Self-driving cars have to worry about how to respond to road signs held by workers or to gestures of a police officer managing local traffic. They also have to be able to adapt to changing road conditions and visibility. But autonomous self-flying cars only need to worry about the vast sky, and take-off and landing. Those challenges are relatively straightforward. Autopilot technology and automatic landing systems have been around since the 1970s. Currently regulators are dealing with the massive growth in drones and drone regulations and legislation is being made, limiting the altitude at which they are allowed to operate. Flying cars do not need to take-off and land at existing airports, they can use any suitable runway, but in this case drone collision avoidance systems are needed, especially during take-off and landing outside of regulated airports.

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