Elon Musk: 'We could definitely make a flying car'

Elon Musk, imaginative billionaire and CEO of SpaceX and Tesla Motors, said Monday at the British launch of the Tesla Model S that he often thinks about building a car that can fly.

"We could definitely make a flying car -- but that's not the hard part," Musk told the Independent. "The hard part is, how do you make a flying car that's super safe and quiet? Because if it's a howler, you're going to make people very unhappy."

Musk, who described any flying car project as "just for fun," said he had plans to build a submarine car inspired by the vehicle driven by Roger Moore's James Bond in The Spy Who Loved Me.

"It can transition from being a submarine to a car that drives up on the beach. Maybe we'll make two or three, but it wouldn't be more than that. It's not like we'd sell it, because I think the market for submarine cars is quite small," he said.

Terrafugia Inc., a Massachusetts company founded by MIT graduates, has been already working on a flying car called the Transition. It's scheduled for a 2016 debut.