Facebook wants to beam Internet to the nearly two-thirds of the planet that don’t have access. Now, the company has revealed some astonishing details about how it plans to do it.

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Yael Maguire, the engineering director at Facebook’s Connectivity Lab, said the drones in development will each be the size of a Boeing 747 jumbo jet and stay in the air for years.

“In order for us to fly these planes—unmanned planes that have to fly for months, or perhaps years at a time—we actually have to fly above the weather, above all airspace,” Maguire said during an interview at the Social Good Summit in New York City on Monday. “That’s between 60,000 and 90,000 feet. Routinely, planes don’t fly there, and certainly not drones.”

To keep the drones in the air for months or years, Facebook plans to use solar power. Solar energy will allow the planes to keep flying while they beam Internet around the world and use lasers to communicate with systems on the ground.

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Needless to say, the technology isn’t quite there yet. The Connectivity Lab has developed a timeline that aspires to get the first plane in the air by 2015. After that it’ll still be an optimistic three to five years of testing before the aircrafts will begin to provide Internet.

“We have to push the edge of battery technology, of solar technology, of composite technology,” said Macguire. “There are a whole bunch of challenges that our team is super excited to work on.”

Photo by Aero Icarus