Chief of Defence Staff Gen Bipin Rawat, his wife and 11 others died after the Mi-17V5 helicopter came down in hills near Coonoor city on Wednesday morning.
One survivor is being treated for his injuries in hospital.
Gen Rawat, 63, was appointed India's first-ever Chief of Defence Staff in January 2019.
This brought together the Army, the Navy and the Air Force, and Gen Rawat had been in charge of a range of operations including in Indian-administered Kashmir.
