I applied online. I interviewed at Defence Research & Development Laboratory (Hyderābād) in July 2018
Interview
Extensive written interview, which involves derivation, and solving mathematical problems and concepts for various engineering subjects. There will be 5-6 subject matter experts in front of you and it will be a Panel interview. Scientists are very friendly and will give you clues as well, it is totally up to you to grab and excel.
Interview questions [1]
Question 1
Non Isotropic material stress and strain difference. Thermodynamic cycles, RAC, Differentiation, etc.