Indian Navy and Coast Guard – Indian Defence Research Wing


SOURCE: Vertical Mag

The first batch of the “made in India” Mark-III variant “Dhruv” Advanced Light Helicopter (ALH) customized for coastal security is slated for delivery to Indian Navy (IN) and Indian Coast Guard (ICG) shortly. This is a landmark event for both sides, being the first bulk order of the Dhruv Mk-III placed on state-owned Hindustan Aeronautics Limited (HAL) by the two services.

While the Indian Army and Air Force have inducted later versions of ALH (Mk-III utility, and weaponized Mk-IV “Rudra”) in large numbers, the IN and ICG have thus far operated only older Mk-I variant with conventional cockpit and Turbomeca (now Safran Helicopter Engines) TM 333 2B2 turboshaft engines.

The customized Mk-III under delivery features a full glass cockpit with HAL’s Integrated Architecture Display System (IADS), more powerful “Shakti” (Safran Ardiden 1H1) engines, and a host of new systems integrated by HAL’s Rotary Wing Research and Design Centre (RWRDC). Two “green” helicopters were handed over to RWRDC by HAL’s Helicopter Division in June 2018 for system integration. The work was completed briskly by HAL in under two years before Covid-19 lockdowns put the brakes on field trials.

After the lockdown restrictions were gradually lifted by Indian government in May 2020, sensor integration and sea trials resumed at Kochi, Chennai and Goa on the first of ICG and IN airframes. As of November, two helicopters churn the air above Bengaluru almost daily for customer training. Acceptance flights by HAL test crew were in progress when this author visited, with the first lot expected to be formally “signaled out” for customer acceptance sorties at the end of November.

The contract for 32 coastal security ALH was inked in March 2017 with ICG as the lead service. The IN order for 16 — to supplement its ageing and depleting fleet of Alouettes (Chetaks) — was dovetailed into this program based on the overarching responsibility for coastal security placed on it by the government of India in the wake of 26/11 (2008) terrorist attacks on Mumbai.

These helicopters (yet to be christened with a unique Indian name) come with latest-generation avionics and role equipment. The helicopters are primarily meant for use in a shore-based role. However, HAL is confident that the rotors will be ready to embark ships should the need arise.

The ICG contract, for instance, directs HAL to test and provide an afloat envelope (SHOLs) for the Mk-III. It also includes a performance-based logistics (PBL) clause — making this the first time a customized variant with tough PBL clause is being offered by HAL to a sea-going customer. (The IN contract does not have PBL built-in, possibly to keep within budget constraints while letting ICG test the waters.)

The selection of systems and customization was done primarily in consultation with ICG. For its coastal security role, the aircraft has a nose-mounted surveillance radar with 270-degree coverage that can detect, classify and track multiple marine targets; it has synthetic-aperture radar, inverse synthetic-aperture radar, and moving target indication classification functions, including weather mode. There is also a multi-spectral electro-optic (EO) pod for reconnaissance, surveillance, target acquisition and range finding with stowable control grip on copilot side.

Other features include a removable medical intensive care unit for the air ambulance role; high-intensity searchlight, loudhailer, 12.7-mm cabin-mounted machine gun (with provisions on the left side), traffic alert and collision avoidance system, V/UHF communication system with data modem, IFF Mk-XII with Mode S transponder, automatic identification system, automatic deployable emergency location transmitter, solid state digital video recorder, pressure refueling system, 360-degree search-and-rescue homer with coverage from 110-410 MHz, electrical rescue winch with rescue basket for double-lift (250 kilograms/550 pounds), control grip (winchman mini-stick) in cabin for air-sea rescue, and upgraded IADS and automatic flight control system software.

Such an array of systems was hitherto seen only on heavier, multi-role helicopters of the Indian Navy. For instance, no light helicopter in the IN’s inventory ever featured a glass cockpit, surveillance radar or EO pod. The helicopter bears a “fully loaded” look. The maximum certificated all-up weight has been revised to 5,750 kg (12,675 lb.) from the earlier Mk-I variant of IN and ICG that weighed in at 5,500 kg (12,125 lb.).

Folded dimensions, a cumbersome blade-folding procedure, performance and maintainability issues plagued afloat exploitation of the eight limited-series production ALH Mk-I in naval inventory since their induction in 2003. The ICG holds four ALH Mk-I in its inventory, again with no integral ship flight.

Six of the 16 naval Mk-III ALH are to be equipped with an indigenous low frequency dunking sonar (LFDS) developed by Kochi-based Naval Physical and Oceanographic Laboratory. The sonar’s units are being produced by state-owned Bharat Electronics Limited with a host of sub-vendors downstream. Earlier this decade, the navy had offered a Mk-I naval ALH as test bed for developmental trials of the LFDS (this author was fortunate to participate in ground and flight trials of the LFDS).

Sources indicate that the IN views the coastal security ALH and Naval Utility Helicopter (NUH) programs differently. Seamless deck interface and a seagoing, light multi-role helicopter under 4.5 tonnes drives the navy’s flagship NUH program, sought to be delivered through a strategic partnership between an Indian OEM and foreign partner under the “Make in India” initiative.

HAL hopes to deliver five coastal security ALH Dhruv Mk-III helicopters by the end of November 2020, another nine by March 2021, and the balance 18 helicopters by September 2021 — a tough task given HAL’s order book and the changed situation post-Covid.