After two years of development, on June 28th Facebook completed the first successful flight of Aquila. If you’re not familiar with the project, Aqila is Zuckerberg’s massive solar-powered plane that will deliver internet to remote parts of the world.
Yuma, Arizona played host to the historic occasion, and while the original flight plan was for just 30 minutes, things went so well, they kept the plane up for more than 3 times that, for a total 96 minutes.
As you can imagine with anything launched in 2016, there was a staggering amount of data collected from on-board sensors, that captured information about the real-world performance of the aircraft, which will allow them to contrast with computer simulations.
The long-term goal is to have a fleet of Aquilas flying together at 60,000 feet, connected and communicating with each other with lasers, yep, freaking laser beams and staying aloft for months at a time. If achieves this, it’ll set the record for the longest unmanned flight.
Flying is hard at the best of times, but there’s some pretty unique challenges with this project. This morning Zuckerberg detailed some of the most difficult engineering challenges. The unmanned drone is wider than a Boeing 737, yet weighs only one third of an electric car while only using the equivalent of 3 hairdryers.
Aquila has a wingspan wider than a Boeing 737, but has to weigh as little as possible to stay up for as long as possible. That’s why the body of the plane is made of a carbon fiber composite so the whole thing weighs less than 1,000 pounds — or about the same as a grand piano. We need to continue to make it lighter.
The amount of energy Aquila collects from the sun during the day has to be enough to keep its propellers, communications payload, avionics, heaters and light systems running when it’s dark. That means using about 5,000W of power at cruising altitude, or about as much as three hairdryers. We’re always looking for ways to trim this down and make our systems more efficient.
Aquila is mostly self-sufficient, but it still relies on a ground crew of about a dozen engineers, pilots and technicians who direct, maintain and monitor the aircraft. They control the aircraft through software which allows them to determine heading, altitude and airspeed — or send Aquila on a GPS-based route. Takeoff and landing are automatic, since no human pilot can land in a precise location as well as software can.
When you see Aquila fly, one of the most surprising things is how slow it goes. That’s on purpose. In order to use the least amount of energy, Aquila needs to go as slow as possible. At higher altitudes, where the air is thinner, we’ll be able to go a bit faster — about 80 mph.
In order to take off, fly and land, Aquila’s wings and propellers have to be able to operate both in high, cold altitudes and lower, warmer altitudes where the air can be 10 times denser. We’re working to figure out how much power that takes — and what impact it will have on solar panel performance, battery size, latitude range and seasonal performance.
Almost half the mass of Aquila will come from high-energy batteries. That’s a lot of weight to put on large, flexible wings, which is why we have computer models to predict how Aquila’s shape deforms under load. A few more flights will help us better understand the actual in-flight dynamics.
Communications — Aquila will carry a communications payload that will use lasers to transfer data more than 10 times faster than existing systems. It will be able to aim its beams precisely enough to hit a dime more than 11 miles away while in motion.
For more information at Facebook.