Several weeks ago, inventor and entrepreneur Martine Rothblatt, in collaboration with the engineering company Tier 1 Engineering, watched their creation take flight for about five minutes, piloted at an altitude of 400 feet at a peak speed of 80 knots.

“This was a proof of concept,” Rothblatt tells Fortune, explaining, “everyone told me this was impossible.”

While battery-powered drones are being flown around the world, no one is focused yet on using batteries to power a several-thousand-pound helicopter complete with a human driver and cargo in tow. These helicopters—and the batteries required to lift it—have been considered far too heavy.

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But going against the grain is de rigueur for Rothblatt. She founded Sirius Radio, car navigation company GeoStar, and biotech company United Therapeutics in an effort to commercialize a pill for her daughter’s disease, a rare life-threatening form of pulmonary hypertension.

Patients suffering from that disease also often require lung transplants. So Rothblatt next created a division of United Therapeutics that focuses on developing artificial and transplantable lungs from pig genetics.

Rothblatt envisions that the battery-powered helicopters will deliver the transplantable organs much more cleanly and quietly. Helicopters can burn 500 pounds of fuel every hour.

Rothblatt, who’s also a helicopter pilot, was inspired by Tesla to create the electric helicopters. She owns seven Tesla (TSLA) cars, and gave a presentation on the battery-powered helicopter concept this summer at Tesla’s Gigafactory party.

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Earlier this year, her team tore out the guts of an inexpensive helicopter, popped in batteries from electric motorcycle company Brammo, and inserted a YASA electric motor. On September 21, the group flew the helicopter for several minutes, using 1250 pounds of lithium polymer batteries to lift the 2500-pound helicopter.

The group says that the current set-up can power the helicopter for about 20 minutes. Rothblatt’s company Lung Biotechnology funded the project, which cost less than $1 million.

Rothblatt tells Fortune that the next step is to design a battery pack and helicopter specifically for an electric helicopter. That likely means lightening the load considerably.

Tesla took a similar approach to building its first car, the Roadster, and designing its follow-on car the Model S. The entrepreneur says she’s in the midst of talking to helicopter makers to choose the vendor.

If the group develops solid battery-powered helicopter tech, Rothblatt says they’ll probably license it to other companies. And thus Rothblatt, who is also transgender, will have tackled yet another new vertical, from satellite tech, to biotech, to genomics, and now into the electric vehicle industry.

While Tesla wasn’t involved in the project, Tesla CEO Elon Musk has long talked about his interest in an electric flying vehicle that can take off and land vertically.