The Indian Army has ordered radar-invisible bomb-dropping drones built by two 20-year-old engineers inside a hostel room of BITS Pilani's Hyderabad campus. The unmanned aerial vehicle is capable of flying at a speed of 300 kmph. "I wrote cold mails to whoever I could find, luckily a colonel responded and called us to Chandigarh for demo," Jayant Khatri told TOI.