It might not the most elegant-looking thing on the road or in the sky, but an automobile-airplane hybrid that’s being called the world's first practical flying car is almost ready to spread its wings.

The two-passenger Transition will go on sale in the U.S. next year at an estimated price of $400,000, according to Terrafugia, the Woburn, Massachusetts-based firm that makes it.

The Transition has four wheels, folding wings and a rear-mounted “pusher” propeller. Powered by a four-cylinder hybrid-electric engine, it can fly 100 miles an hour at altitudes of up to 9,000 feet, with a flying range of 400 miles. There are controls for both flying and driving: for the roads, conventional brake and accelerator pedals and a steering wheel; for flying, the usual yoke and rudder pedals.

The vehicle converts from driving to flying mode in less than a minute, according to Terrafugia. But don’t expect it to get you out of a traffic jam. Though it’s the first vehicle certified to drive on U.S. roads and fly in U.S. skies, it can take off and land only at airfields — and you’ll need a pilot's license.

Many flying car prototypes have been built in recent decades, but none has proven practical enough to become a full-fledged production vehicle. The Transition is designed mainly for light aircraft owners who don’t want to get stuck when bad weather makes flying impossible, or who want to avoid airfield parking fees and fuel costs, according to Terrafugia. The vehicle runs on ordinary premium gasoline and can be kept in a garage at home.

But the company, now owned by Chinese car maker Geely, also hopes the Transition will attract people who are new to private aviation. “We would like people who never thought of becoming a pilot before to consider it because, hey, it’s a flying car,” Carl Dietrich, Terrafugia’s founder, told Smithsonian Air and Space magazine.

Terrafugia was founded in 2006 with a plan for a “flying SUV” that earned Dietrich a prestigious technology prize. But with recent advances in autonomous passenger drones — electrically powered “air taxis” that take off and land vertically without a runway — experts say vehicles like the Transition are likely to be a niche product.

“The world changed while they were working on that vehicle,” says Richard Anderson, an aerospace engineering professor at Embry-Riddle Aeronautical University in Daytona Beach, Florida.

Investors worldwide are pouring billions of dollars into the development of air taxis, with manufacturers like Airbus and Germany’s Volocopter claiming to be well on the way to bringing the vehicles to market. “The business case is absolutely crystal clear, and the technology is here,” Anderson said.

Terrafugia said it is developing its own vertical-takeoff-and-landing passenger vehicle, dubbed the TF-2, that could take to the skies as a piloted aircraft in 2023. That’s likely to be several years before the first self-piloted air taxis get approval from the Federal Aviation Administration, Anderson said.

“These vehicles are things that were never seen before, so there's a learning process,” Anderson said of the FAA. “Even if they are willing to embrace the technology, they have to understand it before they're going to let it fly over our heads in a city.”

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