One shred of solace that surfaced as hurricanes and tropical storms pummeled Texas, Florida and Puerto Rico last fall was the opportunity to see drones realize some of their life-saving potential.

During those disasters unmanned aircraft surveyed wrecked roads, bridges and rail lines. They spotted oil and gas leaks. They inspected damaged cell towers that had left thousands unable to call for help. “Drones became a literal lifeline,” former Federal Aviation Administration chief Michael Huerta told the agency’s drone advisory committee in November.

The drones used needed a special exemption from a set of FAA rules, known as Part 107, that normally require small drones to fly below 400 feet, stay within the operator’s visual line of sight and avoid populated areas.

These regulations make it hard for commercial drones to operate in the United States. But last October the Department of Transportation took a big step: It invited state and local governments to partner with universities and companies on tests to speed the integration of drones into the national airspace. The FAA is reviewing 149 proposals and plans to choose five to 10 by mid-May.

The proposals cover a wide range of applications. Many of them are health-related. “I am confident that one-half or more of all the applicants have put some element of medical support in their proposal,” says John Walker, a Lancaster, Penn.-based aerospace consultant who spent 32 years at the FAA before co-founding the Padina Group, Inc in 2006.

Walker believes early public acceptance of drone delivery networks in urban areas will revolve around hospitals. And once drones can safely and reliably carry blood and medical supplies, that will pave the way to other kinds of drone deliveries. “That linear network where drones can operate between hospitals … would also have Amazon and anyone else that could meet the requirements to operate,” Walker says.

Several companies have approached governments in developing countries about performing medical deliveries in areas with great need, poor roads and less crowded skies.

In late 2016 Zipline, a San Francisco Bay Area-based robotics startup, set up distribution centers in Rwanda, where its drones had made more than 1400 flights carrying on-demand blood and emergency supplies over 62,000 miles as of last fall. This year the company will expand its medical delivery operations by launching a second base in Rwanda and new service in a larger neighboring country, Tanzania.

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