US military will soon have a new solar-powered unmanned spy aircraft called Solar Eagle.The aircraft, being built by Boeing is designed in such a way that it can soar in the upper atmosphere for years, constantly sending surveillance and intelligence information back to the ground. Unmanned spy aircraft can fly non-stop for more than five years.The US military has already given Boeing an 89-million dollars contract to develop a Solar Eagle demonstrator which will make its first flight in 2014.