Chandigarh: The recent crash of an indigenously developed Dhruv Advanced Light Helicopter (ALH) variant in Arunachal Pradesh, in which five Indian Army (IA) personnel died, raises serious reliability issues concerning the rotary wing platforms, which have recurringly been involved in accidents since their induction into service 2002 onwards.Operated by two experienced Army Aviation Corps (AAC) pilots with 1,800 flying hours between them, the 5.5 tonne twin-engine Rudra ALH Weapon Systems Integrated (WSI) Mk III that joined service in 2015, crashed in Arunachal’s Upper Siang district last Friday, on October 21, soon after putting out a distress signal to Air Traffic Control in the region.Also read: Pilot Killed as Army Helicopter Crashes in Arunachal PradeshPreliminary reports suggest that technical failure resulted in the accident, as the weather at the time was good, but an investigation into the crash is underway to determine its exact cause.Smoke billows after an advanced light helicopter of the Indian Army crashed at Migging in Upper Siang district of Arunachal Pradesh, Friday, Oct. 21, 2022. Photo: PTI.Some experts, however, speculated that controlled flight into terrain (CFIT) phenomenon, in which a pilot loses situational awareness, especially in mountainous terrain until it is too late, could have been responsible for the ALH’s crash.Consequently, as a precautionary measure, media reports revealed that all 330-odd ALHs in all its four variant types – developed and series manufactured by Hindustan Aeronautics Limited (HAL) – that were currently in service with all three-armed services and the Indian Coast Guard (ICG), were undergoing extensive checks, before receiving clearance to operate.These inspections included those of the ALHs ‘stress points’ like their engines, rotor blades and power transmission lines, amongst other onboard critical systems.According to official statistics presented in parliament by the ministry of defence since 2016, some 22 ALHs had crashed over the past two decades, in addition to many of them resulting in numerous emergency landings across the country.One such incident of an emergency landing in 2019 involved the Northern Army Commander Lieutenant General Ranbir Singh, who survived after ALH ferried him and seven others crash-landed in Jammu and Kashmir’s Poonch region, adjoining the disputed line of control with Pakistan. These crashes and mishaps, in turn, had led to the entire ALH fleet being periodically grounded for varying periods to complete rigourous checks on them before clearing them for take-off.ALHs fiasco in EcuadorHowever, not included in this tally of accidents are the four of seven ALHs that crashed soon after HAL exported them to the Ecuador Air Force (EAF) in 2008-09 for $42.5 million. These crashes led to Ecuador eventually terminating its ALH contract with HAL in October 2015 – in a major setback to what was then the first-ever major export of an indigenous military platform.At the time Ecuadorian defence minister Fernando Cordero had told reporters in the capital Quito, that two of these four crashes were due to “mechanical failure”, and that the remaining three Dhruvs had subsequently been grounded by the EAF. HAL, for its part, countered those claims by maintaining that “human error” was responsible for two of the four Dhruv crashes.The first Dhruv had crashed in Ecuador soon after its delivery to the EAF in 2009 whilst making a low pass at a military parade in Quito. The second accident occurred in February 2014, killing three of four people on board. These were followed by two back-to-back crashes within a fortnight of each other in early January 2015, which ultimately prompted the EAF against continuing to operate the ALHs.Conversely, HAL, which had completed Dhruv deliveries to Ecuador by 2012, contested Quito’s claims that it had failed to ship helicopter spares to the EAF on schedule.Also read: India Is ‘Sacrificing’ Soldiers by Operating Antique Helicopters, Army Wives Group Tells PMA HAL spokesman had then maintained that Dhruv’s service and maintenance were ‘exclusively’ the EAF’s responsibility, as the 24-month warranty period for the Bangalore-based public sector manufacturer to provide after-sales service support for the seven ALHs, had expired. But he had conceded that HAL was “more than willing” to offer the EAF “all and any” assistance that it required to keep the remaining three Dhruvs operational, a proposal Quito summarily rejected and scrapped the deal.The termination of the ALH buy by the EAF was, without doubt, a serious stumbling block for HAL in a field where flight safety remains the primary concern, and where stiff competition from established Western helicopter manufacturers in the US and Europe, endured.Industry sources told The Wire that Rudra’s crash in Arunachal too comes at a time when HAL chairman C.B. Ananthakrishnan claimed that the ALH and its Light Combat Helicopter derivative had immense potential for export.“Argentina is interested in the LCH, while the Philippines and Egypt have also expressed interest in the ALH,” Anantakrishnana told The Hindu at the recently concluded DefExpo-2022 at Gandhinagar. The HAL head added that his company’s annual ALH production capacity was 30 units at its Bangalore-based facility, while an equal number could be built at its newly instituted Tumakuru plant 70 km to the north, and which could be scaled up to double that number. Hence HAL, he noted, could ramp up its production of ALH and its variants to around 90 units a year, rendering the platforms viable for export.Approved for development in 1998 for induction primarily into the AAC, and with fewer numbers for the IAF, Rudra ALHWSI made its maiden test flight in 2007 and completed its final round of weapon trials four years later. The ALH had earlier conducted its maiden test flight in 1992 and was commissioned into service a decade later.Rudra, however, was inducted into the AAC in February 2013 after receiving initial operational clearance (IOC) from the Centre for Military Airworthiness and Certification in Bangalore to provide close air support (CAS) to ground formations against advancing enemy tanks, transporting troops and executing logistic, reconnaissance support and casualty evacuation missions.Powered by two full authority digital engine control (FADEC) 1,200hp Shakti engines, developed jointly by France’s Turbomecca-later Safran Helicopter Engines and HAL, the ALH, the MkIII version had 19 major improvements over the MKI/II versions. These included an all-glass cockpit, locally developed integrated architecture display, automatic flight control and countermeasure dispensing systems.The Rudra Mk III is also fitted with Saab’s integrated defensive aids suite (IDAS) from Sweden that include radar and laser warning missile detectors, infra-red jammers and targeting pods and chaff and flare dispensers designed by the state-owned Bharat Dynamics Limited. The platforms avionics suite integrates a global positioning system, Doppler radar, forward-looking infrared cameras, infrared friend of foe identification (IFF) system, radio altimeter and high and ultra-high frequency radio communication systems.Rudra’s pressurised, night vision goggle-compatible cockpit incorporates multifunction displays, dual and automatic flight control systems and nuclear biological and chemical (NBC) filters. The helicopters armament package comprises a forward-mounted French GIAT-Nexter 20mm M621 automatic cannon that can fire 750 rounds per minute to a range of 2,000m, four 70mm rockets provided by FZ of Belgium and MBDA’s Mistral-2 short-range air defence missile systems from France.The ALH Mk III that joined ICG service in early 2021, on the other hand, had a nose-mounted surveillance radar with 270-degree coverage capable of detecting, classifying and tracking marine targets, a multi-spectral electro-optic (EO) pod for reconnaissance and target acquisition and advanced transmitters, recording, anti-collision and communication systems.“Considering the government’s heightened pitch for exporting Indian defence equipment and platforms, the ALH still remains a work in progress and will have to earn all prospective importers’ trust in its operational efficiency,” said a senior industry official. Its reliability and operational safety will be the key to its success as a saleable product, he cautioned, declining to be identified.