The flight took place before dawn in Arizona on June 28th. The original goal was to fly Aquila for 30 minutes, but things went so well that it was decided to keep the plane up for 96 minutes. During which, the Aquila’s team gathered lots of data about its models and the aircraft structure.
Zuckerberg, who was present at the test, said on Facebook: “After two years of development, it was emotional to see Aquila actually get off the ground.
“But as big as this milestone is, we still have a lot of work to do. Eventually, our goal is to have a fleet of Aquilas flying together at 60,000 feet, communicating with each other with lasers and staying aloft for months at a time - something that's never been done before,” he added.
The carbon fibre Aquila has a wingspan of 141ft - wider than a Boeing 737, but weighs just 453kg, around half of this mass is taken up by its batteries. The drone has to weigh as little as possible to stay up for as long as possible, and Facebook aims to continue making 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. In order to use the least amount of energy, Aquila will travel at a maximum of 80mph at its highest altitude, where the air is thinner
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 it on a GPS-based route.
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. The team is working on much power that would take, and what impact it will have on solar panel performance, battery size, latitude range and seasonal performance.
Aquila will carry a communications payload that will use lasers to transfer data more than 10 times faster than existing systems, Facebook claims. It also says that “it will be able to aim its beams precisely enough to hit a dime more than 11 miles away while in motion”.
There are many challenges to overcome before a fleet of Aquilas are launched for 90-day stretches. Some of which include: creating batteries with sufficient density for sustained flight; bringing the costs down to an affordable level; and working out how the lightweight drone will react when solar panels are added, as the one being tested used only batteries for its 96-minute flight.
The drone is more than a proof-of-concept, to Zuckerberg it’s a tool to pass on the educational and economic benefits that the internet affords to remote areas of the world.
Zuckerberg said: “Over the next year we're going to keep testing Aquila - flying higher and longer, and adding more planes and payloads. It's all part of our mission to connect the world and help more of the 4billion people who are not online access all the opportunities of the internet.”
Facebook isn’t the only company trying to bring the internet to the whole world. Global communications company, OnWeb recently announced the opening of a facility where it will volume manufacture a 648 strong network of cubesats that it says will form a network able to beam affordable internet to any location on the planet. Also, Google is testing Project Loon, where balloons measuring 12 x 15m carry what is essentially a cubesat to 20km above the Earth to form a network, beaming internet signals back down to remote locations.
