Is it a car? Is it a plane? Actually it’s both. The first flying automobile, equally at home in the sky or on the road, is scheduled to take to the air next month.

If it survives its first test flight, the Terrafugia Transition, which can transform itself from a two-seater road car to a plane in 15 seconds, is expected to land in showrooms in about 18 months’ time.

Its manufacturer says it is easy to keep and run since it uses normal unleaded fuel and will fit into a garage.

Carl Dietrich, who runs the Massachusetts-based Terrafugia, said: “This is the first really integrated design where the wings fold up automatically and all the parts are in one vehicle.”

The Transition, developed by former Nasa engineers, is powered by the same 100bhp engine on the ground and in the air.

Terrafugia claims it will be able to fly up to 500 miles on a single tank of petrol at a cruising speed of 115mph. Up to now, however, it has been tested only on roads at up to 90mph.

Dietrich said he had already received 40 orders, despite an expected retail price of $200,000 (£132,000).

“For an airplane that’s very reasonable, but for a car that’s very much at the high end,” he conceded.

There are still one or two drawbacks. Getting insurance may be a little tricky and finding somewhere to take off may not be straightforward: the only place in the US in which it is legal to take off from a road is Alaska.

Dietrich is optimistic. He said: “In the long term we have the potential to make air travel practical for individuals at a price that would meet or beat driving, with huge time savings.”

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