Two years ago, aircraft designers were invited to build an electric airplane that could fly at least 200 miles (322 km) in under two hours, using less than one gallon (3.8 liters) of fuel per occupant - or the electrical equivalent. Whichever plane performed best would win its makers a prize of US$1.35 million. That was the idea behind the Green Flight Challenge, a NASA competition that was managed by the Comparative Aircraft Flight Efficiency (CAFE) Foundation, and funded by Google. Well, the challenge wrapped up last week, with the winners being announced this Monday. Pennsylvania's Pipistrel-USA team took first place, for its Taurus G4.

The twin-fuselage aircraft has seating for four people, and a 145-kilowatt brushless electric motor that turns a two-bladed propeller, which is mounted between the fuselages. Its wingspan is approximately 75 feet (23 meters).

Out of 14 aircraft originally entered in the competition, it was one of three to make it through to the finals, held at the Charles M. Schulz Sonoma County Airport in Santa Rosa, California. Of those finalists, both the Taurus and the second-prize-winning eGenius doubled the required fuel efficiency, in that they each used the equivalent of just over half a gallon of fuel per occupant.

The Taurus specifically managed an equivalent fuel efficiency of 403 passenger miles per gallon (0.58L/100km) at a speed of 107 miles per hour (172 km/h) - according to Pipistrel team leader Jack Langelaan, that is twice as fast and efficient as a fully-occupied Toyota Prius.

"Two years ago the thought of flying 200 miles at 100 mph in an electric aircraft was pure science fiction," he stated. "Now, we are all looking forward to the future of electric aviation."

The video below was shot by a camera mounted on the Taurus G4.