A Silicon Valley company reportedly backed by Google co-founder Larry Page has released a video of an airborne prototype of a flying car that it has been developing, promising deliveries of the "personal flying machine" later this year. The video, released on Monday by the Kitty Hawk company, shows the single-seater Flyer taking off from a lake and hovering above the water. It is propelled by eight rotors and takes off and lands vertically, like a helicopter. A pilot's licence is not required, and a person just needs two hours' training, the company says.