The collection hardware that aerospace engineer Kyle Clark has assembled to further his quest for electric vertical-lift aviation would make any proper gearhead or technophile hyperventilate. In one corner of the hangar that will soon become the headquarters for Beta Technologies in Burlington, Vermont—sitting behind an old F-4 Phantom being renovated by the Air Force Reserve—is a vintage Enstrom 28FX helicopter Clark is converting to battery power to evaluate the direct-drive electric motors being installed in the company’s new air taxi prototype. Down the street, at its current HQ, a cabinet of 3-D printers cranks out prototype models and parts, while a collection of battle-scarred flying models of past and future iterations of Beta’s air taxi hang from the walls and ceilings. Across the room, a computer running the high-fidelity flight simulator X-Plane—its creator, Austin Meyers, is part of the team—provides engineers and pilots the chance to evaluate the flight characteristics of the forthcoming aircraft, via a cabin mockup of two seats and three screens.
In another location down yet another street, Beta engineers are working on a solar- and grid-powered recharging pad for e-VTOL aircraft—the electric vertical takeoff and landing vehicles Uber and others are betting will start a mobility revolution within the next decade. The idea, Clark says, is that such stations could be set up in key areas so that electric aircraft can recharge between and during missions, even in remote locations.
“The re-charging pad is modular and built from recycled shipping containers and reused aircraft batteries,” he said, noting that the stations can be customized to the individual location. “Each shipping container has a specific purpose. Some contain batteries, some contain overnight hotel units, some are maintenance containers, and others contain a control center and pilot briefing room.”
But it’s actually across Lake Champlain where the hardware gets really interesting. There, at Plattsburgh International Airport—formerly Plattsburgh Air Force Base—the company stores and tests its actual aircraft, the Ava XC. This 4,000-pound, eight-motor, eight-propeller battery-operated e-VTOL aircraft has been in secret development for two years, but was revealed to The Drive during a visit last week. The aircraft uses those eight rotors to allow vertical takeoffs and landing by pointing them 90 degrees up; when pivoted forward, they provide thrust while the 35-foot wing generates lift. The aircraft sits high on tall landing gear, which provide the ground clearance necessary when the propellers pitch forward. It is so far the heaviest known e-VTOL to fly, with more than 170 tests under its belt to date.
Not only did the company come out of stealth mode this week, but it revealed its funding source and an ambitious demonstration scheduled for this spring or summer. Though the amount invested in Beta remains secret, Clark revealed that his company is funded by United Therapeutics, which is developing manufactured organs for human transplant. Led by technology entrepreneur Martine Rothblatt, founder of SiriusXM satellite radio, the company expects to begin manufacturing its organs around 2024–about the same time that Clark says the production version of his aircraft will be ready.
Rothblatt sees e-VTOL as the most efficient and economical way to transport organs on-demand. The technology is very close to ready, she said, with battery capacity improving annually.
“We’ve seen seven percent improvements in energy density every year for the past several decades,” she said. “We need 300 watt-hours per kilogram in order to reach a range of 250 nautical miles, which is what I’m asking for, and it’s a no-brainer to see that we’ll be there in just a few years.”
Clark—who’s no stranger to Vermont’s chill, having once played minor league ice hockey—began his quest even before meeting up with Rothblatt, through work dating back to his college days at Harvard and stretching through a variety of engineering and software startups across the last 15 years. He committed to building Ava when Beta formed in 2017, as a way of “opening up a conversation” about electric aviation. The plan was to fly the aircraft across the country as a way of exposing all the challenges and associated with the work, from performance to regulatory to practical matters such as charging. He assembled a team that included veterans of GE Global Research, Scaled Composites, Tesla, and multiple technology and engineering firms. He even struck up a friendship with Segway inventor Dean Kamen that saw the latter become one of Beta’s key advisors.
Now, the vision is all coming together in Burlington and across the lake in Plattsburgh. During several tests last week, Clark flew Ava up and down the 12,000-foot runway, with chase vehicles in hot pursuit. It flew confidently and capably—and much more quietly than I expected. It’s no turbine-powered chopper, but a serene, steady flying machine.
At the moment it appears that Beta is a solid front-runner in the race to e-VTOL glory—though other companies are being as secretive as Beta previously was about their own status. Though the development of the final production aircraft will focus on the specific needs of Rothblatt’s work, Clark is free to also pursue the air-taxi market with his aircraft, as it could easily serve both roles.
Regardless of the many specific potential uses, he’s passionate about the simple advantages brought by electric aviation. The biggest is reliability: “With many fewer moving parts running at much lower temperatures, electric motors will go for three to 10 times longer before requiring an overhaul,” he said. Another is efficiency. Internal combustion aircraft operate at between 20 and 30 percent efficiency, while electric motors reach 90 to 99 percent efficiency, meaning they can be operated far more economically without emitting any pollution from the aircraft itself.
Finally, there’s the pure performance advantage. “Electric motors put out a constant torque across all speeds,” Clark said. “This enables them to be used in a distributed propulsion configuration where the flight controller can demand and expect instantaneous thrust adjustments at any power level.”
The result: Ultra-precise control no matter the speed or attitude. In fact, e-VTOL aircraft could safely cut power completely—such as to avoid a collision—go into freefall, then restart and recover before hitting the ground. Though such a capability is unlikely to ever be used, as the air-taxi market takes off and similar aircraft enter the skies by the thousands in coming decades, it’ll be a good trick for one to have up the sleeve—just in case.
The upcoming cross-country flight is meant as both a discovery process—to learn about the capabilities and uncover unknowns—and a demonstration of the technology. To pull it off, Beta will rely on one additional piece of very cool hardware in the hangar: a 1982 Eagle bus. Formerly a musician’s touring vehicle, Clark converted it to a mobile charging platform for Ava. It now has batteries, solar panels, and generators, as well as an expandable landing pad on the roof. Inside, there are bunks and a lounge area for team members to track the flights and troubleshoot along the way.
Around the time of the cross-country journey, Clark will also reveal the final configuration of the production version. Don’t expect it to look like Ava, though: It will be completely different from her set-up, as well as faster and capable of flying much further, up to 290 miles—with no bus necessary.