As the pilotless flying wing came in for a landing, winds suddenly picked up. Facebook Inc.'s Aquila drone -- powered by the sun and wider than a Boeing 737 jetliner -- struggled to adjust. Just before landing, part of the right wing broke off.
That inaugural 2016 flight proved an inauspicious beginning for Facebook's foray into internet-beaming drones, but perhaps a fitting one. Two years later, the company pulled the plug on developing its own aircraft.
Since then, companies such as Amazon.com Inc. and SpaceX have placed big bets on providing internet service around the world with thousands of small satellites. SpaceX's plans are set to jump forward Thursday with a launch of 60 internet-beaming satellites.
But don't count out solar-powered, high-altitude drones -- or giant balloons.
Advances in solar-cell and battery technology have made those technologies more feasible. Last month, Japanese telecommunications giant SoftBank Corp. said it would partner with California drone maker AeroVironment Inc. to build a drone capable of flying to the stratosphere, hovering around an area for months and serving as a floating cell tower to beam internet to users on Earth. Airbus and Boeing Co. are also working on their own versions of high-flying, solar-powered drones.
Driving these and other projects is the promise of 5G connectivity. That fifth-generation cellular technology, which is just rolling out, will increase download speeds dramatically. And proponents say its reliability should enable services such as self-driving cars and remote medicine.
Connecting remote users would enhance the market potential even more, said John Robbins, an associate professor of aeronautical science and coordinator of the unmanned aerial systems program at Embry-Riddle Aeronautical University.
"Increasing that footprint where people are able to access that information is extremely important," he said. "This is one way to do it."
The attraction of drones and balloons is they could cost much less than building cell towers in remote areas. And their location, closer to Earth than satellites, could offer faster response times, said Tim Farrar, president of TMF Associates, a telecommunications consulting and research firm in Menlo Park.
Industry experts estimate only 10% to 20% of the Earth's land area is covered by terrestrial cell towers. Mobile operators are interested in providing continuous service across the globe, particularly in light of the coverage needed for advanced, 5G applications. Drones could also be used in emergency situations in which cell towers have been destroyed or taken offline.