Hindustan Aeronautics Limited (HAL) on Sunday underlined the critical importance of strict maintenance practices for the continued airworthiness of the Advanced Light Helicopter (ALH) Dhruv fleet, a day after the Indian Army ordered a one-time safety check across all units following a defect in the chopperโs tail drive shaft (TDS).
HAL said it has deputed expert teams to work closely with the Army to ascertain the root cause of the defect, which involves a vital transmission component that transfers engine power to the tail rotor and directly impacts the directional stability of the helicopter.
โOne-Time Check (OTC) is a routine maintenance practice issued subsequent to a defect, in this case, of the TDS. HAL reiterates that maintenance aspects are critical to the continued airworthiness of helicopters and emphasises that all maintenance directives must be followed scrupulously,โ the state-owned aircraft maker said in its statement.
The clarification came after Hindustan Times reported on September 6 that the Army had recorded an incident involving damage to an ALHโs TDS during flying operations on September 4. The Directorate General of Electronics & Mechanical Engineers (Aviation) immediately directed all ALH units of the Army, Air Force, and Navy to conduct fleet-wide checks.
The Army and Air Force together operate about 300 ALHs, while the Navy and Coast Guard operate around 30. In total, Indiaโs armed forces and security agencies fly more than 330 Dhruv helicopters, which have collectively logged over 4.5 lakh flying hours in diverse terrains, from Himalayan high-altitudes to coastal belts.
The ALH fleet was only cleared for flying in May this year after being grounded for several months following a fatal Coast Guard crash in Porbandar on January 5 that killed two pilots and a diver. That accident was linked to a swashplate fracture, though the root cause of the defect remains under investigation.
The Dhruv has faced repeated safety concerns over the years, being involved in around 15 accidents in the last five years. The helicopters underwent a design review and control system upgrades in 2023โ24 after multiple groundings.
Despite setbacks, HAL defended the fleet as one of its flagship indigenised platforms. โThe ALH has flown extensively in challenging terrains and continues to be trusted for high-risk rescue operations, including the Armyโs ongoing flood relief missions,โ the statement said.
The latest checks come even as HAL continues separate defect investigations into the Navy and Coast Guardโs ALHs, which have remained grounded for over eight months after the January crash.