Alphabet’s Loon balloons have flown for 1 million hours

Loon is Alphabet’s moonshot for providing worldwide internet access via high-flying balloons. The independent company today announced that its vehicles have flown over 1 million hours in the Earth’s stratosphere.

Google began testing the balloon-powered internet concept in 2011. Since then, Loon’s balloons have flown nearly 40 million kilometers, or 1,000 times around the Earth. The data garnered over those trips have created what the Loon team considers an “atmospheric Rosetta Stone.”

The prior information gathered over our 40 million kilometers of flight is the equivalent of an atmospheric Rosetta Stone that shows us how to fuse together these two sources of data [wind forecasts from global numerical weather models and real-time measurements] and make educated guesses about what movements the balloons should make.

Algorithms are responsible for adjusting not only the flight path, but also the altitude. This complex automation is handled largely by software given the “minute-by-minute attention needed.” The end goal is to “maximize the navigational efficiency of the Loon fleet.”

While we have a dedicated team of flight engineers that monitor every balloon 24/7/365, it is this system, not humans, that directs the movements of Loon’s balloons. It makes the decisions necessary to get a balloon around the world and keep it above a desired location for months at a time.

Loon today shared some interesting insights, with the system developing “clever and complex navigational behaviors” that were not programmed by human engineers.

• Tacking: “… we notice the balloons sometimes fly a zig-zag pattern in which they stray from their course, in some cases almost reversing themselves, before resuming in the desired direction.”
• Loitering: “The new winds would allow the balloons to simply drift straight back toward Puerto Rico, rather than taking the longer, circular route through South America. The algorithm guessed it would be quicker to wait. And it was right: The winds changed and the balloons returned to Puerto Rico in less time.”
• Figure 8s: “The very first time we tested our ability to stay in one place using our new automated algorithm, the balloon immediately began flying an unexpected pattern. Rather than circle the area, the balloon flew in a figure 8 pattern. And not just once, it did it all day.”