An artist's conception of the AeroMobil flying car. (Credit: AeroMobil) Flying cars are up against a wall — literally. Turning aircraft into street-safe machines requires manufacturers to prove their safety standards in crash tests. So at least one expensive prototype needs to get smashed to smithereens, while its dummy passengers survive. This is no small financial hurdle, and for a decade the industry has been just a few years away from getting models street-certified.