Hindustan Aeronautics Limited (HAL) conducted extensive tests on the Navy and Coast Guard's Dhruv Advanced Light Helicopters (ALH) off the coast of Visakhapatnam over a continuous period of two weeks in August 2025.

The objective of these rigorous trials was to collect critical data aimed at identifying and fixing persistent flaws that led to the grounding of the naval and coast guard Dhruv fleet approximately seven months ago following a fatal crash of a Coast Guard ALH near Porbandar, Gujarat, on January 5, 2025.

The test operations involved flying instrumented Dhruvs—one each from the Navy and Coast Guard—equipped with sensors and gauges to monitor key components of the helicopter's integrated dynamic system. This included close scrutiny of the transmission system, gearbox, rotor hub, and the loads these subsystems endure in different maritime operating environments and weather conditions.

The ALHs were flown from warships in the demanding maritime environment off Visakhapatnam to simulate real operational stresses and capture a comprehensive data set that reflects the challenges faced by naval aviation in saline and harsh marine conditions.

HAL’s efforts to collect this data are part of a broader investigation overseen by a Defect Investigation Committee (DIC) comprising officials from the Centre for Military Airworthiness and Certification (CEMILAC), the Directorate General of Aeronautical Quality Assurance, and HAL.

The collected data is being analysed by the Rotary Wing Research & Design Centre and findings are expected to be submitted to the committee by the end of August 2025. These steps follow earlier research involving the Indian Institute of Science (IISc), which conducted fatigue testing on the helicopter’s swashplate assembly—a critical component suspected of failure that triggered the January crash by causing loss of control.

The Navy and Coast Guard operate around 30 Dhruv ALHs that have faced a recurring issue with cracks in the swashplate assembly, apparently aggravated by prolonged operations in maritime conditions—unlike the Army and Air Force's Dhruvs, which were cleared for flight in May 2025 after passing comprehensive safety checks. The investigation follows a history marked by several accidents over recent years, spotlighting safety concerns with the naval and coast guard Dhruvs in particular.

This comprehensive testing and data collection initiative by HAL is a crucial step toward pinpointing the exact root cause of the faults and ensuring necessary technical corrections can be implemented. 

Only after the defect investigation committee reviews the final analysis and proposes remedial measures will the fleet be considered for re-certification and eventual return to operational status. The test campaign off Visakhapatnam thus represents a critical phase in the effort to restore confidence in the safety and reliability of the Dhruv helicopters operated by India's Navy and Coast Guard, ensuring their readiness for the challenging maritime operational environment.

IDN (With Agency Inputs)