A drone is flown for recreational purposes in Syosset, New York. Bruce Bennett | Getty Images

A matter of seconds

For the best shot at saving lives, organs must be transplanted as quickly as possible after they are removed from donors' bodies. But organs can't be transplanted until they're transported to where they're needed — whether it's across town or across the country. And the usual methods of transporting organs, which include motor vehicles, helicopters and airplanes, have significant limitations. "Charters are too expensive, commercial aircraft is too slow and small aircraft at inconvenient hours are dangerous to transplant teams," said Scalea, who was also a member of the surgical team that transplanted the kidney at the medical center. Drone delivery could cut the time organs spend in transit by 70 percent, he added. Experts say that could make a big difference. "In many circumstances — say, a mother hemorrhaging after childbirth — a few seconds or minutes can mean the difference between life and death," Graboyes said in the email. "Across rugged terrain, traffic-clogged cities, icy roads or flooded regions, a drone may become the quickest and surest way to get medical goods to where they're needed."

Not your basic drone

The autonomous drone used for the pathbreaking flight isn't of the sort flown by hobbyists. In addition to a pair of nested boxes to hold an organ, the eight-rotor drone carries sophisticated communications gear and backup batteries and powertrains to make sure it stays aloft even if some components fail. There's also a parachute — so the drone and its life-saving cargo can reach the ground safely in the event of a major malfunction. "We had to create a new system that was still within the regulatory structure of the FAA, but also capable of carrying the additional weight of the organ, cameras and organ tracking, communications and safety systems over an urban, densely populated area," Matthew Scassero, director of the university's unmanned aerial vehicle test site in California, Maryland, said in a statement. "There's a tremendous amount of pressure knowing there's a person waiting for that organ, but it is also a special privilege for us to be a part of that critical link." Scassero predicted in an email that drones would be used to deliver organs on a "fairly regular basis in some locations" within two to three years and that organ delivery by drone would become routine within the next decade.

Remaining obstacles