Pilot error caused the chopper crash that led to Chief of Defence Staff General Bipin Rawat’s death last month, preliminary findings of the inquiry team investigating the matter have revealed.

“The accident was a result of entry into clouds due to an unexpected change in weather conditions in the valley. This led to spatial disorientation of the pilot resulting in a Controlled Flight Into Terrain (CFIT),” the team found after analysing the Flight Data Recorder and Cockpit Voice Recorder.

They also questioned all available witnesses to determine the most probable cause that caused the accident.

CFIT occurs when an airworthy aircraft, while under the complete control of the pilot, is inadvertently flown into terrain, water, or an obstacle.

According to the IATA (International Air Transport Association), the term refers to accidents in which in-flight collisions occur with terrain, water, or another obstacle without indication of loss of control.

Rawat along with his wife and 11 others, including his staff and crew members, had died in the Indian Air Force (IAF) helicopter crash in Tamil Nadu’s Coonoor on Dec 8 last year.

A Mi-17V5 helicopter was carrying Gen Rawat, his wife Madhulika, and 12 others from Tamil Nadu’s Coimbatore to the Defence Staff Services Colleges in Wellington.

Group Captain Varun Singh, a passenger on the chopper, miraculously survived the crash. He died of severe burn injuries a few days later.

The Tri-Services Court of Inquiry, led by the country’s top helicopter pilot Air Marshal Manvendra Singh, has submitted its preliminary findings.

The Court of Inquiry has ruled out mechanical failure, sabotage, or negligence as a cause of the accident.