The crash of an Advanced Light Helicopter (ALH) DHRUV near Kishtwar, Jammu and Kashmir, has again raised questions on metallurgical issues with a critical component, the control rod, on board the copter.

A team of the three armed forces personnel, which has been consulting with HAL, wants that a control rod which is in the gearbox and is a key component in transferring power from the two engines of the copter to its overhead rotors need to be replaced in some of the copters.

The control rod is made of aluminium. The armed forces have suggested that the rods be made of a stronger material such as steel. Special checks are in place to inspect the control rod after every 100 hours of flying.

Failure of control in the gearbox results in the copter not responding correctly to the pilot’s inputs. As a result, it becomes impossible to control the copter, sources say. Pilots flying DHRUVs have reported “sudden loss of power”.

Thursday’s incident was the tenth involving a crash or an emergency landing in the past three years since May 2020. This was the third incident in the past two months. In all, 284 DHRUV variants are in operation.

10 incidents in three years

Crashes

May 9, 2020: Army aviation, north Sikkim; five injured
Jan 25, 2021: Army aviation, Kathua, J&K; one pilot dead
August 3, 2021: Army aviation, Punjab; two pilots dead
Oct 22, 2022: Army aviation, Migging, Arunachal Pradesh; five, including two pilots, dead
May 4, 2023: Army aviation, Kishtwar, J&K; one dead, two pilots safe

Emergency Landings

Oct 8, 2020: Near Saharanpur; Indian Air Force; no injury
March 6, 2021: Army aviation near Kheda, Gujarat; two officers on board; no injury
Jan 2, 2022: Army aviation near Jind, Haryana; no injury
March 26, 2023: Coast Guard at airport, Kochi; no injury
March 8, 2023: Forced ditching at sea; Indian Navy; no injury