Facebook wants to place internet drones over specific population centers.

Facebook and revealed their intentions last week to connect the developing world through aerial drones and satellites. Their plans drew the inevitable comparisons to Google’s Project Loon, which would field fleets of balloons in the Earth’s stratosphere. The similarities weren’t lost on Facebook founder and CEO Mark Zuckerberg.



Zuckerberg published a treatise Friday detailing many aspects of’s new connectivity projects, and while he didn’t mention Google or Project Loon by name, he did make a point of explaining why he feels drone technologies are superior to balloons when it comes to delivering internet access to the world’s unconnected.

Since the drones are essentially unmanned planes, will be able to precisely control their location and movements, Zuckerberg wrote. That means they will be able to circle their coverage zones in tight circles, move easily to other coverage zones or fly themselves to a maintenance facility for repairs.

Project Loon balloons will basically be floating on the atmospheric winds. They’ll be able to steer themselves in part by adjusting their altitude, catching atmospheric cross-currents to change direction. But they certainly won’t have the controlled precision of winged aircraft.

Zuckerberg further wrote that the goal of any aerial broadband system should be to find that sweet spot in altitude that will allow them to fly higher than regulated airspace and the troposphere’s weather patterns, while still being close enough to the Earth’s surface to send out a strong broadband signal to the ground.

Both Loon and’s drones would fly at the same altitude — about 12 miles up — but aircraft are better suited to dealing with the rigors of that height, Zuckerberg said. Loon balloons are being designed to stay aloft for 100 days – or three trips around the world. Zuckerberg said might be able to extend some drones’ flights for years.
From the paper:

“Based on these constraints, drones operating at 65,000 feet are ideal. At this altitude, a drone can broadcast a powerful signal that covers a city-sized area of territory with a medium population density. This is also close to the lowest altitude for unregulated airspace, and a layer in the atmosphere that has very stable weather conditions and low wind speeds. This means an aircraft can easily cruise and conserve power, while generating power through its solar panels during the day to store in its batteries for overnight use.

“With the efficiency and endurance of high altitude drones, it’s even possible that aircraft could remain aloft for months or years. This means drones have more endurance than balloons, while also being able to have their location precisely controlled. And unlike satellites, drones won’t burn up in the atmosphere when their mission is complete. Instead, they can be easily returned to Earth for maintenance and redeployment.”

Zuckerberg makes plenty of good points, but he does seem to be sidestepping the point that Google isn’t necessarily looking for precision and control in its aerial network. The goal of Loon is to quite literally blanket the stratosphere with internet radios, letting them float freely on east-west winds. Google needs control of these balloons only in the sense that it needs to keep them spaced evenly apart so they can provide consistent coverage and capacity as they pass overhead.

project loon balloon

In contrast, wants to build a much more rigid network, with drones hovering over pre-defined population areas. That approach is probably a lot more efficient — Google Balloons will spend a lot of time beaming their signals into open ocean — but by definition that approach demands have much more control over its aircraft.

Zuckerberg’s connectivity treatise had several more interesting nuggets. In the paper, Zuckerberg readily admitted that many of the technologies is exploring are still in the experimental phase. For instance free-space optics technologies have been around for a while, but the type of free-space optics Facebook is talking about – pointing a laser mounted on fast-moving object at another fast-moving object – still needs plenty more research.

As for rural coverage, also hasn’t settled on whether it will use geostationary satellites, which hover at fixed points relative to earth at far-distant orbits, or low-earth orbit satellite constellations, which whiz over our heads at a rapid pace. In the paper, Zuckerberg discussed the merits and drawbacks of both approaches.

earth outline

And what’s particular intriguing is Zuckerberg broached the idea that Facebook and might be looking beyond suburban and rural connectivity to connecting major population centers where the telecom carriers have focused their efforts.

“… in urban environments, wireless mesh networks can provide simple to deploy and cost effective solutions,” Zuckerberg wrote. “We will discuss this further in a later paper.”

Via Gigaom