New Delhi: Air force operations have been obstructed at Siachen Glacier, one of the world's highest battlegrounds, as Hindustan Aeronautics Limited (HAL) has not produced enough rotor blades critical for its light helicopters. The hardy fleet of Cheetah and Cheetal choppers serve as a lifeline for troops in high-altitude areas, especially for missions involving critical supplies and casualty evacuation. The specialised rotor blades give the French-origin light choppers enough lift to operate in harsh climatic weather.

With the French parent stopping manufacture of their blades since 2012, HAL had been using the last supplies of rotor blades that were ordered prior to 2012.

These choppers are produced by state-owned HAL and are being used by the Air Force for over 50 years. The IAF has warned about the future of the ageing fleet. HAL also expressed concern on its order for 10 Cheetal helicopters following its inability to manufacture the 85-series main rotor blades. With the French parent stopping manufacture of their blades since 2012, HAL had been using the last supplies of rotor blades that were ordered prior to 2012.

Last year, the defence ministry was informed that the 12 blades that the state-run manufacturer had produced — with the transfer of technology from Airbus Helicopters, the original manufacturer — demonstrated a high level of vibration and were hence unsuitable.

According to reports, the Air Force informed that the availability of the fleet could come down if replacements were not in place. The IAF's September 2015 order for 10 Cheetal helicopters was to be delivered last year, according to the original schedule.