On 8 December 2021, Chief of Defence Staff General Bipin Rawat, his wife Madhulika Rawat, Brigadier Lakhwinder Singh Lidder and 11 other defence personnel were killed in a helicopter (Mi-17 V5) crash at Coonoor in Tamil Nadu. Now, the India Meteorological Department (IMD) has confirmed persistent low clouds coupled with high humidity and visibility of 1-2 km at the site of the crash.
IMD submitted a report along with satellite images of the weather conditions on the day of the crash, to Tamil Nadu police. The report mentions, “the humidity was hovering around 95% with wind speed of 05-10 knots at an altitude of 1.5 km calculated on the basis of numerical weather prediction model analysis”. The IMD report said the weather was partly cloudy with light rain at isolated places along the Western Ghats. The air temperature was in the range of 14-16 degree Celsius and no fog was reported by the part time observatory at Coonoor where only two observations were recorded daily.
On 8 December 2021, the helicopter took off from the Sulur Air Base in Coimbatore and was flying to the Defence Services Staff College, Wellington, but crashed on the way. On the complaint lodged by the Coonoor Village Administrative Officer C. Raul Retina, the Upper Coonoor police registered a case under Section 174 (Unnatural death) of the Criminal Procedure Code. Considering the sensitive nature of the incident, the State police appointed an officer in the rank of Additional Superintendent of Police to investigate the case. While the police were probing all angles and even conducted combing operations in the vicinity of the crash site and line of landing, the prime suspicion was about bad weather since a video shot by some tourists showed the ill-fated chopper flying into clouds moments before it came down.
Soon after the incident, it came to light that IMD had no role in preparing the helicopter flight plan of that day. Rather, the Indian Air Force relied on its own weather forecast system. After coming to know that IMD did not issue any report on weather that day in connection with the short flight, investigators formally wrote to the authorities concerned requesting for satellite images of the weather.