The U.S. Federal Aviation Administration (FAA) has approved flight testing of mini-versions of Terrafugia’s TF-X flying car in U.S. airspace. The FAA has granted Terrafugia, a small Boston, Massachusetts-based aircraft company, exemption to conduct tests with an autonomous drone version of its proposed TF-X flying car.

The company now appears set to be the first in the world to produce flying cars.

Terrafugia first announced plans to build and market a flying car in 2013. The company unveiled an upgraded prototype of their futuristic TF-X — a four-seat, hybrid electric, semi-autonomous, vertical takeoff and landing (VTOL) flying vehicle — earlier this year.

The company has said it will commence testing a miniature drone or small Unmanned Aircraft Systems (sUAS) version of the TF-X flying car prototype in the coming months. The model to be tested in U.S. airspace is only about one-tenth of the size of the prototype.

According to Aero News Network, testing a miniature version of the full-sized prototype is crucial to the development of the world’s first street-legal flying car. It grants engineers flexibility they need to fast-track research and development for the consumer market version of the prototype with unique engineering and unconventional configuration.

Terrafugia’s engineering team will test the hovering capabilities and gather data on flight capabilities of the miniature model.

“Because of the unconventional configuration of the TF-X, it is vital to achieve sustained, stabilized hovering with smaller models before developing a full-size TF-X prototype,” Aero News Network reports.

The company described the exemption granted by FAA to test models of the TF-X in U.S. airspace as a “significant milestone.”

The FAA exemption was granted under the condition that Terrafugia’s flight test team will work in close partnership and communication with aviation authorities. FAA regulations required Terrafugia to obtain special permission before commencing commercial R&D tests. The company’s flight test team is required to maintain constant contact with relevant authorities to ensure compliance with all relevant airspace regulations.

The engineers were granted permission to conduct tests at altitudes up to 121 meters (400 feet) and at speeds up to 160 km/h (100 mph).

In a statement to the media, Terrafugia explained, “Extensive sub-scale flight testing of sUAS [small Unmanned Aircraft Systems], along with wind tunnel testing and aerodynamic simulation, are key to refining the vehicle’s design.”

As of last week, company engineers were busy constructing the TF-X sUAS and fine-tuning details of test plans. It is expected that the final version of TF-X for the consumer market will be a fixed-wing, street-legal, four-passenger hybrid vehicle with rechargeable batteries. TF-X flying car owners will be able to charge their batteries with the vehicle’s engines and at plug-in stations.

Carl Dietrich, CEO Of Terrafugia (Photo By Jemal Countess/Getty Images)

The flying car is expected to be marketed with a cruising speed of 322 km/h (200 mph) and a flight range of about 800 kilometers (500 miles). The car will be able to take off and land without need for runway space. The car will be able to land at pre-approved sites under favorable weather conditions.

Although the flying car will be larger than the average car, it will be able to drive on roads and fit into normal-sized garages.

The flying functions will be controlled by a computer. This means that much of the flying functions will be under autopilot control, and drivers will be able to use the flying car after minimal pilot training.

When the driver switches to flying mode, the wings will unfold, revealing electric motor pods that power up the car and provide lift, according to Science Alert. Thrust will be provided by two propellers that fold back when the car is cruising.

Terrafugia said it expects it would take about eight to 12 years to fully develop the flying car and obtain final approval for the consumer market.

Competing ongoing projects include the French government sponsored “Xpolair,” a small drone-like commuter plane. A half-size prototype of the aircraft was unveiled at the Paris Air Show in 2013. The full-size model is expected to be unveiled in 2017.

But unlike TF-X, Xplorair is more like a mini-drone than a car and seats only one passenger.

[Photo by Jemal Countess/Getty Images]