Srinagar: The army and the air force’s Dhruv advanced light helicopter (ALH) fleets, grounded nearly four months ago following a fatal coast guard crash in Gujarat, have been declared airworthy, Hindustan Aeronautics Limited (HAL) said on Thursday.
The navy and coast guard’s ALHs are still grounded. The development comes at a critical moment as the Indian military readies plans to respond to Pakistan in the aftermath of the Pahalgam terror attack.
“The Dhruv ALH army and IAF versions are cleared for operations based on the recommendations of the defect investigation committee recommendations,” the state-run plane maker said.
A time-bound plan for the resumption of operations has been worked out with the users, it added.
Before the clearance came, the army had already begun flying its ALHs in Jammu and Kashmir to address urgent operational needs a day after the April 22 Pahalgam terror attack that killed 26 people.
HT had reported on April 2 that investigators were struggling to determine the root cause of the January 5 accident in which two coast guard pilots and an aircrew diver were killed.
A high-powered panel earlier found that a swashplate fracture caused the coast guard ALH crash at Porbandar in Gujarat on January 5. The reason for the breakdown of the critical component, which compromised the ability of the pilots to control the helicopter’s motion, was not immediately known.
Earlier HAL, which has designed and developed the ALH, involved Bengaluru-based Indian Institute of Science (IISc) to perform fatigue testing of a critical part in the twin-engine helicopter’s transmission system to get to the bottom of the matter.
The prolonged grounding of the workhorse fleet was a setback for the three services and the coast guard, which together operate around 330 ALHs.
A fleet-wide inspection conducted after the January 5 crash revealed that some navy and coast guard ALHs were facing the same problem — cracks in the swashplate assembly — and this could be linked to sustained operations in a saline environment.
HT was the first to report on February 4 that a detailed analysis by the Council of Scientific and Industrial Research-National Aerospace Laboratories (CSIR-NAL), Bengaluru, pointed to a swashplate assembly failure.
The ALH underwent a design review followed by a replacement of a defective control system only in 2023-24.
The helicopter has been involved in around 15 accidents during the last five years, putting the spotlight on its safety record.
The coast guard suspended ALH operations following an accident last September when a helicopter crashed into the Arabian Sea near Porbandar.
Then too, two pilots and an aircrew diver were killed. The grounding was for a one-time check. The three services did not ground their fleets then.
Last September’s accident, too, came after the design review that culminated in a critical safety upgrade on the ALH fleet, initiated by HAL. It involved installing upgraded control systems on the helicopters to improve their airworthiness. The comprehensive design review came after the ALH fleet was grounded several times in 2023 too after a raft of accidents called into question its flight safety record.