Maharshi Bhardwaj had written Vymaanika-Shaastra, which was discovered in a temple in India. This book was written 400 BC and talked about the operation of ancient vimanas, how they steered, propelled, how they took precautions for long flights, how they protected airships from storms and lightning, how they switched the drive to solar energy and other free-energy sources. The vimanas in those days took off vertically, and he talks about at least 70 authorities and 10 experts of air travel.