Chopper Crash: Gen Bipin Rawat, his family members, and staff were aboard the chopper
Pilot error was the likely cause for the chopper crash that led to Chief of Defence Staff General Bipin Rawat's death last month, sources said Wednesday afternoon.
Sources said the Mi-17V5 helicopter carrying Gen Rawat, his wife Madhulika, and 12 other armed forces personnel - from the Sulur Air Force base in Tamil Nadu's Coimbatore to the Defence Staff Services Colleges in Wellington - crashed after a CFIT, or Controlled Flight Into Terrain, occurrence.
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 with terrain, water, or another obstacle occur without indication of loss of control.
The United States' Federal Aviation Administration says CFIT is '' ... an unintentional collision with terrain (ground, mountain, body of water, or an obstacle) while an aircraft is under positive control."
The critical distinction in such incidents is the fact the aircraft is under control of the flight crew.
Sources said the crash took place in cloudy weather and stressed that the aircraft - described by several ex-Army officers to NDTV as "very safe" - was not malfunctioning at the time of the crash.
A tri-services inquiry - led by Air Marshal Manvendra Singh, the country's top helicopter pilot - had been ordered to investigate the crash in Tamil Nadu's Nilgiri Hills on December 8.
The crash killed CDS Gen Rawat, his wife and 11 others. Group Captain Varun Singh, a passenger on the chopper, miraculously survived the crash only to die of severe burn injuries a few days later.
In the days after the crash mobile phone videos - taken by locals and shared by news agency ANI - emerged of the final moments of the chopper.
One clip shows a helicopter flying into thick cloud cover that emerged suddenly to hang over the Coonoor hills. A change in the engine sound can be heard.
Sources told news agency ANI the chopper was flying at a low altitude and that the crew decided to try and fly out of the cloud cover rather than trying to land and hit the ground in the process.
Gen Rawat was on his way to deliver a speech to students and staff at the DSSC when the chopper crashed, just seven minutes before it was due to land.
Gen Rawat, his wife, and all those on board were given funerals with full military honours, and thousands paid tribute to their memories, including the governments of major foreign powers.
With input from ANI