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Leveraging the Space Above Our Heads and the Emergent eVTOL Market

Wednesday, December 6, 2017

Getting stuck in traffic isn’t just a nuisance. On an aggregate level, traffic can have major financial impacts on cities and countries. Globally, 2 to 4 percent of gross domestic product is lost every year due to congestion, according to Carl C. Dietrich, PhD, co-founder and chief technology officer of Terrafugia.

One solution to alleviating traffic may be right above our heads.

“People have been flying small aircraft for a hundred years,” Dietrich said during his recent talk as part of the U.S. DOT Volpe Center’s speaker series The Ongoing Transformation of the Global Transportation System. “Why don’t we take better advantage of the fact that we have this great resource right above our heads?”

Carl Dietrich and his company have developed a small airplane that can also be driven on roads and is part of a larger trend of investment in flying-vehicle technologies. (Volpe photo)

A Street-Legal Airplane

Barriers to entry have kept many people away from flying small aircraft, Dietrich said. Pilots need lots of training. Aircraft are very sensitive to weather. There are high ownership costs and long door-to-door travel times, and many general aviation airports have limited ground mobility.

But Dietrich and his company have developed a small airplane that can also be driven on roads—in contrast to a flying car—that is part of a larger trend of investment in flying-vehicle technologies, and that addresses barriers to entry for potential pilots.

“We have this tremendous infrastructure in the United States of over 5,200 public use airports, on average one within a half-hour drive of wherever you are in the country,” Dietrich said. “Most people don’t even know that they exist. It’s one of the first questions that I always get: ‘Can I just take off and land from the street?’ No, you go to one of these places—but they’re all over the place.”

Safe as a Bicycle?

Flying commercially is the safest way to travel. Flying a small aircraft is less safe.

“Statistically right now, flying by general aviation aircraft is safer than riding a motorcycle, but it’s not as safe as riding a bicycle, in terms of fatalities per mile,” Dietrich said.

Ensuring that general aviation pilots and their passengers feel comfortable and safe is a critical baseline for attracting new pilots. Because loss of control is the biggest cause of general aviation crashes, Terrafugia’s vehicle is purposely simple to operate and includes haptic stall warnings so that pilots are more likely to notice and correct the stall.

“There’s a lower pilot workload: no mixture, no carb heat, no retractable gear, no prop pitch control, no spoilers, no flaps,” Dietrich said. “This is basically as dumb, simple, as flying gets. This is Piper Cub simple. This is stick, rudder, throttle.”

The Potential for eVTOLs to Alleviate Car Traffic

The Federal Aviation Administration has not certified any electric vertical takeoff and landing (eVTOL) aircraft, Dietrich said. But, Dietrich and his company are informing industry standards for certifying electric motors for flying vehicles, like eVTOLs, because the potential market for eVTOLs could be large.

From a technological and performance perspective, it seems feasible that eVTOLs could transport people comfortably, Dietrich said. Major challenges would exist around infrastructure—building enough vertiports to meet demand—air traffic control in urban areas, and community concerns about noise.

“The potential market is truly huge, and the potential benefit from enabling that market in terms of global GDP, this is the kind of thing that could actually change things by a percentage point, and that kind of thing is very, very exciting,” Dietrich said.

Video Highlights

Watch video highlights from Carl Dietrich's talk at the Volpe Center.