October 11 , 07
Flying Car with Auto-Folding Wing Ready to Take Flight

"Founded in 2006 and called Terrafugia, their startup, based in Woburn, MA, recently produced the first automated folding wing for a light sport aircraft. (A light sport aircraft is a type of airplane deemed by the Federal Aviation Administration to be easier to fly and hence more accessible than regular private planes.) The wing, however, is just the first step toward an aero-auto hybrid that the company plans to call the Transition."

"This summer, the group demonstrated its folding wing at the annual AirVenture aviation festival in Oshkosh, WI. With more than 650,000 attendees, the festival is the most important event in experimental-aircraft aviation.

"Going into this, we knew our two biggest design challenges to make it practical would be the wings and the power train," says Anna Mracek Dietrich, an engineer at Terrafugia and the company's chief operating officer. "By validating the durability of the wing's construction and engineering, we've checked one major design challenge off of the list, and now our focus is on the second."

Previous prototypes of road-drivable aircraft have featured manually folding or detachable wings. But to allow for a seamless and quick transformation from plane to car and back, the Terrafugia team has devised a system that allows the pilot to enfold or extend the wings by pushing a button in the cockpit. Dietrich says that at Oshkosh, the researchers opened and closed the wings more than 500 times--the equivalent of three to five years of typical use--and that they're more than pleased with the wings' durability.

The wing features off-the-shelf electric actuators, but Dietrich says that the team had to design from scratch the mechanical linkages between the actuators and the rest of the craft. The group also uses dual electromagnetic locks to hold the wings tightly to the fuselage when they're enfolded.

"We're building the rest of the first vehicle now," Dietrich says. "Our schedule calls for us to start flight testing by the end of 2008, and so far we're on track for that." Read